# distractor.analysis {CTT}

### Description

This function performs distractor analysis for each item.

### Usage

distractor.analysis(items, key, scores, p.table = FALSE, write.csv)

### Arguments

- items
- The unscored item response from a multiple-choice test
- key
- The answer key for the items
- scores
- An optional set of person scores associated with the item data. If scores are not provided (default) the scores are calculated using the item data and key.
- p.table
- If p.table=FALSE (the default) the function returns the counts of examinees who provide each answer. If p.table=TRUE the function returns the proportion of examinees who provide each answer.
- write.csv
- If the optional file name is provided the function will save a .csv file with the results.

### Details

The scores are used to split respondents into terciles. The number (or proportion if p.table=TRUE) of examinees in each tercile giving each response is reported. The correct answer is indicated with an "*".

### Values

If p.table=F counts of respondents in each tercile who chose each answer is returned as a list of tables. Each item is a separate element in the list. If p.table=T the tables contain the proportion of respondents who chose each corresponding answer.

### References

Allen, M. J. & Yen, W. M. (1979). Introduction to Measurement Theory. Lon Grove, Illinois: Waveland Press, INC.

### Examples

Documentation reproduced from package CTT, version 2.1. License: GPL (>= 2)