# observed: Observed test statistic In SCRT: Single-Case Randomization Tests

## Description

The observed test statistic is calculated from the obtained raw data.

## Usage

 `1` ```observed(design, statistic, data = read.table(file.choose(new = FALSE))) ```

## Arguments

 `design` Type of single-case design: `"AB"`, `"ABA"`, `"ABAB"`, `"CRD"` (completely randomized design), `"RBD"` (randomized block design), `"ATD"` (alternating treatments design), `"MBD"` (multiple-baseline AB design) or `"Custom"` (user specified design). `statistic` Test statistic. For alternation designs, multiple-baseline designs and AB phase designs, there are 3 built-in possibilities: `"A-B"`, `"B-A"`, and `"|A-B|"`, which stand for the (absolute value of the) difference between condition means. For phase designs with more than 2 phases, 6 more built-in options are available: `"PA-PB"`, `"PB-PA"`, and `"|PA-PB|"` refer to the (absolute value of the) difference between the means of phase means, and `"AA-BB"`, `"BB-AA"` and `"|AA-BB|"` represent the (absolute value of the) difference between the sums of phase means. Additionally, it is possible to specify a custom test statistic using the variable identifiers `"A"` and `"B"` (or in the case of phase deisgns with more than 2 phases, `"A1"`, `"B1"`, `"A2"`, `"B2"`, `"A"` and `"B"`) and any of the basic R functions. For example, `"abs(mean(A) - mean(B))"` can be used as a test statistic and it will be the same as using `"|A-B|"`. `data` File in which the data can be found. Default: a window pops up in which the file can be selected.

## Details

When using the default `data` argument, a window will pop up to ask in what file the data can be found. This text file containing the data should consist of two columns for single-case phase and alternation designs: the first with the condition labels and the second with the obtained scores.

For multiple-baseline designs it should consist of these two columns for EACH unit. This way, each row represents one measurement occasion. It is important not to label the rows or columns.

## References

Bulte, I., & Onghena, P. (2008). An R package for single-case randomization tests. Behavior Research Methods, 40, 467-478.

Bulte, I., & Onghena, P. (2009). Randomization tests for multiple baseline designs: An extension of the SCRT-R package. Behavior Research Methods, 41, 477-485.

`distribution.systematic` to generate the exhaustive randomization distribtion and `pvalue.systematic` to obtain the corresponding p-value.
`distribution.random` to generate the nonexhaustive randomization distribution and `pvalue.random` to obtain the corresponding p-value.
 ```1 2``` ```data(ABAB) observed(design = "ABAB", statistic = "AA-BB", data = ABAB) ```