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Table for Determining phi Coefficients

Published online by Cambridge University Press:  01 January 2025

C. E. Jurgensen
C. E. Jurgensen*
Affiliation:
Minneapolis Gas Light Company
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Abstract

A table is presented which directly gives phi coefficients accurate to three places when entered by the proportion of one sub-group responding in a specified manner and the proportion of a second sub-group responding in the same manner. The table gives coefficients identical with those obtained by formula if the sub-groups are equal in number. The phi coefficients can readily be expressed, if desired, in terms of critical ratio or chi square. The table is more accurate than the use of abacs and eliminates the use of time-consuming formulas. Accurate determination of item validity on the basis of statistically rigorous techniques can be made more quickly by means of the table than validity determined by less efficient methods which have previously been used to save time.

Type
Original Paper
Information
Psychometrika , Volume 12 , Issue 1 , March 1947 , pp. 17 - 29
Copyright
Copyright © 1947 The Psychometric Society

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