Science {mirt}

R Documentation

Description of Science data

Description

A 4-item data set borrowed from ltm package in R, first example of the grm() function. See more complete documentation therein, as well as Karlheinz and Melich (1992).

Author(s)

Phil Chalmers rphilip.chalmers@gmail.com

References

Karlheinz, R. and Melich, A. (1992). Euro-Barometer 38.1: Consumer Protection and Perceptions of Science and Technology. INRA (Europe), Brussels. [computer file]

Examples

## No test: 
itemstats(Science)

## $overall
##    N mean_total.score sd_total.score ave.r  sd.r alpha SEM.alpha
##  392           11.668          2.003 0.275 0.098 0.598      1.27
## 
## $itemstats
##           N  mean    sd total.r total.r_if_rm alpha_if_rm
## Comfort 392 3.120 0.588   0.596         0.352       0.552
## Work    392 2.722 0.807   0.666         0.332       0.567
## Future  392 2.990 0.757   0.748         0.488       0.437
## Benefit 392 2.837 0.802   0.684         0.363       0.541
## 
## $proportions
##             1     2     3     4
## Comfort 0.013 0.082 0.679 0.227
## Work    0.084 0.250 0.526 0.140
## Future  0.036 0.184 0.536 0.245
## Benefit 0.054 0.255 0.492 0.199

mod <- mirt(Science, 1)
plot(mod, type = 'trace')

## End(No test)

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