Prepare Data

Import surveys, combine into single data frame, delete identifying information, assign IDs, and separate out by scale for item examination.

# https://hansjoerg.me/2018/04/23/rasch-in-r-tutorial/

knitr::knit_hooks$set(
   error = function(x, options) {
     paste('\n\n<div class="alert alert-danger">',
           gsub('##', '\n', gsub('^##\ Error', '**Error**', x)),
           '</div>', sep = '\n')
   },
   warning = function(x, options) {
     paste('\n\n<div class="alert alert-warning">',
           gsub('##', '\n', gsub('^##\ Warning:', '**Warning**', x)),
           '</div>', sep = '\n')
   },
   message = function(x, options) {
     paste('\n\n<div class="alert alert-info">',
           gsub('##', '\n', x),
           '</div>', sep = '\n')
   }
)

# load libraries ----------------------------------------------------------
library(stringi)
library(psych)
library(DT)
library(naniar)
library(UpSetR)
library(nFactors)
library(lavaan)
library(corrplot)
library(tidyr)

library(ggplot2)
library(dplyr)
library("eRm")
library("ltm")
library("difR")
library("psych")

# load data ---------------------------------------------------------------
# alt <- read.csv(file="UBelong Post-Survey Pitt OChem Spring 2022 Alternative Scales_April 28, 2022_12.34.csv", header=T)
# alt <- alt[-c(1,2),]
# alt$scale <- "alt"
# 
# orig <- read.csv(file="UBelong Post-Survey Pitt OChem Spring 2022 Original Scales_April 28, 2022_12.35.csv", header=T)
# orig <- orig[-c(1,2),]
# orig$scale <- "orig"
# 
# df <- rbind.data.frame(alt, orig)
# df <- subset(df, select = -c(1:19))
# names(df)
# myFun <- function(n) {
#   a <- do.call(paste0, replicate(5, sample(LETTERS, n, TRUE), FALSE))
#   paste0(a, sprintf("%04d", sample(9999, n, TRUE)), sample(LETTERS, n, TRUE))
# }
# df$id <- myFun(nrow(df))
# write.csv(df, file="imported_anonymized.csv", row.names = F)

df <- read.csv(file="imported_anonymized.csv", header=T)

# extract items -----------------------------------------------------------
# new items
EEochem <- subset(df, select=c(scale,grep("EEochem", colnames(df)))) # entry expectations
CCdisc <- subset(df, select=grep("CCdisc", colnames(df))) # classroom climate
IDochem <- cbind.data.frame(subset(df, select=c(scale,grep("IDochem", colnames(df)))), subset(df, select=grep("FASochem", colnames(df)))) # identity
CSochem <- subset(df, select=grep("CSochem", colnames(df))) # career satisfaction

# established scales
MSchem <- subset(df, select=c(scale,grep("MSchem", colnames(df)))) # discipline growth mindset (chemistry)
IPchem <- subset(df, select=grep("IPchem", colnames(df))) # instructor growth mindset (chemistry)
SEchem <- subset(df, select=grep("SEchem", colnames(df))) # disciplinary self-efficacy (chemistry)
MSochem <- subset(df, select=c(scale, grep("MSochem", colnames(df)))) # disciplinary growth mindset (organic chemistry)
IPochem <- subset(df, select=grep("IPochem", colnames(df))) # instructor growth mindset (organic chemistry)
SEochem <- subset(df, select=grep("SEochem", colnames(df))) # disciplinary self-efficacy (organic chemistry)
CNEBochem_class <- cbind.data.frame(subset(subset(df, select=grep("CNEBochem", colnames(df))), select=c(1:3))) # entity norms and beliefs
CNEBochem_self <- cbind.data.frame(subset(subset(df, select=grep("CNEBochem", colnames(df))), select=c(4:6))) # entity norms and beliefs
CNHSochem_others <- cbind.data.frame(subset(subset(df, select=grep("CNHSochem", colnames(df))), select=c(1:3))) # help seeking
CNHSochem_self <- cbind.data.frame(subset(subset(df, select=grep("CNHSochem", colnames(df))), select=c(4:6))) # help seeking
CNSWochem <- subset(df, select=grep("CNSWochem", colnames(df))) # help seeking
FCochem <- subset(df, select=grep("FCochem", colnames(df))) # faculty caring

IDochem$FASochem03_rc[IDochem$FASochem03 == 1] <- 4
IDochem$FASochem03_rc[IDochem$FASochem03 == 2] <- 3
IDochem$FASochem03_rc[IDochem$FASochem03 == 3] <- 2
IDochem$FASochem03_rc[IDochem$FASochem03 == 4] <- 1
IDochem$FASochem03 <- IDochem$FASochem03_rc
IDochem <- subset(IDochem, select=-c(FASochem03_rc))

Identity

Items

  1. I see myself as a [chemistry kind of person]
  2. My parents see me as a [chemistry kind of person]
  3. My instructors see me as a [chemistry kind of person]
  4. My friends see me as a [chemistry kind of person]
  5. My peers see me as a [chemistry kind of person]
  6. I have had experiences in which I was recognized as a [chemistry kind of person]
  7. Knowing chemistry is important for (1=no jobs; 2=a few jobs; 3=most jobs; 4=all jobs)
  8. Knowing chemistry helps me understand how the world works. (1=never; 2=sometimes; 3=most of the time; 4=all of the time)
  9. Thinking like a chemist will help me do well in (1=none of my classes; 2=a few of my classes; 3=most of my classes; 4=all of my classes)
  10. Chemistry makes the world a better place to live
  11. I look forward to my [chemistry] classes.
  12. I don’t care about learning chemistry.
  13. In general, I find [chemistry] (1=very boring; 2=boring; 3=interesting; 4=very interesting)

Stats - Original

Univariate Stats

d <- subset(IDochem, scale == "orig", select=-c(scale, IDochem01))
IDochem_desc <- data.frame(describe(d))
datatable(subset(IDochem_desc, select=-c(n, trimmed, mad))) %>%
  formatRound(1:10) %>%
  formatStyle(8:9, color = styleInterval(c(-2, 2), c('red', 'black', 'red')))

Missingness

vis_miss(d)

# gg_miss_upset(EEochem)

Histograms

ggplot(gather(d), aes(value)) + 
  geom_histogram(bins = 4) + 
  facet_wrap(~key)

Warning Removed 13 rows containing non-finite values (stat_bin).

Item Correlations

corr <- corr.test(d, adjust = "holm")

rval <- corr$r
rval[lower.tri(corr$r, diag = T)] <- NA

datatable(rval) %>%
  formatRound(1:ncol(rval)) %>%
  formatStyle(1:ncol(rval), color = styleInterval(c(-.7, .7), c('red', 'black', 'red')))
corrplot(corr$r)

EFA (2fac)

d <- na.omit(d)
ev <- eigen(cor(d))
ap <- parallel(subject=nrow(d),var=ncol(d),rep=100,cent=.05)
nS <- nScree(x=ev$values, aparallel=ap$eigen$qevpea)
plotnScree(nS)

EFA <- factanal(d, factors = 2, rotation = "promax", cutoff = 0.3)
print(EFA, digits=3, cutoff=.4, sort=TRUE)
## 
## Call:
## factanal(x = d, factors = 2, rotation = "promax", cutoff = 0.3)
## 
## Uniquenesses:
##  IDochem02  IDochem03  IDochem04  IDochem05  IDochem06  IDochem10  IDochem07 
##      0.467      0.624      0.194      0.121      0.558      0.809      0.904 
##  IDochem08  IDochem09 FASochem02 FASochem03 FASochem05 
##      0.675      0.625      0.431      0.455      0.268 
## 
## Loadings:
##            Factor1 Factor2
## IDochem02   0.741         
## IDochem04   0.878         
## IDochem05   0.924         
## IDochem06   0.619         
## IDochem08           0.654 
## IDochem09           0.604 
## FASochem02          0.628 
## FASochem03          0.670 
## FASochem05          0.745 
## IDochem03                 
## IDochem10                 
## IDochem07                 
## 
##                Factor1 Factor2
## SS loadings      2.975   2.581
## Proportion Var   0.248   0.215
## Cumulative Var   0.248   0.463
## 
## Factor Correlations:
##         Factor1 Factor2
## Factor1   1.000  -0.492
## Factor2  -0.492   1.000
## 
## Test of the hypothesis that 2 factors are sufficient.
## The chi square statistic is 60.29 on 43 degrees of freedom.
## The p-value is 0.0418

EFA (3fac)

d <- na.omit(d)
ev <- eigen(cor(d))
ap <- parallel(subject=nrow(d),var=ncol(d),rep=100,cent=.05)
nS <- nScree(x=ev$values, aparallel=ap$eigen$qevpea)
plotnScree(nS)

EFA <- factanal(d, factors = 3, rotation = "promax", cutoff = 0.3)
print(EFA, digits=3, cutoff=.4, sort=TRUE)
## 
## Call:
## factanal(x = d, factors = 3, rotation = "promax", cutoff = 0.3)
## 
## Uniquenesses:
##  IDochem02  IDochem03  IDochem04  IDochem05  IDochem06  IDochem10  IDochem07 
##      0.458      0.585      0.194      0.120      0.558      0.493      0.888 
##  IDochem08  IDochem09 FASochem02 FASochem03 FASochem05 
##      0.618      0.585      0.446      0.498      0.005 
## 
## Loadings:
##            Factor1 Factor2 Factor3
## IDochem02   0.768                 
## IDochem04   0.885                 
## IDochem05   0.942                 
## IDochem06   0.639                 
## FASochem03          0.545         
## FASochem05          1.123         
## IDochem10          -0.404   0.904 
## IDochem08                   0.621 
## IDochem03                         
## IDochem07                         
## IDochem09                         
## FASochem02          0.406         
## 
##                Factor1 Factor2 Factor3
## SS loadings      3.044   2.048   1.715
## Proportion Var   0.254   0.171   0.143
## Cumulative Var   0.254   0.424   0.567
## 
## Factor Correlations:
##         Factor1 Factor2 Factor3
## Factor1   1.000   0.553   0.734
## Factor2   0.553   1.000   0.447
## Factor3   0.734   0.447   1.000
## 
## Test of the hypothesis that 3 factors are sufficient.
## The chi square statistic is 39.06 on 33 degrees of freedom.
## The p-value is 0.216

Stats - Alternative

Univariate Stats

d <- subset(IDochem, scale == "alt", select=-c(scale, IDochem01))
IDochem_desc <- data.frame(describe(d))
datatable(subset(IDochem_desc, select=-c(n, trimmed, mad))) %>%
  formatRound(1:10) %>%
  formatStyle(8:9, color = styleInterval(c(-2, 2), c('red', 'black', 'red')))

Missingness

vis_miss(d)

# gg_miss_upset(EEochem)

Histograms

ggplot(gather(d), aes(value)) + 
  geom_histogram(bins = 4) + 
  facet_wrap(~key)

Warning Removed 34 rows containing non-finite values (stat_bin).

Item Correlations

corr <- corr.test(d, adjust = "holm")

rval <- corr$r
rval[lower.tri(corr$r, diag = T)] <- NA

datatable(rval) %>%
  formatRound(1:ncol(rval)) %>%
  formatStyle(1:ncol(rval), color = styleInterval(c(-.7, .7), c('red', 'black', 'red')))
corrplot(corr$r)

EFA (2fac)

d <- na.omit(d)
ev <- eigen(cor(d))
ap <- parallel(subject=nrow(d),var=ncol(d),rep=100,cent=.05)
nS <- nScree(x=ev$values, aparallel=ap$eigen$qevpea)
plotnScree(nS)

EFA <- factanal(d, factors = 2, rotation = "promax", cutoff = 0.3)
print(EFA, digits=3, cutoff=.4, sort=TRUE)
## 
## Call:
## factanal(x = d, factors = 2, rotation = "promax", cutoff = 0.3)
## 
## Uniquenesses:
##  IDochem02  IDochem03  IDochem04  IDochem05  IDochem06  IDochem10  IDochem07 
##      0.178      0.393      0.095      0.103      0.500      0.553      0.870 
##  IDochem08  IDochem09 FASochem02 FASochem03 FASochem05 
##      0.760      0.586      0.317      0.362      0.285 
## 
## Loadings:
##            Factor1 Factor2
## IDochem02   0.919         
## IDochem03   0.673         
## IDochem04   0.916         
## IDochem05   0.903         
## IDochem06   0.743         
## IDochem10           0.666 
## IDochem09           0.555 
## FASochem02          0.741 
## FASochem03          0.850 
## FASochem05          0.820 
## IDochem07           0.421 
## IDochem08           0.485 
## 
##                Factor1 Factor2
## SS loadings      3.557   3.141
## Proportion Var   0.296   0.262
## Cumulative Var   0.296   0.558
## 
## Factor Correlations:
##         Factor1 Factor2
## Factor1   1.000  -0.649
## Factor2  -0.649   1.000
## 
## Test of the hypothesis that 2 factors are sufficient.
## The chi square statistic is 76.65 on 43 degrees of freedom.
## The p-value is 0.00121

EFA (3fac)

d <- na.omit(d)
ev <- eigen(cor(d))
ap <- parallel(subject=nrow(d),var=ncol(d),rep=100,cent=.05)
nS <- nScree(x=ev$values, aparallel=ap$eigen$qevpea)
plotnScree(nS)

EFA <- factanal(d, factors = 3, rotation = "promax", cutoff = 0.3)
print(EFA, digits=3, cutoff=.4, sort=TRUE)
## 
## Call:
## factanal(x = d, factors = 3, rotation = "promax", cutoff = 0.3)
## 
## Uniquenesses:
##  IDochem02  IDochem03  IDochem04  IDochem05  IDochem06  IDochem10  IDochem07 
##      0.178      0.370      0.092      0.104      0.498      0.552      0.553 
##  IDochem08  IDochem09 FASochem02 FASochem03 FASochem05 
##      0.440      0.346      0.203      0.362      0.315 
## 
## Loadings:
##            Factor1 Factor2 Factor3
## IDochem02   0.916                 
## IDochem03   0.654                 
## IDochem04   0.927                 
## IDochem05   0.910                 
## IDochem06   0.753                 
## IDochem10           0.625         
## FASochem02          0.917         
## FASochem03          0.825         
## FASochem05          0.702         
## IDochem07                   0.737 
## IDochem08                   0.756 
## IDochem09                   0.665 
## 
##                Factor1 Factor2 Factor3
## SS loadings      3.563   2.502   1.626
## Proportion Var   0.297   0.208   0.135
## Cumulative Var   0.297   0.505   0.641
## 
## Factor Correlations:
##         Factor1 Factor2 Factor3
## Factor1   1.000  -0.658   0.402
## Factor2  -0.658   1.000  -0.551
## Factor3   0.402  -0.551   1.000
## 
## Test of the hypothesis that 3 factors are sufficient.
## The chi square statistic is 23.89 on 33 degrees of freedom.
## The p-value is 0.877

1PL Model - Orig (All)

Summary & Fit

d <- subset(IDochem, scale == "orig", select=-c(scale, IDochem01))
d <- d %>%
  mutate_at(vars(1:ncol(d)), recode, `1` = 0, `2` = 0, `3` = 1, `4` = 1)

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -525.1756 1076.351 1107.479
## 
## Coefficients:
##                     value std.err  z.vals
## Dffclt.IDochem02   0.0564  0.2039  0.2767
## Dffclt.IDochem03   0.5225  0.2128  2.4558
## Dffclt.IDochem04  -0.1259  0.2054 -0.6130
## Dffclt.IDochem05   0.0417  0.2050  0.2034
## Dffclt.IDochem06  -0.2637  0.2082 -1.2665
## Dffclt.IDochem10  -1.3689  0.2795 -4.8981
## Dffclt.IDochem07   1.1811  0.2531  4.6669
## Dffclt.IDochem08   0.1933  0.2047  0.9445
## Dffclt.IDochem09   0.2854  0.2061  1.3850
## Dffclt.FASochem02  0.0563  0.2039  0.2761
## Dffclt.FASochem03 -0.8617  0.2367 -3.6399
## Dffclt.FASochem05 -0.8615  0.2367 -3.6394
## Dscrmn             1.5802  0.1862  8.4861
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.0068 
## quasi-Newton: BFGS
item.fit(mod, simulate.p.value=T)
## 
## Item-Fit Statistics and P-values
## 
## Call:
## rasch(data = d)
## 
## Alternative: Items do not fit the model
## Ability Categories: 10
## Monte Carlo samples: 100 
## 
##                X^2 Pr(>X^2)
## IDochem02   6.3754   0.6634
## IDochem03  10.2568   0.2673
## IDochem04   3.4484   0.9307
## IDochem05   6.0347   0.6832
## IDochem06   2.7277   0.9703
## IDochem10   7.8934   0.3762
## IDochem07  10.9962   0.2277
## IDochem08   6.6592   0.5941
## IDochem09   7.1053   0.6436
## FASochem02  4.7206   0.9505
## FASochem03  4.7346   0.8416
## FASochem05  2.9827   0.9604

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0))

1PL Model - Orig (1F)

Summary & Fit

d1 <- subset(d, select=c(IDochem02, IDochem04, IDochem05, IDochem06))
d2 <- subset(d, select=c(IDochem08, IDochem09, FASochem03, FASochem05, FASochem02))

d <- d1

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##   log.Lik      AIC      BIC
##  -179.118 368.2361 380.2083
## 
## Coefficients:
##                    value std.err  z.vals
## Dffclt.IDochem02  0.0284  0.1699  0.1669
## Dffclt.IDochem04 -0.1225  0.1711 -0.7160
## Dffclt.IDochem05  0.0063  0.1710  0.0367
## Dffclt.IDochem06 -0.2363  0.1733 -1.3636
## Dscrmn            2.6389  0.4499  5.8660
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.0017 
## quasi-Newton: BFGS
# item.fit(mod, simulate.p.value=T)

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

All Items IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0), ylim=c(0,20))

1PL Model - Orig (2F)

Summary & Fit

d <- d2

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -228.2363 468.4726 482.8393
## 
## Coefficients:
##                     value std.err  z.vals
## Dffclt.IDochem08   0.1778  0.1909  0.9312
## Dffclt.IDochem09   0.2633  0.1925  1.3678
## Dffclt.FASochem03 -0.8072  0.2190 -3.6852
## Dffclt.FASochem05 -0.8073  0.2191 -3.6853
## Dffclt.FASochem02  0.0505  0.1897  0.2660
## Dscrmn             1.8634  0.2978  6.2579
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.00033 
## quasi-Newton: BFGS
# item.fit(mod, simulate.p.value=T)

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

All Items IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0), ylim=c(0,20))

1PL Model - Alt (All)

Summary & Fit

d <- subset(IDochem, scale == "alt", select=-c(scale, IDochem01))
d <- d %>%
  mutate_at(vars(1:ncol(d)), recode, `1` = 0, `2` = 0, `3` = 1, `4` = 1)

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -673.7889 1373.578 1407.702
## 
## Coefficients:
##                     value std.err  z.vals
## Dffclt.IDochem02   0.1093  0.2026  0.5391
## Dffclt.IDochem03   0.4013  0.2067  1.9412
## Dffclt.IDochem04  -0.0146  0.2025 -0.0720
## Dffclt.IDochem05   0.1505  0.2029  0.7419
## Dffclt.IDochem06  -0.1801  0.2039 -0.8836
## Dffclt.IDochem10  -1.0851  0.2400 -4.5209
## Dffclt.IDochem07   1.2615  0.2487  5.0730
## Dffclt.IDochem08   0.7680  0.2183  3.5179
## Dffclt.IDochem09   0.7553  0.2186  3.4547
## Dffclt.FASochem02  0.3591  0.2058  1.7451
## Dffclt.FASochem03  0.7973  0.2208  3.6110
## Dffclt.FASochem05 -1.0869  0.2400 -4.5287
## Dscrmn             1.3400  0.1396  9.5977
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.0036 
## quasi-Newton: BFGS
item.fit(mod, simulate.p.value=T)
## 
## Item-Fit Statistics and P-values
## 
## Call:
## rasch(data = d)
## 
## Alternative: Items do not fit the model
## Ability Categories: 10
## Monte Carlo samples: 100 
## 
##                 X^2 Pr(>X^2)
## IDochem02   18.8455   0.0099
## IDochem03    8.7749   0.4257
## IDochem04   22.4626   0.0099
## IDochem05   26.4120   0.0099
## IDochem06    8.5436   0.3762
## IDochem10    4.4591   0.9109
## IDochem07    4.2467    0.901
## IDochem08   13.8865   0.0792
## IDochem09   14.2048   0.0693
## FASochem02   6.4658   0.7129
## FASochem03 109.1016   0.0099
## FASochem05   8.7083   0.4752

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0))

1PL Model - Alt (1F)

Summary & Fit

d1 <- subset(d, select=c(IDochem02, IDochem03, IDochem04, IDochem05, IDochem06))
d2 <- subset(d, select=c(FASochem03, FASochem05, FASochem02))
d3 <- subset(d, select=c(IDochem07, IDochem08, IDochem09))

d <- d1

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -230.7766 473.5532 489.3031
## 
## Coefficients:
##                   value std.err z.vals
## Dffclt.IDochem02 0.2085  0.1198 1.7401
## Dffclt.IDochem03 0.4087  0.1142 3.5801
## Dffclt.IDochem04 0.1237  0.1229 1.0064
## Dffclt.IDochem05 0.2370  0.1190 1.9911
## Dffclt.IDochem06 0.0111  0.1295 0.0853
## Dscrmn           3.9512  0.6530 6.0511
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.00021 
## quasi-Newton: BFGS
item.fit(mod, simulate.p.value=T)

Warning in rasch(data = X.new): Hessian matrix at convergence is not positive definite; unstable solution.

## 
## Item-Fit Statistics and P-values
## 
## Call:
## rasch(data = d)
## 
## Alternative: Items do not fit the model
## Ability Categories: 10
## Monte Carlo samples: 100 
## 
##               X^2 Pr(>X^2)
## IDochem02  4.5007   0.5149
## IDochem03 14.1437   0.0594
## IDochem04  4.3800   0.3861
## IDochem05  6.1705   0.2277
## IDochem06 22.3728   0.0198

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

All Items IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0), ylim=c(0,20))

1PL Model - Alt (2F)

Summary & Fit

d <- d2

mod <- rasch(d)

Warning in rasch(d): Hessian matrix at convergence is not positive definite; unstable solution.

summary(mod)

Warning in sqrt(diag(new.covar)): NaNs produced

Warning in sqrt(diag(new.covar)): NaNs produced

Warning in sqrt(diag(new.covar)): NaNs produced

Warning in sqrt(Var[n.ind + 1, n.ind + 1]): NaNs produced

## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -184.7279 377.4558 387.9557
## 
## Coefficients:
##                      value std.err z.vals
## Dffclt.FASochem03  12.8236     NaN    NaN
## Dffclt.FASochem05 -16.9410     NaN    NaN
## Dffclt.FASochem02   5.7263     NaN    NaN
## Dscrmn              0.0601     NaN    NaN
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 1.6 
## quasi-Newton: BFGS
# item.fit(mod, simulate.p.value=T)

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

All Items IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0), ylim=c(0,20))

1PL Model - Alt (3F)

Summary & Fit

d <- d3

mod <- rasch(d)
summary(mod)
## 
## Call:
## rasch(data = d)
## 
## Model Summary:
##    log.Lik      AIC      BIC
##  -157.0437 322.0874 332.5873
## 
## Coefficients:
##                   value std.err z.vals
## Dffclt.IDochem07 0.9615  0.1937 4.9635
## Dffclt.IDochem08 0.5788  0.1691 3.4221
## Dffclt.IDochem09 0.5513  0.1689 3.2640
## Dscrmn           2.3354  0.4559 5.1227
## 
## Integration:
## method: Gauss-Hermite
## quadrature points: 21 
## 
## Optimization:
## Convergence: 0 
## max(|grad|): 0.0023 
## quasi-Newton: BFGS
item.fit(mod, simulate.p.value=T)
## 
## Item-Fit Statistics and P-values
## 
## Call:
## rasch(data = d)
## 
## Alternative: Items do not fit the model
## Ability Categories: 10
## Monte Carlo samples: 100 
## 
##              X^2 Pr(>X^2)
## IDochem07 7.7303   0.5644
## IDochem08 9.0927   0.4554
## IDochem09 9.0279   0.6436

ICC

plot(mod, type="ICC", cex = .7, legend = F, col = 1)

All Items IIC

plot(mod, type="IIC", cex = .7, legend = F, col = 1)

Individual ICC Plots

items <- colnames(d)
n <- 1
for (i in 1:ncol(d)) {
  plot(mod, type = 'ICC', auto.key = FALSE, items = n, main = items[n], annot = F)
  n <- n + 1
}

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Warning in plot.window(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy, type, …): “auto.key” is not a graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in axis(side = side, at = at, labels = labels, …): “auto.key” is not a

graphical parameter

Warning in box(…): “auto.key” is not a graphical parameter

Warning in title(…): “auto.key” is not a graphical parameter

Warning in plot.xy(xy.coords(x, y), type = type, …): “auto.key” is not a

graphical parameter

Test Information Function

plot(mod, type=c("IIC"), items=c(0), ylim=c(0,20))