„CTT“ package
Simona Galbavá (459829)
Kateřina Kožmínová (460195)

disattenuated.cor()
•korekce proti zeslabení nereliabilitou
•disattenuated.cor(r.xy,c(r.xx,r.yy))
•# r.xy=0.6, r.xx=0.7,r.yy=0.8
•disattenuated.cor(0.6,c(0.7,0.8))
•          [,1]
•[1,] 0.8017837

spearman.brown()
•spearman.brown(r.xx, input = 2, n.or.r = "n")
•
•#old reliability is 0.82, if we want a new measure to be 0.9, the new test length is
•> spearman.brown(0.82, input = 0.9, n.or.r = "r")
•$`n.new`
•[1] 1.97561
•
•#old reliability is 0.82, if the measure is shortened to half length, the reliability of new test
is
•> spearman.brown(0.82, input = 0.5, n.or.r = "n")
•$`r.new`
•[1] 0.6949153

splitHalf()
•„psych“ package
•> splitHalf(ODdata)
•Split half reliabilities
•Call: splitHalf(r = ODdata)
•
•Maximum split half reliability (lambda 4) =  0.9
•Guttman lambda 6  =  0.86
•Average split half reliability =  0.82
•Guttman lambda 3 (alpha) =  0.82
•Minimum split half reliability  (beta) =  0.58
•Average interitem r =  0.2  with median =  0.18

lowerCor()
•„psych“ package
•

alpha()
•„psych“ package
•alpha(data, check.keys =T)
•std.alpha – méně zkreslený odhad
•   (zešikmené položky, různé škály)
•

Další funkce - psych
•EFA_model <- fa(ODdata, nfactors = 2, rotate = "oblimin")
•EFA_model$loadings
•Faktorové náboje položek
•fa.diagram(EFA_model)
•Path diagrams
•describe(ODdata)
•Statistiky položek
•AUC(c(TP,FP,FN,TN))
•Specificita, senzitivita
•
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