NEWS.md

In rcicr: Reverse-Correlation Image-Classification Toolbox

rcicr 1.5.0 (2026-09-25)

Reproducibility impact

• batchGenerateCI() and batchGenerateCI2IFC() now group a tibble correctly. Called on a tibble with more than one group in by, rcicr 1.1.0 through 1.4.1 returned a single classification image instead of one per group. That image was built from alternating trials of different groups and named after the first group. A data.frame, or a tibble with one group, was never affected, and its results do not change. (#336)

You were affected if the list these functions returned had one element although your data held several participants or conditions; data read with readr or processed with dplyr is a tibble. Recompute those CIs with this version, or with an older one after as.data.frame(). No stimuli need regenerating or responses recollecting. Of the affected versions, only 1.3.0 and 1.4.1 were released on CRAN; the others were GitHub releases. The 1.1.0 entry below saying these functions accept tibble columns held only for a single group.

• The default InfoVal reference now needs the stimulus seed saved in the file. Without a response_seed, the reference replays that seed. A file without one (made with generateStimuli2IFC(seed = NULL), or with the seed field removed) now stops with an error before anything is simulated. The error gives the call that stores a reproducible reference, generateReferenceDistribution2IFC(rdata, response_seed = <n>), which later computeInfoVal2IFC() calls reuse, and, for a file that cannot be written, computeInfoVal2IFC(..., response_seed = <n>). Files with a seed are unaffected.

Such a file used to reseed from the clock, so its reference could not be reproduced. generateReferenceDistribution2IFC() and computeInfoVal2IFC(force_gen_ref_dist = TRUE) returned a different one on every call. The first automatic computeInfoVal2IFC() stored one that later calls reused, so the InfoVal was stable on that copy of the file and different on any other. This happened on every version back to 1.0.1 for files made with seed = NULL, and on 1.4.0 and 1.4.1 for files without the field; earlier versions stopped on those. A reference already stored by 1.4.0 or later is still used, with a message that it cannot be regenerated from the file. An older stored reference, which rcicr rebuilds, now stops like any other. Replacing either with a seeded reference makes the InfoVal reproducible; it will differ from the one reported before. (#334)

Bug fixes

• Saving a reference distribution no longer risks the stimulus .Rdata file. computeInfoVal2IFC() and generateReferenceDistribution2IFC() store the reference in that file, and a save that was interrupted (Esc, an error, R killed or crashing) could leave it unloadable, losing the only record of the stimuli. The file is now backed up beside itself for the duration of the save, as <file>.rcicr-backup, and restored automatically if the save fails. It keeps its owner, group and permissions. (#333)

If R is killed during the save, the backup remains, and any function that reads the damaged file says so. If the file still loads, the next save stops and asks you to delete the backup, since rcicr does not delete a file it cannot prove it made. If the file no longer loads, check that the backup holds this experiment (the error shows how), restore it with file.copy("<file>.rcicr-backup", "<file>", overwrite = TRUE, copy.mode = FALSE), check that the file loads again, and only then delete the backup. Leftover <file>.rcicr-staging-* files are incomplete copies and can be deleted.

Limits: a writable file in a read-only directory (Unix), and a file name over 228 bytes, are saved as before, without a backup, with a warning. On Windows, a writable file in a folder that refuses new files now stops with an error instead of being saved, as does any save where the backup cannot be made, such as on a full disk. On Windows the backup has its folder's permissions rather than being private to you. Power loss and operating-system crashes are not covered, and two R sessions saving the same file at once remain unsafe.

• generateCI() stops when some, but not all, participants IDs are NA. It used to return a CI in which every pixel was NA, with only min/max warnings, and write it as a solid black PNG; every version since 1.0.1 did this. The error names the trials without an ID. Give them one, or remove them from stimuli, responses and participants alike. An all-NA participants still means no grouping, and no valid result changes. (#337)

• generateStimuli2IFC() never overwrites a stimulus .Rdata file. Its file name records the minute, so two calls into one folder with the same label and seed in the same minute used to write one file, and the first set's PNGs lost the only record of their noise parameters. The name is now reserved before anything is generated, and the call stops, having written nothing, if that file exists or if another call into the same folder with the same seed, started in the same minute, is still running. The error says to use a different label or stimulus_path, or to delete the file if the set is being regenerated on purpose. The time in the name is now the start of the call rather than its end. (#338)

• An img_size the noise scales cannot tile now gets an error that says so. The finest of nscales scales tiles the image with 2^(nscales - 1) patches per side, so img_size must be divisible by that. generateNoisePattern(), and through it generateStimuli2IFC() and simulateNoiseIntensities(), used to fail with "number of items to replace is not a multiple of replacement length". The error now names the constraint, the nearest valid sizes and the largest nscales that fits. Every size that worked still works. (#339)

Documentation

• Corrected help pages that disagreed with the code:
• generateStimuli2IFC(return_as_dataframe = TRUE) returns one row per pixel and one column per trial, not the reverse.
• generateCI() takes its scaling constant as scaling_constant, not constant.
• batchGenerateCI() also accepts scaling = "matched".
• plotZmap() takes a background image matrix, not an .Rdata file.
• generateNoisePattern() returns four elements, not two.
• ?computeInfoVal2IFC cites the published InfoVal paper (Brinkman et al., 2019) instead of a manuscript in preparation.
• computeInfoVal2IFC() always simulates a reference distribution the .Rdata file does not hold; rcicr ships no precomputed ones.
• Rewrote the README, both vignettes and the help pages for readability. The "no longer actively maintained" notice is removed from the README.

rcicr 1.4.1 (2026-09-15)

Documentation

• Removed the obsolete Medium tutorial link; the maintained package vignette is the current walkthrough.

rcicr 1.4.0 (2026-09-13)

Reproducibility impact

• InfoVal references for independent base images now use the selected base's saved noise. Previously, with multiple bases and use_same_parameters = FALSE, bases after the first were scored against the first base's reference. Shared-parameter results and the default simulated-response stream are unchanged. This defect did not affect classification images, z-maps, stimuli or responses.

The first base's InfoVal is also unchanged for files written from rcicr 0.3.0 onward. For older independent-base files, even the first base can change: their stored noise cannot be reconstructed by the newer generator from the seed alone. Recompute InfoVal for all bases in those files.

When saved parameter matrices differ, both computeInfoVal2IFC() and generateReferenceDistribution2IFC() now require the baseimage label used for generateCI(); omitting it reports an error. References are cached separately by base, preserving but ignoring old unscoped norms. Recompute affected InfoVal values from the existing CI object and stimulus .Rdata, using the same base label (here, "second"):

r computeInfoVal2IFC(ci, "rcic_..._.Rdata", baseimage = "second")

No stimuli need regenerating or responses recollecting. The synthetic analysis in #307 characterizes the reference mismatch through modeled shifts across 100 base-image pairs. It does not estimate affected-study rates or bound an individual study's change; recomputing its InfoVal gives that change.

• InfoVal references now use the saved noise basis and parameters. Scoring no longer reopens base images or reconstructs the stimuli from their seed. Archived experiments with moved images and uniform bases made with maximize_baseimage_contrast = FALSE can therefore be scored. The obsolete nscales, noise_type and sigma fallback warnings are removed. (#301)

References can change for pre-1.1.0 files whose missing settings were previously replaced by defaults, and for pre-0.3.0 files whose parameters could not be reconstructed from the seed. References are otherwise reproduced bit-for-bit when the old reconstruction matched the saved noise and the same RNGkind() is used for the response draws. Changing the RNG kind changes those draws, not the saved noise basis. The CI itself is unaffected; no stimuli need regenerating or responses recollecting.

Existing default caches without matching provenance are refreshed once, for both shared and independent bases. Automatic refresh keeps the cached iteration count and preserves the caller's random state. Explicit regeneration still uses the requested count and advances the random stream. Read-only files use the norms in memory and identify the file and, for independent references, the base that could not be saved; they build them again on the next call. That applies to every reference computeInfoVal2IFC() builds, not only a refresh — see Bug fixes.

If the norms change, a message says that the returned InfoVal supersedes earlier values. This is a message under every warning setting, including options(warn = 2); it is not collected by warnings() and can be hidden by suppressMessages(). Unchanged norms produce no superseding notice. Provenance includes a full copy of the norms, compared exactly, so an older writer cannot leave a trusted marker on replaced values. Earlier development fingerprints refresh once; no new package dependency is needed.

Deliberately seeded caches are retained. Explicitly regenerate any seeded reference built from an incorrect reconstruction, including affected pre-1.1.0 files, before recomputing InfoVal.

• generateStimuli2IFC() now ignores an image's alpha channel when reading a base face. Greyscale and RGB images are unaffected. At the default contrast setting, an opaque PNG can differ only in rounding in the stored base-face doubles; its participant-facing 8-bit stimuli and rendered CI are unchanged. A base with varying transparency, or any alpha image with contrast maximization disabled, could previously look visibly distorted in the stored base, stimuli and rendered CI. The CI calculation remains correct for the stimuli shown. If a base needs correcting, inspect and flatten or composite the source image as intended, regenerate the stimuli and collect new responses; do not rerun generateCI() from the existing .Rdata.

• Malformed CI trial inputs now report an error instead of silently changing trial assignments. generateCI() requires one participant ID per trial when grouping is enabled. It, generateCI2IFC() and computeCumulativeCICorrelation() reject empty, missing, nonfinite, nonpositive, fractional or out-of-range stimulus IDs, and factor, character or logical IDs. Direct generateCINoise() calls reject mismatched parameter rows and responses. Valid numeric inputs and the all-NA no-grouping convention are preserved. If an existing script now errors, recover the correct trial IDs and participant assignments from the experiment records and recompute affected CIs and downstream results; do not pad or recycle IDs to satisfy the check. (#294, #300)

• A classification image with no range now renders as a uniform neutral image instead of NaN. Three cases divided by a zero range. generateCI() under its default scaling = "independent" did so for a CI whose pixels are all exactly zero — what exactly cancelling responses produce — making every pixel of $scaled and $combined NaN. Under scaling = "matched" the same happened for any CI with no variation at all, a uniform non-zero one included. autoscale() did so when every CI in its list was zero, in $scaled only: it leaves the caller's $combined untouched, as always.

All three now fill the unmasked pixels with a neutral value and warn: 0.5 for independent and autoscale(), which is what constant scaling already returned for the same input, and the midpoint of the base image's range for matched, which renders into that range. Masked pixels keep their NA and the unscaled $ci is unchanged.

Every value that changes was NaN before. No finite number moves, no CI with any variation in it is affected, and a result that was NaN cannot have carried a published number. (#303)

Behaviour changes

• generateStimuli2IFC() now writes stimuli for every base image when it also returns a data frame. With more than one base image and return_as_dataframe = TRUE, only the first base image's PNGs were written, although the call succeeded and the .Rdata file recorded every base image's parameters. A stimulus set generated that way is incomplete: re-run the same call with the same seed to write the missing files. Nothing already collected is invalidated. The stimuli that were written are unchanged, as is the returned data frame, which still holds one noise image per trial for the first base image. (#302)

Bug fixes

• Parallel workers now start whatever the session's OutDec and scipen are. With both options(OutDec = ",") and a scipen negative enough to force scientific notation — neither alone does it — every call that spawns workers failed, after waiting out the whole connection timeout and then naming the workers rather than the cause: generateStimuli2IFC(), generateCI() and friends with n_cores > 1, and reference generation. parallel renders a worker's port into a command line as text, where those options wrote 11000 as 1,1e+04 for the child to read as NA. Both are now neutralised across cluster construction and restored immediately afterwards. They govern rendering and never arithmetic, so no numeric output changes and no existing result is affected. (#316)

• Scoring a read-only archive no longer fails when it has no cached reference to reuse. computeInfoVal2IFC() simulates the reference before storing it, then asked to store it even where the file could not be written, so a call that had already computed its answer ended in cannot open the connection. Three cases reached it: a stimulus file with no cached reference, force_gen_ref_dist = TRUE, and — for saved base images with different noise parameters — any archive predating per-base caches, whose unscoped reference_norms older versions of rcicr scored from without writing anything. Only an unsolicited refresh of a stale cache had the fallback. All of them now use the computed norms in memory, say which file and base could not be saved, and leave the archive untouched. The InfoVal is the value a writable run returns; nothing about how references are simulated or cached changed. A direct generateReferenceDistribution2IFC(save_rdata = TRUE) still reports an error, because there the save is what was asked for.

Performance

• generateReferenceDistribution2IFC() no longer re-copies its stimulus data on every simulated response set (#306). Converting it once per call speeds up reference simulation, and so the computeInfoVal2IFC() calls that have to generate one. The gain is largest at small image sizes and narrows as the matrix-vector product itself becomes memory-bound. Reference norms and the random-number stream are unchanged.

Documentation

• ChangeLog is frozen at 1.0.1 and is no longer updated. It keeps the record of everything before 1.1.0, including the whole CRAN era up to the archived 0.3.4.1. NEWS.md is the changelog from 1.1.0 onward and the only one R indexes, so news(package = "rcicr") is unaffected. Entries for 1.1.0 to 1.3.0, which only pointed here, were removed from it.

rcicr 1.3.0 (2026-08-18)

Behaviour changes

• A decorated z-map on a device too small for it now says so, and can be made to fit. plotZmap(decoration = TRUE) needs room for margins, labels and the colour scale — about 160px at the default text size on Linux and macOS, and about 200px on Windows, whose graphics device is 96 ppi where theirs is 72 — and below that base R stopped with figure margins too large, naming neither rcicr nor a way forward. It now stops with a message giving the size, the minimum, and the three ways out. plotZmap() gains pointsize and generateCI() gains zmappointsize: the decoration is measured in lines of text, so a smaller size fits it onto a smaller image. This matters most through generateCI(), which sizes the z-map to img_size, so a stimulus set below about 160px could not produce a decorated z-map at all — a 128px set now can, with zmappointsize = 6.

Both arguments default to the graphics device's own 12, so every existing call renders exactly as before; a 512px decorated z-map is byte-identical.

• plotZmap() no longer depends on raster, and its ... arguments now go to graphics::image() instead of the raster package's plot method. col behaves the same way in both (and now actually works — see the bug fixes below); a call passing an argument specific to that method will now be rejected as unused. Dropping the dependency also removes terra, sp and Rcpp, and with them the GDAL/GEOS/PROJ system libraries that every Linux CI job had to install before it could start.

The z-map itself renders identically — the undecorated figures generateCI() writes are pixel-for-pixel the same as before, within colour quantisation, and a golden reference rendered by the old raster code is committed as a test fixture to keep it that way. The palettes are unchanged, including the quirk that a z-map drawn over a background image uses the default palette rather than the viridis one.

• A decoration = TRUE z-map is laid out slightly differently. The colour bar is now drawn by hand rather than by raster, and the map is a few pixels wider at 512px. If you regenerate a decorated z-map figure, it will not be pixel-identical to one saved with 1.2.3 — the same is already true of regenerating it on a different operating system, and for the same reason: what a graphics device paints is not part of what this package computes. No z-score, classification image, scaling result or informational value changes, and generateCI()'s own z-map figures are undecorated and unaffected. See ?plotZmap, "Reproducibility across platforms".

• generateCI(mask = matrix(NA, 1, 1)) now reports the malformed mask instead of silently ignoring it. The internal test for "was a mask supplied?" asked only whether the argument was a single NA — which a one-cell NA matrix, a one-element array(NA) and a list(NA) all are. Such a mask was mistaken for the NA default, discarded without a word, and an entirely unmasked classification image came back. A call that passes a mask and gets an unmasked CI is the failure worth catching early; it now stops in the same mask validation every other malformed mask reaches. The sentinel is now specifically an atomic scalar with no dimensions, so mask = NA still means "no mask" — it is the default, and every unmasked call relies on it — while matrix(1, 1, 1), larger matrices, PNG paths and NULL are unchanged.

• generateStimuli2IFC() now checks base_face_files before it generates anything, and names the entry it cannot use. Four inputs used to get past the old check and fail from inside a parallel worker with attempt to select less than one element in get1index, which names neither the argument nor the file: a list with no names, a list with some names missing, an empty list, and an element that is not a single file name. They now stop immediately with a message saying which entry is wrong and why.

One of them could previously appear to work. A base_face_files with two entries under the same name silently dropped all but the first — the loop looked each name up by string, so list(face = 'a.png', face = 'b.png') produced one set of stimuli, from a.png, and nothing at all from b.png. That is now an error naming the duplicated name. If you have a script that relies on it, the stimuli it produced were never what the call asked for; give each base image its own name.

• The PNG-or-JPEG test now looks at the file extension rather than anywhere in the path. It was grepl('png|PNG', filename) against the whole path, so a JPEG stored under a directory called png was handed to png::readPNG() and died with file is not in PNG format, blaming the file for a choice the package had made. Files are now recognised by a .png, .jpg or .jpeg extension, case-insensitively. A base image whose extension does not say what it is is rejected up front, by name, instead of reaching a reader that cannot parse it.

• The .Rdata validation errors now name the version of rcicr that wrote the file. generateCI() and computeCumulativeCICorrelation() already said which field a file was missing; they now also say where the file came from, which is what turns "this file has no stimuli_params" into "it predates the version that added it — regenerate the stimuli, or install that version". The version is read tolerantly, because the field cannot be taken at face value: p$generator_version is preferred over the top-level generator_version, which every release from 0.4.0 through 1.1.0 recorded as a hardcoded 0.4.0, and a file that only claims 0.4.0 is reported as unknown rather than as 0.4.0. A file with no version field at all reports the absence and stops there — an absent field is equally a file older than 0.4.0, a truncated one, or one rcicr never wrote.

generateReferenceDistribution2IFC()'s two warnings about a missing nscales or noise_type were reworded for the same reason. They said the file "was written by a version of rcicr that did not save" the field, which an absence does not establish; they now report what is missing, and keep the version as context rather than as a conclusion. The advice is unchanged, and was always right either way: regenerate the stimulus set with this version.

• A stimulus file with gabor noise and no saved sigma now says so. generateReferenceDistribution2IFC() assumes the historical default of 25 when a file predates 1.1.0 and lacks the field, which it has always done silently — unlike the loud warnings for a missing nscales or noise_type. For gabor noise that silence hid the same hazard those warnings exist for: sigma is what shapes the Gaussian mask, so guessing it wrong rebuilds the null on a different noise basis than participants saw, and the resulting InfoVal is wrong. On a 1.0.1 gabor stimulus set the reference norms move from 0.681/0.689/0.680 at sigma = 25 to 0.615/0.620/0.626 at sigma = 10.

Sinusoidal files are unaffected and stay silent, which is the point of doing this by noise type rather than by field: sigma reaches the basis through generateGabor() alone, so for sinusoidal noise the norms are identical whatever it is, and a warning would be pure noise on the far more common legacy file. Nothing warns that did not previously produce a wrong answer, and no numeric output changes.

• plotZmap(mask = ...) now accepts a mask with an alpha channel. It previously required every colour channel of a multi-channel PNG mask to match exactly, so a greyscale-plus-alpha or RGBA mask whose alpha plane happened to differ from its colour planes was rejected — alpha carries no colour information and is now always ignored, matching generateCI(mask = ...). A rectangular zmap/mask pair continues to work as before. plotZmap(mask = ...) also now rejects a mask that is neither a string nor a matrix with a clear error, instead of failing later inside png::readPNG() with an unrelated message.

• plotZmap(mask = NA) now means "no mask", as it already does in generateCI(). The two functions detected a supplied mask differently — plotZmap() asked only whether the argument was non-NULL — so the same sentinel meant opposite things: generateCI() read NA as "no mask" while plotZmap() passed it on and stopped with The mask argument is neither a string nor a matrix!. NaN behaved the same way. Both now render an unmasked z-map. No call that worked before changes: the inputs affected all raised that error.

• generateStimuli2IFC() no longer saves trial in the .Rdata file. It was the loop counter left over from stimulus generation — always equal to n_trials, which is already saved. Nothing in the package or the documented contract reads it. Existing .Rdata files that contain trial continue to work; the field is simply ignored on load.

Reproducibility impact

• Individual-CI PNGs written by generateCI(save_individual_cis = TRUE) carried the wrong participant's name, and are now named correctly. The per-participant loop selects each participant's trials by sorted order and took the output filename from order of appearance. At each position where those two orders differ, the file in <targetpath>/individual_cis was given another participant's ID. The pixels were always right; only the names were wrong.

Affected: a direct call to generateCI(participants = ..., save_individual_cis = TRUE) where the participants vector is not already in sorted order. Such a call produced correct images under incorrect filenames, so a figure published as participant p2 may be someone else's classification image.

Do not assume tidy data was safe — the common case is affected. Sorting is lexical, so text labels like "p10" sort before "p2". A study whose participants appear in collection order p1, p2, ..., p10 is therefore affected from the tenth participant onward, even though nothing about that data is out of order in any ordinary sense:

| participants, in collection order | affected | |---|---| | "p1" … "p9" | no | | "p1" … "p10" or beyond | yes | | "p01" … "p12" (zero-padded) | no | | "1" … "12" (character) | yes | | 1 … 12 (numeric) | no |

Unpadded text IDs and ten or more participants is the ordinary shape of a reverse correlation study, so if that describes yours and you used the call above, check rather than assume.

Not affected — and this is the documented route, so most analyses are in this group:

• batchGenerateCI(), batchGenerateCI2IFC() and generateCI2IFC(). None of them exposes participants or save_individual_cis at all; they split the data themselves and name each image from the grouping value directly, never reaching the code that was wrong. Per-participant classification images computed the way the package documentation has recommended since the CRAN era — batchGenerateCI2IFC(), and batchGenerateCI() in the current vignette — were correctly labelled throughout.
• Everything generateCI() returns. The group classification image is a mean across participants and so does not depend on their order; the per-participant stack, and every z-map built from it, were internally consistent throughout. No returned value, and no number in any .Rdata file, ever changed.
• Any call that left save_individual_cis at its default FALSE. No individual-CI file was written, so there was nothing to mislabel.
• Participants already in sorted order, where the two orderings coincide.
• Every CRAN release. rcicr was on CRAN from July 2014 until it was archived in June 2021; the last release, 0.3.4.1 (July 2016), predates the save_individual_cis option entirely. install.packages('rcicr') never produced a mislabelled file at any point.

If you have published from individual-CI images, check your analysis scripts. Two steps, neither of which requires re-running anything. The individual-CI filename advisory carries the fuller version of this, including what the mislabelling does to a second-stage analysis and how much of an effect survives it; where the two differ, that page is kept current and this section is not.

Step 1 — did you use the relevant call at all? Look for an individual_cis/ directory in your output. Nothing else in the package creates it, so finding it means the direct call ran. For output made before 1.3.0, continue to step 2. If your per-participant images came from batchGenerateCI() or batchGenerateCI2IFC(), those cannot reach the defect.

Check the output rather than the script. save_individual_cis is the sixth formal of generateCI(), so a call can set it positionally — generateCI(stim, resp, "face", rdata, pids, TRUE, ...) — and write those files without the argument name appearing anywhere; do.call() hides it the same way. Searching your scripts and finding nothing does not clear an analysis.

Not finding the directory clears it only if the output still sits where the run left it. Renamed, archived or moved, it will not answer to that name, and the individual files are then recognisable but not conclusive: ci_<participant>.png is what the affected call writes, and also what generateCI(save_as_png = TRUE, filename = "<participant>") writes for a group CI one directory up.

Step 2 — if the directory is there, was your participants vector in sorted order? Note "sorted" means lexically sorted for text labels, per the table above — sorting your data frame by a "p1"-style column does not make it safe once you reach ten participants. Where you still have the vector, one expression settles it:

r identical(unique(participants), sort(unique(participants))) # TRUE = names were correct

Two conditions on that TRUE, both of which change what sort() returns: use the original participants object rather than a character copy, since a factor carries its own level order and sort() follows it; and run it under the collation the original analysis ran under, since identifiers mixing case, accents or punctuation sort differently by locale. Numeric identifiers are not exposed to the second, numeric sorting being locale-independent, and p1/p12 are not realistically exposed either. Lowercase ASCII is no guarantee in general, though, since some locales collate letter pairs as units (Czech ch, Danish aa).

If the output is long gone and only the script survives, search it for individual rather than the full argument name, and read by hand any generateCI() call passing six or more arguments positionally.

Recovering existing output is a rename, not a re-run. The mapping is exact: the file named unique(participants)[i] holds the classification image of sort(unique(participants))[i].

r old <- unique(participants) # the names the files were given new <- sort(unique(participants)) # the participants they actually hold

Every release from 1.0.1 (January 2023) through 1.2.3 (August 2026) carries the defect, as does every install from the development branch from 15 August 2017 onward — the date it was introduced, in the commit that first made individual-CI saving work at all. There were no releases between 2017 and 2023, so a copy obtained in those years came from the branch and is affected too.

Getting it from GitHub took a deliberate step, until December 2021. The default branch was master, which carried an older repository layout with no DESCRIPTION at its root, so install_github('rdotsch/rcicr') did not install anything at all — it failed. The affected code was on the development branch, reached only by asking for it: install_github('rdotsch/rcicr', ref = 'development'), which the README of the time labelled "AT YOUR OWN RISK" and specifically advised against for analyses meant for publication. development became the default branch on 2021-12-28, and from then a plain install returns affected code.

If you need to work out which version a stored analysis actually used, the version number alone will not tell you: 0.4.0 sat on the development branch for five years, with the defect entering partway through. A note listing every release, its date, whether it came from CRAN or GitHub, and what "the latest version" gave you in each window is at https://github.com/rdotsch/rcicr/blob/main/notes/individual-ci-mislabelling.md.

• computeCumulativeCICorrelation() with a masked targetci now returns numeric correlations where it previously returned all-NA. No existing analysis could have used the old result — it carried no information — but code that checked for NA on the returned curve will see a different answer. Unmasked targets are bit-identical.

Bug fixes

• generateCI(save_individual_cis = TRUE) names each PNG for the participant it was actually computed from. The loop selects participants by sorted level order and the filename was taken from order of appearance, so the two disagreed for any data not already sorted by participant. See "Reproducibility impact" above for how to tell whether files you already have are affected, and how to correct them without recomputing anything.

• computeCumulativeCICorrelation() now returns real correlations when targetci was generated with a mask. generateCI() stores NA in every pixel a mask excludes, and the correlation was taken over all pixels (use = "everything"), so a single masked pixel made every point on the curve NA however strong the signal. Correlations are now computed over the unmasked pixels only. A fully masked target (every pixel NA) still returns an all-NA curve — there are no complete pairs to correlate.

• plotZmap(col = ...) works. Supplying a palette is how ?plotZmap has always told you to change the colours, and doing it stopped the call with formal argument "col" matched by multiple actual arguments before anything was drawn — the function passed its own col alongside yours. This affected every released version; the argument is now taken as an override, and is used for the colour bar as well as the map.

• A base image with no contrast no longer becomes an all-NaN base image. Under maximize_baseimage_contrast = TRUE, the default, generateStimuli2IFC() rescales with (img - min(img)) / (max(img) - min(img)) — which is 0/0 when every pixel is the same value. The resulting NaN base face was written into the .Rdata with no error and no warning, every classification image computed from that stimulus set inherited it, and the stimuli themselves came out uniformly black, png::writePNG() clamping NaN to zero. It now stops with an error naming the file.

A photograph is never uniform, so this bit synthetic and accidentally-blank base images — but it failed silently, and the symptom appeared a long way from the cause. The error fires only under maximize_baseimage_contrast = TRUE: a flat base image is perfectly usable with the rescale switched off, and the message says so.

• computeCumulativeCICorrelation() reads pre-0.3.0 stimulus files again. Files written before rcicr 0.3.0 (January 2015) store 4096 contrast parameters per trial where only 4092 patches exist, and generateCI() has truncated the four unused columns for years. computeCumulativeCICorrelation() did not, so on such a file the extra columns reached generateNoiseImage() as a length mismatch and it aborted with "number of parameters doesn't equal number of patches" — the cumulative-correlation curve could not be computed at all. It now applies the same truncation. Files from 0.3.0 onward already have 4092 parameters and are unaffected. The same fix keeps a single presented stimulus two-dimensional, so a one-stimulus call — which aborted with "incorrect number of dimensions" on any file — now returns its (single-point) curve.

• generateCI() with participants works again on more than one core. Supplying participants without targetpath — the normal thing to do when you are not saving individual CIs — stopped with argument "targetpath" is missing, with no default as soon as n_cores was greater than 1, which is the default on any multi-core machine. foreach inspects the loop body and fetches every variable it mentions, including one used only in the branch that saves individual CIs, and that branch is precisely the one that cannot run when you have not asked for those files. Single-core calls were unaffected, as was saving individual CIs with a targetpath.

• The progress bar moves again during parallel runs. generateStimuli2IFC() and generateCI() build their progress bar in your session but were advancing it from inside the parallel loop, where each worker holds a private copy — so under the default (ncores/n_cores greater than 1) the bar sat at 0% for the whole job and jumped to 100% at the end. On a 770-trial 512px set that is a long time with nothing to watch. Affects stimulus generation, per-participant CIs, and t.test z-maps. Serial runs were never affected and are unchanged.

This required swapping the foreach backend from doParallel to doSNOW, which is the one that can report task completions back to the parent session. doParallel is no longer a dependency; doSNOW and snow take its place, for slightly less installed than it took. Nothing about how the loops compute changes, and no numeric output changes.

• The base_face_files type check raises an error you can actually read. It wrote its explanation to stderr() and then called stop() with no arguments, so the condition it raised carried an empty message: conditionMessage() returned "", and anything wrapping the call — a Shiny app, a batch script, knitr — caught an error it could not report. Under sink() or capture.output(type = "message") the explanation could be separated from the failure entirely. The text now travels with the condition.

• A base image that cannot be read is reported with the file it came from. The reader's own complaint (file is not in PNG format, and the like) is kept and prefixed with the entry's name and path, and a file that does not exist is now reported as missing rather than as unopenable.

• Base images are validated before the noise basis is built and before the output directory is created. A mistyped path used to cost the full noise-pattern computation — appreciable at the default 512px — and left an empty stimulus directory behind before reporting the problem.

No numeric output changes. Every check here either replaces an error with a clearer error, or rejects input that could not have produced correct stimuli; a call that succeeds today produces exactly what it did before.

• A multi-channel PNG mask one pixel wide or tall is now rejected instead of silently masking everything. Dropping the colour channel from such a mask also dropped its singleton spatial dimension, leaving a plain vector whose absent dimensions made the size check pass vacuously; the mask was then recycled by linear indexing. A 1-by-8 RGB mask against an 8-by-8 stimulus set returned an entirely NA classification image with no error or warning. It now fails the size check and says so. Masks of any other shape are unaffected.

• generateCI(mask = ...) no longer crashes on a greyscale-plus-alpha PNG mask. The internal mask importer hardcoded three colour channels, so any 2-channel PNG (the form png::readPNG() produces for 8-bit greyscale-plus-alpha) failed with subscript out of bounds rather than a clean error — plotZmap(mask = ...)'s separate, now-removed mask code already accepted the same file. Mask import is now shared between the two functions (#185), so both accept a 2-channel mask, and a 4-channel (RGBA) mask continues to work exactly as before. The mask-size-mismatch message now names what the mask is being checked against ("stimuli" from generateCI(), "z-map" from plotZmap()) instead of always saying "stimuli", and reports the mask's dimensions in the same row-by-column order as the target's rather than transposed.

Documentation

• ?computeCumulativeCICorrelation explains what its curve ending at 1 does and does not mean. With no targetci, the final CI it compares against is built from the same un-aggregated trials as the curve, so wherever the evaluated trials reach the last one the curve ends at 1 — self-consistency, not convergence. That is every call at the default step = 1, though a larger step can stop short of the final trial and end below 1, and responses that cancel exactly give a constant CI and an all-NA curve. That final CI is identical to generateCI()'s where every stimulus was presented the same number of times, and differs where repeat counts vary, because this function weights each trial equally while generateCI() weights each unique stimulus equally. Measured on an 8-trial set with counts 4/2/1/1, the two correlate at 0.77. Pass targetci = generateCI(...) when you want the curve to describe the CI you will report. Nothing changed in what the function computes.

• ?generateCI documents the weighting of repeated stimulus presentations. When participants is NA, repeated presentations are collapsed before building the CI: each unique stimulus gets equal weight, regardless of how many times it was presented. With equal repeat counts this changes nothing; with unequal counts it is a different estimand from weighting each trial equally, and the difference can be substantial. Previously this was described only as a performance optimisation in a code comment.

• There is now a documentation website: https://rdotsch.github.io/rcicr/. The function reference, both vignettes and this changelog are readable without installing the package first. It is generated from the same sources — README.md is the home page, so "How it works" and "Anatomy of the .Rdata file" are not maintained twice — and rebuilt by GitHub Actions on every push, so it cannot drift from the code.

• The repository now carries a CITATION.cff, so GitHub offers a "Cite this repository" button. citation("rcicr") is unchanged and still reads inst/CITATION, which remains the citation of record; the new file is generated from it and DESCRIPTION by cffr, and carries it as preferred-citation. The two cannot drift apart: CI regenerates the file, compares every field, and validates the result against the CFF schema.

• The install instructions now install a release rather than the development version. remotes::install_github('rdotsch/rcicr') takes the tip of main, which carries unreleased changes; the README.md and walkthrough-vignette instructions now lead with @*release, and show @v1.2.3 for installing one specific version — worth recording in an analysis script, since a classification image is only reproducible against the version that computed it.

• ?generateGabor now documents generateGabor(). Its example called generateSinusoid(), so the help page and the reference site demonstrated a call that never reached the function being documented; @return described a sinusoid rather than a gabor patch, and @param sigma was an unfinished sentence that did not say what the value means. sigma is the standard deviation of the Gaussian mask in pixels — measured, not inferred: the mask falls to exp(-1/2) at 24.5 px from centre for sigma = 25. The function itself is unchanged.

Internal

• The pre-0.3.0 0-indexed noise path is now pinned against an independent oracle. Reading a .Rdata file whose patch indices start at 0 takes a backward-compatibility branch in generateNoiseImage() that drops the 0-indexed cells and recycles a too-short weight vector — which looks like it could misalign the whole image. It does not: the last patch layer is all-zero, so the recycled values land only where the patch is zero and are multiplied away. A test confirms the output equals the honest "one patch not shown" result exactly, so no change to the indexing can silently reintroduce a misalignment. No behaviour changes.

• Stimulus sets generated by 1.0.1 and 1.1.0 are now covered by tests. The suite carries .Rdata files those releases actually wrote — generated by installing each tag, not reconstructed — and checks that the current generateCI() still reads them and produces a classification image. A 1.0.1 file predates nscales, so generateReferenceDistribution2IFC() has to assume it: the test asserts the null it builds is bit-identical to one from a file that states nscales outright, because a null built on the wrong noise basis finishes just as happily and is wrong. (The parallel sigma fallback only affects Gabor noise, which these sinusoidal fixtures do not exercise — tracked separately.) Every other fixture is built by the current generator, so nothing before this could catch a field this version expects and an older one never saved. It runs on every platform with no network: the fixtures are 205 KB (1.0.1) and 45 KB (1.1.0).

rcicr 1.2.3 (2026-08-08)

Documentation only. Nothing this package computes has changed — no function, argument, return value or number differs from 1.2.2, and no analysis script needs revisiting.

The release exists because the package-level help page, ?rcicr, had gone stale enough to contradict the release before it. It was a hand-maintained .Rd file that roxygen never touched, so the sweeps behind 1.2.2 — which all worked from R/ — went straight past it. Every code snippet on it was wrong:

• Two of the three example calls, generateStimuli2IFC(base_face_files, n_trials = 770) and generateCI2IFC(stimuli, responses, baseimage, rdata), would now error: they omit the write paths that 1.2.2 made required.
• The third, autoscale(cis, saveasjpegs = TRUE), named an argument that has never existed under that spelling. It is save_as_pngs.
• The page twice promised output "saved as jpegs to a folder called stimuli in your current working directory" — the writing-by-default behaviour that 1.2.2 removed, and in a format the package does not write.
• Its \examples section was a single commented-out line, #simple examples will be added soon., left over from 2016.
• It carried a hand-typed Version: 0.4.0 and Date: 2017-07-25, five releases and nine years out of date.

The page is now generated by roxygen from R/rcicr-package.R, so its title, description, author and URLs come from DESCRIPTION and cannot drift from it again. The version and date table is gone rather than corrected — the way to keep a fact current is to stop writing it down twice. What remains is a short pointer to vignette("reverse-correlation-walkthrough") and to the three functions a new user starts with; the walkthrough itself lives in the vignette and README.md, which are tested on every build.

The page also now lists all three key references — Dotsch & Todorov (2012), Brinkman, Todorov & Dotsch (2017), and Dotsch, Wigboldus, Langner & Van Knippenberg (2008) — each with a DOI. The 2008 paper had been on the old page and was the only one not carried anywhere else.

?rcicr and package?rcicr both still work.

rcicr 1.2.2 (2026-08-07)

This release exists to answer the changes CRAN asked for when reviewing the previous submission. Nothing it changes affects a number this package computes: classification images, scaling, z-maps and informational value are identical to 1.2.1, and the release gate confirms that against both 1.2.1 and 1.0.1.

Breaking changes

• Functions that write files now require you to say where. stimulus_path (generateStimuli2IFC()), targetpath (generateCI(), generateCI2IFC(), batchGenerateCI(), batchGenerateCI2IFC(), autoscale(), plotZmap()) and zmaptargetpath (generateCI()) have lost their defaults. They used to be ./stimuli, ./cis and ./zmaps, which meant a default call created directories in whatever your working directory happened to be — writing to your filespace without being asked, which CRAN policy does not permit.

What to change in your scripts. If you relied on the old defaults, name them:

``` r # before generateCI(stimuli, responses, "face", rdata)

# after generateCI(stimuli, responses, "face", rdata, targetpath = "./cis") ```

You will not silently get files somewhere new — a call that would have written to a default path now stops with an error naming the argument to supply. If you do not want files at all, save_as_png = FALSE (or save_as_pngs = FALSE for autoscale()) needs no path.

Bug fixes

• batchGenerateCI() no longer produces a spurious CI for rows with no group. Rows whose by column was NA were kept and collapsed into an extra group named after NA, so a data frame with any missing grouping value returned one more classification image than it had groups — computed from whatever rows happened to be missing that value. batchGenerateCI2IFC() has always dropped those rows; the two now agree.

• generateCI(mask = ) accepts a logical matrix. The matrix branch tested typeof(mask) == 'double', so a mask built the obvious way — as TRUE/FALSE rather than 1/0 — fell through to The mask argument is neither a string nor a matrix!, despite the documentation describing exactly that form. It is now tested with is.matrix().

• generateCI() and computeCumulativeCICorrelation() no longer print the entire base image when they cannot find stimulus parameters. The "No parameters found for base image" error named the base image matrix where its label was meant. Because paste0() is vectorized, this did not paste one matrix into one message — it built one complete message per pixel, so the error came back as 1,024 concatenated copies at a 32x32 base image (8,190 characters) and roughly 7 MB at the 512x512 size researchers actually use, with the reason for the failure buried inside it. The message now reads, in full, No parameters found for base image: <label>.

Only the text of an error changed. No function's return value, arguments or numeric output are affected, and the condition that triggers the error is unchanged — if your analysis script runs today, it behaves identically.

• generateReferenceDistribution2IFC() no longer leaves a stray stimuli directory behind. It re-derives the noise basis by calling generateStimuli2IFC() with both save options off, purely to work in memory — but the directory was created before either option was consulted, so every call to it, and to computeInfoVal2IFC() when no reference distribution was cached, created an empty ./stimuli wherever you happened to be working.

• plotZmap() restores the graphics parameters it changes. The undecorated branch set par(mar = ...) and left it set. It also now closes its PNG device through on.exit(), so a failure part-way through plotting can no longer leak the device or leave a half-written file.

Documentation

• The DESCRIPTION description no longer opens with the redundant "Functions to", and cites the two method references: Dotsch and Todorov (2012) and Brinkman, Todorov and Dotsch (2017) .

• Every example runs. The \donttest{} wrappers are gone from all eight examples that carried them, simulateNoiseIntensities()'s \dontrun{} is gone, and generateNoiseImage()'s example is real code rather than three commented-out lines that would not have worked (p was never defined, and params was the wrong length for the pattern). The whole example set now runs in about nine seconds.

• simulateNoiseIntensities()'s note claiming the function always errors is removed. It described two bugs that were fixed in 1.1.0; the note was left behind.

Internal

• Bare T and F are replaced by TRUE and FALSE throughout R/. Two of these were public API defaults visible in the documentation (generateCI(zmap =, zmapdecoration =) and plotZmap(decoration =)); the values are unchanged.

• The guard that keeps a function's arguments across load() is now a shared helper, captureArgs(). It skips required arguments that were not supplied — necessary once paths became required, since mget() forces the promise and a wrapper forwarding its own missing argument would abort there. Defaulted arguments are still captured: missing() reports those missing too, and their default is exactly as vulnerable to being replaced by a field in the .Rdata file as a value passed explicitly.

• The failure paths are tested. The suite had 9 assertions covering 33 stop() and warning() calls, so most of the package's error messages had never been run. They now are: the stimuli/responses length mismatch, every "this .Rdata file did not contain X" guard in generateCI() and computeCumulativeCICorrelation(), all four mask-import failures, and base images that are unreadable or not square. No behaviour changed — this is coverage of messages that were already there. It matters because an unexercised guard is indistinguishable from one that works, which is how three separate bugs in this package stayed live for years, the most recent being the one fixed just above.

• Every function that reads a stimulus set now keeps its arguments across the load(). load() assigns straight into the calling function's frame, so an object stored in an .Rdata file silently replaces an argument of the same name. generateCI() and generateReferenceDistribution2IFC() already guarded against this; computeInfoVal2IFC() guarded three of its five arguments, and computeCumulativeCICorrelation() none.

No file this package has ever written triggers the problem, so no result changes and no analysis needs revisiting — the guard is preventive. It is worth having because the one collision that did occur (the z-map sigma, fixed in 1.2.0) was created by adding a field to the file, not by adding an argument, so an argument that is safe today stops being safe without anything in the function changing. The case now closed in computeInfoVal2IFC() is the one that would have mattered most: target_ci is read at the very end to compute the CI norm, and after a second load(), so a file carrying that name would have scored a different classification image and returned a plausible number rather than an error.

rcicr 1.2.1 (2026-07-28)

No user-facing changes. Nothing this package computes differs from 1.2.0 — no function, argument, return value or number has changed, and no analysis script needs revisiting.

The release exists because the 1.2.0 source tree does not pass R CMD check on macOS. The fault was in the package's own test suite, not in the package: a test asserted properties of a rendered PNG that belong to the graphics device rather than to what was drawn, and those properties differ between macOS and Linux. No released function was ever affected. A package still has to pass its own checks on the platforms CRAN builds for, which is what this release restores.

Documentation

• ?plotZmap and the README now describe what is and is not reproducible across operating systems. Classification images, scaling, informational value and the z-scores themselves are ordinary R arithmetic and do not depend on your platform — as of this release that is verified on Linux, macOS and Windows on every change, rather than assumed. The PNG written by plotZmap() is the one exception: it is drawn through a graphics device, and devices differ by platform in colour management and in whether they write an alpha channel, so the same z-map produces visibly identical figures whose files are not byte-identical.

The practical advice, now stated in both places: compare numbers, not rendered figures, when checking that an analysis reproduces. A z-map image that differs pixel-for-pixel on a colleague's machine is not a different result. Every other PNG the package writes — stimuli, classification images, autoscaled classification images — is written directly from the pixel array and carries no such dependence.

Internal

• R CMD check now runs on macOS and Windows as well as Linux, on every change. It previously varied only the R version against a single platform, which is how the macOS failure above went unnoticed.
• The test suite pins z-map values as well as classification images, scaling and informational value, so cross-platform agreement of the numbers is checked rather than assumed.

rcicr 1.2.0 (2026-07-28)

Upgrading from the CRAN version? The last release on CRAN was 0.3.4.1, before the package was archived in 2021. 1.0.1 and 1.1.0 were GitHub-only releases made in the meantime, so the 1.1.0 section below applies to you too — it is where the bulk of the bug fixes are.

Reproducibility impact

• generateCI(zmap = TRUE) blurred z-maps with the wrong sigma, for stimulus sets generated with 1.1.0 only. generateCI() reads the stimulus set with load(), which assigns into the function's own frame, and 1.1.0 began storing the noise sigma there — the same name as the z-map blur argument. The saved value replaced the argument, so z-maps were blurred with 25 rather than the documented 3, and passing sigma did nothing.

In practice this affects nobody. 1.1.0 was a GitHub tag that stood for about a day and was never on CRAN, so almost no stimulus set carries the field that triggers it. Files from 1.0.1 and earlier have no sigma at all and were never affected. Only z-maps are involved — classification images, scaling, InfoVal and every saved number are untouched. It is recorded here because it did change a number, and because if you are the one person who generated stimuli that day, regenerating the z-map is a one-line rerun.

Every argument is now kept across the load(), so a field added to the .Rdata later cannot quietly capture another one. Found by tools/compare-release-output.R, the release gate introduced in this version — the first bug it caught.

Behaviour change

• plotZmap(mask = ...) now actually masks the z-map. The argument has been documented since 2016 — "if a cell evaluates to TRUE, the corresponding zmap pixel will be masked" — and until now it did nothing at all: the mask was read from its PNG or matrix, checked against the z-map's dimensions, validated as binary, converted to boolean, and then discarded before plotting. A correct mask produced an unmasked z-map, with no error and no warning. Masked cells are now dropped from the z-map exactly as sub-threshold cells are.

Who is affected. Only direct calls to plotZmap(mask = ...). generateCI() does not pass mask to plotZmap() — it masks the classification image itself, via a separate and working code path — so z-maps produced through the normal pipeline are unchanged, and no stored numbers change anywhere. If you have been passing a mask and your z-maps looked unmasked, that is why; they will now come out masked, and the earlier images were wrong about which regions carry signal.

A second bug is fixed alongside: the conversion to boolean set every cell to FALSE whatever you passed, so even once applied the mask would have masked nothing.

• The mask convention is documented correctly for the first time, in both ?plotZmap and ?generateCI. Both said a matrix masks where the value is 1/TRUE while a PNG masks where it is black (0) — two opposite conventions in one sentence. generateCI()'s implementation has always masked where the value is 0, for a matrix and a PNG alike, so the matrix half of the documentation was simply wrong. The code is unchanged and the documentation now matches it, since existing masks were built against the behaviour, not the prose. plotZmap() follows the same single convention, so one mask can be passed to both functions — which is now asserted by a test rather than assumed.

If you built a mask by reading ?generateCI rather than by looking at your output, check it: 0/black/FALSE is the region that gets masked away.

New features

• generateReferenceDistribution2IFC() and computeInfoVal2IFC() gained a response_seed argument, so the null distribution InfoVal is scored against can be varied deliberately. Until now there was no way to draw a second, independent null from the same stimuli — which meant you could not check how much Monte Carlo error your choice of iter was leaving in your InfoVal. response_seed seeds the simulated responses only; the stimuli, and so the noise basis the null is built on, are untouched.

Existing calls are unaffected. The default (NULL) issues no set.seed() call at all, so the reference distribution is byte-identical to what earlier versions produced. Verified against norms generated before the change, not merely assumed.

In computeInfoVal2IFC(), passing response_seed forces the reference distribution to be regenerated even when the .Rdata file already holds one, and the result is deliberately not written back — a one-off check of the Monte Carlo error cannot silently become the number every later analysis of that stimulus set reports.

• generateReferenceDistribution2IFC() gained save_rdata (default TRUE, i.e. unchanged) and now returns the reference distribution invisibly instead of returning nothing, so the norms are reachable when you ask it not to write them to the .Rdata file.

• The .Rdata file gained a reference_norms_seed field recording the response_seed the stored reference_norms were generated with (NULL for the default). Purely additive; files written by earlier versions simply lack it. A stimulus set carrying a deliberately varied null is no longer indistinguishable from one carrying the default.

Bug fixes

• autoscale() works on masked classification images. generateCI(mask = ...) sets masked pixels to NA by design, and autoscale() took a bare range() over them, so the scaling constant became NA and the call died with missing value where TRUE/FALSE needed. The scaling constant is now computed from the unmasked pixels, exactly as generateCI()'s own scaling has always done, and masked pixels stay masked in the result. A CI that is entirely NA now raises an error naming the CI instead of failing the same opaque way.

• generateCI() accepts a pre-0.3.0 .Rdata file when computing a CI from a single trial. rcicr 0.3.0 stopped drawing four random contrasts per trial that no patch index ever referred to (4096 → 4092), and generateCI() has truncated older files ever since — but the single-trial branch tested for a length of 4092 and then truncated to 4092, a no-op that could never fire on the 4096-parameter input it existed for. Such a call failed with Stimulus generation aborted: number of parameters doesn't equal number of patches!. The multi-trial path was always correct and is unchanged.

• computeInfoVal2IFC() and generateReferenceDistribution2IFC() work on .Rdata files written before noise_type was saved (#94). Such a file failed outright with object 'noise_type' not found, and the workaround on record was to load the file and assign the variable by hand. It now falls back to sinusoid with a loud warning, matching how nscales is handled — a warning rather than a silent default, because guessing wrong means the null is built on a different kind of noise than participants saw, and the resulting InfoVal would be wrong. Files written by 1.1.0 or later already store the field and are unaffected.

• generateStimuli2IFC(return_as_dataframe = TRUE) shows its progress bar (#82). The return handing back each trial's noise exits the entire loop body, so it jumped past the progress-bar update and the bar sat at zero for the whole run — on the slowest path there is, since generateReferenceDistribution2IFC() takes it for every InfoVal.

• The .Rdata file written by generateStimuli2IFC() now records the rcicr version that actually wrote it (#29). generator_version was a hardcoded '0.4.0' string from 2016 onwards, so every file produced by 0.4.0 through 1.1.0 claims to come from 0.4.0 — useless for the provenance the field exists for, and it disagreed with p$generator_version, which held the real version all along.

No result changes: nothing in the package has ever read this field. If your own code does, note two things. Existing files cannot be trusted to say what wrote them, so treat a stored '0.4.0' as "unknown, somewhere between 0.4.0 and 1.1.0" rather than as a version. And the field is now a package_version object rather than a character string, so compare with utils::packageVersion() or numeric_version(), never as text — '0.10.0' < '0.4.0' is TRUE when compared as strings.

Documentation

• README.md now describes the package's architecture and, more usefully, the anatomy of the .Rdata file field by field. That file is the only link between stimulus generation and analysis — nothing about a stimulus set is recoverable without it — and until now its contents were documented nowhere a user would look.

• A CONTRIBUTING.md sets out how to work on the package, leading with the constraint that makes it unusual: researchers re-run old analysis scripts years later and publish the results, so numeric output must not change silently.

• ?generateStimuli2IFC documents a restriction on return_as_dataframe = TRUE: the frame holds one noise image per trial, so it is meaningful only under the default use_same_parameters = TRUE. With use_same_parameters = FALSE and more than one base image, only the first base image's noise comes back — the frame's shape cannot represent trial × base image. Behaviour is unchanged, and the files written to disk were never affected; the restriction simply was not stated.

• ?generateReferenceDistribution2IFC now documents as a guarantee what was previously only true by accident: with the default response_seed, the reference distribution — and therefore InfoVal — is reproducible from the stimulus .Rdata file alone, independent of the calling session's random number state and of ncores. This held before, but nobody had chosen it: it is a consequence of generateStimuli2IFC()'s internal set.seed() landing before the simulation draws. That call now carries a comment saying what depends on it, so it is not moved casually.

rcicr 1.1.0 (2026-07-27)

First release since 1.0.1, and the version submitted to CRAN to reinstate the package after its 2021 archival. The minor bump rather than 1.0.2 is deliberate: some of the changes below alter behaviour rather than only repairing it. The public API is unchanged — no function, argument or argument meaning was removed or redefined — so a 2.0.0 is not warranted. Anyone re-running an old analysis script should read the "Reproducibility impact" section below.

Bug fixes

• generateCI(zmap = TRUE, zmapdecoration = FALSE) works at all. The undecorated branch of plotZmap() tested its background image with if (bgimage != ''), a condition of length img_size^2, which R >= 4.2 treats as an error rather than silently taking the first element. generateCI() always supplies a background image, so this path could never run. Same root cause as the mask bug above; the decorated branch already used identical().
• plotZmap(decoration = FALSE) works on small images. plot.new() was called before the margins were reset to zero, and it rejects a device too small to hold the default margins, so any z-map below roughly 100 pixels failed with figure margins too large. Rendered output at usual sizes is unchanged.
• generateCI(zmaptargetpath = ...) is honoured. The argument was documented and accepted but never forwarded to plotZmap(), so z-maps were always written to ./zmaps relative to the working directory regardless of what was requested.
• generateStimuli2IFC() now validates that the base image matches img_size, with an error naming the file and both sizes, instead of failing inside a parallel worker with non-conformable arrays (#124).
• The mask argument of generateCI() works again. It was unusable on R >= 4.2, was restricted to 512px stimuli by a hardcoded size check, and rejected greyscale-as-RGB PNG masks even when it had successfully converted them.
• generateCI(), batchGenerateCI() and computeCumulativeCICorrelation() accept tibble columns, not only data.frame columns (#70, #123). generateCI() also checks that stimuli and responses are the same length up front.
• generateStimuli2IFC() saves nscales and sigma to the .Rdata file, and generateReferenceDistribution2IFC() uses them (#81). See below.
• computeInfoVal2IFC(force_gen_ref_dist = TRUE) regenerates the reference distribution instead of silently reusing the cached one (#113).
• generateNoiseImage() accepts pre-0.3.3 .Rdata noise patterns using the sinusoids/sinIdx layout. This backward-compatibility path had never worked.
• simulateNoiseIntensities() runs at all, and honours its img_size argument.
• generateReferenceDistribution2IFC() gained an ncores argument instead of always using detectCores() - 1.
• computeInfoVal2IFC() no longer creates a stray file called data in your working directory. One write() call omitted its destination, and base R's write() defaults to file = "data" — so the "reference distribution has been saved" message was written to that file instead of the console.
• generateCI() accepts a greyscale-encoded RGB PNG as a mask. The conversion worked, but the error for genuinely non-greyscale images was raised unconditionally afterwards, so every such mask was rejected anyway.
• generateReferenceDistribution2IFC() no longer writes its own arguments into the .Rdata file it updates. load() assigns straight into the calling function's frame, so a stored rdata (or, newly, ncores) object overwrote the argument of the same name on the next call — meaning a second call ignored the ncores you passed and wrote back to the path recorded during the first call. computeInfoVal2IFC() additionally guards against this when reading .Rdata files written by older versions, which still contain the stale path.

Performance and dependencies

• generateStimuli2IFC() no longer preallocates the full stimulus array before starting its parallel workers. At the default 512px / 770 trials that array was ~1.5 GB, and foreach copied it to every worker, which each wrote one slice into and discarded. Addresses issue #12.
• Parallel clusters are now stopped via on.exit(), so workers are released even when an error interrupts the loop. Fixes the "closing unused connections" warnings (issue #50).
• generateNoiseImage() is about 6x faster — 1.66s to 0.28s per call at the default 512px with nscales = 5 — and allocates about 30% less memory. The per-pixel average across patch layers is now computed with rowMeans(..., dims = 2) instead of apply(..., 1:2, mean); that step alone is ~31x faster, and what remains is building the weighted patch array, which is unavoidable. Because this function is called for every trial during stimulus generation and again for every CI and z-map, the saving compounds. Thanks to @hvalev, who diagnosed this and benchmarked it in #122. See "Reproducibility impact" below — the result is not bit-identical to the old one.
• ncores = 1 no longer builds a cluster. The parallel loops in generateStimuli2IFC() and generateCI() previously started a one-worker cluster even when asked for a single core — a second R process, loading the package, receiving each iteration and sending it back. They now run in the current process. The test suite went from 140s to 4s, and R CMD check from [8s/126s] on tests (eight seconds of CPU against 126 elapsed, over 22 cluster spawns) to a fraction of that. Results are unaffected and this is verified rather than asserted: ncores = 1 and ncores = 2 produce bit-identical stimulus parameters, noise bases and classification images, now pinned by tests/testthat/test-parallel-equivalence.R. Neither loop draws random numbers — parameters are drawn under set.seed() before the loop — so there is no worker RNG stream to diverge. Addresses the remainder of issue #50's neighbourhood.
• Imports shrank from 27 packages to 15; none of the removed ones were used.
• Deprecated calls replaced: dplyr::progress_estimated(), purrr::rbernoulli(), and citEntry()/personList() in inst/CITATION. The rbernoulli() replacement was chosen to preserve the random number stream exactly — see below.

Reproducibility impact — read this if you have published or in-progress results

This release fixes several long-standing bugs. Most of them turn a crash into working behaviour, and therefore cannot change any result you already have — if the old code errored, there was no number to change.

Only two fixes can change a value you may already have reported. Both are listed first, with the exact conditions under which they apply.

A golden-master test (tests/testthat/test-regression-baseline.R) pins the numeric output of the default pipeline — noise basis, classification image, scaling, and infoVal — to the values produced before these fixes. It passes, which is the evidence for the claim that default-configuration results are unchanged.

Results CAN differ

1. infoVal, if you used a non-default nscales (issue #81)

generateStimuli2IFC() did not save nscales or sigma into the .Rdata file. generateReferenceDistribution2IFC() re-generates the stimulus set from that file to build the infoVal null distribution, so with nscales missing it silently fell back to the default nscales = 5 — building the reference distribution on a different noise basis than the stimuli participants actually saw.

• Affected: anyone who called generateStimuli2IFC(..., nscales = <not 5>) and then reported an infoVal (or sigma with noise_type = "gabor").
• Not affected: the default nscales = 5, where the fallback happened to coincide with the real value. This is the common case.
• After the fix: infoVal for affected stimulus sets will change, because it is now computed against the correct null distribution. The old value was wrong.
• What to do: if this applies to you, recompute infoVal. Old .Rdata files do not contain nscales, so the fix warns rather than guessing — regenerate the stimulus set, or pass the value explicitly.

2. infoVal, if you passed force_gen_ref_dist = TRUE (issue #113)

The flag was silently ignored whenever a reference_norms vector already existed in the .Rdata file, so the reference distribution was reused rather than recomputed.

• Affected: anyone who passed force_gen_ref_dist = TRUE expecting a fresh simulation. You received the cached distribution instead.
• Not affected: the default force_gen_ref_dist = FALSE, which was always meant to reuse the cache.
• After the fix: the flag regenerates the distribution, so infoVal will differ from a cached run. Because the reference distribution is simulated, it also varies slightly between regenerations — that is expected.

Results cannot differ

These fixes only affect code paths that previously errored out, so no previously obtained result changes:

• Tibble inputs to generateCI() (issues #70, #123) — previously failed with arguments must have same length.
• The mask argument — previously failed on R >= 4.2 with the condition has length > 1, and was restricted to 512px stimuli by a hardcoded size check.
• Base images not matching img_size (issue #124) — previously failed inside a parallel worker with non-conformable arrays.
• Pre-0.3.3 .Rdata files using the sinusoids/sinIdx layout — the backward-compatibility path was unreachable and always errored.
• simulateNoiseIntensities() — errored on every call.
• Arguments overwritten by load() — only reachable if you renamed or moved an .Rdata file between calls, in which case the old code either errored with cannot open the connection or wrote the reference distribution back to the file's former path. The ncores half affects speed only. No infoVal changes.

Changed, but below any scale that can matter: the patch average

generateNoiseImage() now averages patch layers with rowMeans(..., dims = 2) rather than apply(..., 1:2, mean). These compute the same quantity but sum in a different order, so they are not bit-identical: they differ by about one unit in the last place, ~1e-19 in absolute terms on pixel values of order 0.01.

This is a different class of thing from the rbernoulli case below. That one would have changed the random stream — a large, systematic divergence. This is floating-point summation order, and it was checked against an independent oracle (the average written as an explicit triple loop, using neither apply() nor rowMeans()) across noise types, spatial scales and seeds: both the old and new forms sit ~5.6e-17 from that oracle. Neither is "more correct" than the other.

• Affected: nothing you would report. No CI, z-map, infoVal or scaling decision changes at any precision a paper prints, and the difference is far below the noise you would get from re-running with a different seed.
• At the configuration the golden master pins, the results came out bit-identical.
• It is recorded here anyway, because the standard for this package is that any numeric change is written down rather than discovered later by someone re-running a five-year-old script.
• tests/testthat/test-generateNoiseImage.R now pins the new implementation against the original apply() form across 12 configurations, so it cannot drift further.

Deliberately unchanged: the random number stream

purrr::rbernoulli(n, p) (deprecated) is internally runif(n) > (1 - p). The obvious modern replacement, rbinom(n, 1, p), draws from the stream differently — verified across 150 seed/probability combinations that the two diverge. Swapping it in would have silently changed every reference distribution, and therefore every infoVal, computed from a given seed. The runif form is used instead, verified bit-identical to the old behaviour.

Unchanged and verified

• The infoVal formula itself. rcicr already implements the corrected version from the erratum to Schmitz et al. (2019): the Euclidean norm, with the k constant supplied by R's mad() (constant = 1.4826). This was fixed years ago; it is now covered by a regression test so it cannot silently drift.
• The noise basis (generateNoisePattern()), the stimulus parameter draw, and all four scaling methods, for the default configuration.

Changes before 1.1.0 are recorded in ChangeLog, which is frozen at 1.0.1 and covers the package back to 2014, including its CRAN era.

rcicr documentation built on Sept. 27, 2026, 5:07 p.m.