# mu: Compute the expected test score by substituting probability... In TestGardener: Information Analysis for Test and Rating Scale Data

 mu R Documentation

## Compute the expected test score by substituting probability of choices for indicator variable 0-1 values. Binary items assumed coded as two choice items.

### Description

Compute the expected test score by substituting probability of choices for indicator variable 0-1 values. Binary items assumed coded as two choice items.

### Usage

``````  mu(index, SfdList, scoreList)
``````

### Arguments

 `index` Initial values for score indices in the interval [0,100]. A vector of size `N`. `SfdList` A numbered list object produced by a TestGardener analysis of a test. Its length is equal to the number of items in the test or questions in the scale. Each member of `SfdList` is a named list containing information computed during the analysis. `scoreList` A numbered list of length n. Each member contains the weights assigned to each option for that item or question.

### Value

A vector of test score values.

### Author(s)

Juan Li and James Ramsay

### References

Ramsay, J. O., Li J. and Siberg, M. (2020) Full information optimal scoring. Journal of Educational and Behavioral Statistics, 45, 297-315.

Ramsay, J. O., Li J. and Siberg, M. (2020) Better rating scale scores with information-based psychometrics. Psych, 2, 347-360.

### See Also

`scoreDensity`

### Examples

``````#  Example 1.  Compute expected sum score values for the
#  short SweSAT multiple choice test with 24 items and 1000 examinees
scoreList <- Quant_13B_problem_dataList\$scoreList
SfdList   <- Quant_13B_problem_parmList\$SfdList
index     <- Quant_13B_problem_parmList\$index
muvec     <- mu(index, SfdList, scoreList)
par(c(1,1))
hist(muvec,11)
``````

TestGardener documentation built on May 29, 2024, 3:31 a.m.