FAQ/criteria - CBU statistics Wiki

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Describe FAQ/criteria here. For 2 x 2 tables there are four terms used to summarise the classification table of observed and predicted group membership outputted by discriminant procedures such as binary logistic regression.

Let’s call the two groups positive (+) and negative (-) then

The following four quantities are often quoted and asked for by journals as a means of evaluating the sharpness of the model fit in the two group case.

1-tail

2-tail

correlation

Kendall

Spearman

Pearson

Kendall

Spearman

Pearson

True

+

-

Pred

+

a

b

||||||||<25% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> || - || c || d || Sensitivity = a/(a+c)= proportion of those who are really + who test +

Specificity = d/(b+d) = proportion of those who are really - who test -

PPV = a/(a+b) = proportion of those who tested + who really are +

NPV = d/(c+d) = proportion of those who tested - who really are -