SLF {mirt} | R Documentation |
A 5-item data set analyzed by Bartholomew (1998). Data contains dichotomous responses (endorsement vs non-endorsement) from 1490 German respondents to five statements on perceptions of social life.
Phil Chalmers rphilip.chalmers@gmail.com
Bartholomew, D., J. (1998). Scaling unobservable constructs in social science. Journal of the Royal Statistical Society - Series C, 47, 1-13.
## No test:
# tabular format
data(SLF)
SLF
## social1 social2 social3 social4 social5 freq
## 1 0 0 0 0 0 156
## 2 0 0 0 0 1 26
## 3 0 0 0 1 0 14
## 4 0 0 0 1 1 9
## 5 0 0 1 0 0 127
## 6 0 0 1 0 1 26
## 7 0 0 1 1 0 66
## 8 0 0 1 1 1 16
## 9 0 1 0 0 0 174
## 10 0 1 0 0 1 35
## 11 0 1 0 1 0 36
## 12 0 1 0 1 1 13
## 13 0 1 1 0 0 208
## 14 0 1 1 0 1 65
## 15 0 1 1 1 0 195
## 16 0 1 1 1 1 129
## 17 1 0 0 0 0 8
## 18 1 0 0 0 1 2
## 19 1 0 0 1 0 1
## 20 1 0 0 1 1 3
## 21 1 0 1 0 0 4
## 22 1 0 1 0 1 4
## 23 1 0 1 1 0 18
## 24 1 0 1 1 1 9
## 25 1 1 0 0 0 8
## 26 1 1 0 0 1 2
## 27 1 1 0 1 0 5
## 28 1 1 0 1 1 3
## 29 1 1 1 0 0 19
## 30 1 1 1 0 1 10
## 31 1 1 1 1 0 31
## 32 1 1 1 1 1 68
# full dataset
full <- expand.table(SLF)
itemstats(full)
## $overall
## N mean_total.score sd_total.score ave.r sd.r alpha SEM.alpha
## 1490 2.166 1.324 0.187 0.076 0.536 0.902
##
## $itemstats
## N mean sd total.r total.r_if_rm alpha_if_rm
## social1 1490 0.131 0.337 0.482 0.251 0.510
## social2 1490 0.672 0.470 0.550 0.227 0.527
## social3 1490 0.668 0.471 0.632 0.335 0.458
## social4 1490 0.413 0.493 0.702 0.420 0.397
## social5 1490 0.282 0.450 0.578 0.281 0.493
##
## $proportions
## 0 1
## social1 0.869 0.131
## social2 0.328 0.672
## social3 0.332 0.668
## social4 0.587 0.413
## social5 0.718 0.282
mod <- mirt(full)
plot(mod, type = 'trace')
## End(No test)