ARC_correct: Adjusted Ratio of Clustering (ARC) - Correct Recall

In ggreeley/MemoryOrg: (A Few) Retrieval Organization Metrics for Human Memory Research

Description

Adapted from Roenker, Thompson, & Brown (1971). Computes ARC using the correct recall (N) of an individual or group. Also produces several other out-dated measures of category clustering and the componets of ARC (E(r), N, Repetitions, and Max).

Use when:

You want correct (1) items counted toward N - AND

There are NO intrusions present in data - OR

You want intrusions (blank NAs) to count as their own category but NOT toward N.

See "details" for more on the formula, notation definitions, and further explanation.

Usage

ARC_correct(correct, category)

Arguments

correct	Numeric vector representing correct (1) and incorrect (0) responses.
category	Numeric or character vector representing category membership of associated item in x column.

Details

ARC = [r − E(r)] / [max − E(r)]

E(r) = [ (∑ni^2) / N ] − 1

r = number of category repetitions

N = number of recalled items (ONLY correct)

c = number of recalled categories (including intrusions)

max = N − c and

ni = number of items recalled in each recalled category (including intrusions)

General - This will count category repetitions (but NOT repeated blank (NA) entries) and the correct N is used in all computations (max and E(r)) - BUT, blanks (NAs) will count as a category in E(r). Be sure data is properly processed (according to your protocol) before using.

Author(s)

Garrett. D Greeley

Ph.D. Student - Cognitive Science

Stony Brook University, NY

References

Roenker, D. L., Thompson, C. P., & Brown, S. C. (1971). Comparison of measures for the estimation of clustering in free recall. Psychological Bulletin, 76(1), 45–48. https://doi.org/10.1037/h0031355

See Also

ARC_correct_intrude()

ARC_total()

ARC_total_intrude()

Examples

Data adapted from Roenker et al. (1971) - Also see ARC_3SE and other example data in the package for more examples and formatting.

recall_correct <- c(1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)
recall_category <- c("a","a", NA ,"a","a","b","a","c","b","b","b","b","c","b","c","c","c","c")

ARC_correct(recall_correct, recall_category)

ggreeley/MemoryOrg documentation built on Aug. 8, 2020, 10:43 p.m.