The paper is concerned with the measurement of internal consistency of rating scales and interviewing schedules, with the assessment of bias between different raters and with coefficients for measuring the degree of agreement between them. Analysis of variance models are first employed, but reference is also made to earlier psychometric techniques and to recent work by Armitage et al. and by Fleiss.

No abstract

Summary The younger sibs of a random sample of 11‐year‐old Scottish children were tested individually as they reached the age of 11 years. The average intelligence of the younger sibs is found to be lower than that of the random sample, and explanations of this difference are discussed. It is shown, however, that if one ‘average’ sib is taken for each subject, then the mean score of these ‘sibs’ is not significantly different from that of their subjects. Some implications for the selection of samples of sibs are examined, together with the effect of incomplete families on the estimation of the relationship between intelligence test score and size of sibship. Different methods of ascertaining the correlation for i.q. among sibs are discussed, and the results presented. The correlation coefficient for I.Q. between sibs is found to be of the order of r =+ 0.5.

Tests Children Error The British Journal of Psychology, March, Statistical Section 1952 fNJ,I, = ST say Hl + HPt Dlz = So say 9 D I P = S, say