AP PSYCHOLOGY

Detailed explanation-1: -In 1904, Charles Spearman had developed a statistical procedure called factor analysis. In factor analysis, related variables are tested for correlation to each other, then the correlation of the related items are evaluated to find clusters or groups of the variables.

Detailed explanation-2: -Factor analysis is a statistical test that is used to find relationships between multiple correlated measures and Spearman played a clear part in its development. Spearman coined the term factor analysis and used it extensively in analyzing multiple measures of cognitive performance.

Detailed explanation-3: -Spearman developed rank correlation (1904) and the widely used correction for attenuation (1907). His statistical work was not appreciated by his University College colleague Karl Pearson and there was a long feud between them.

Detailed explanation-4: -L.L. Thurstone, considered the father of factor analysis, uses 60 terms across 1300 subjects to arrive at five broad factors.

Detailed explanation-5: -Factor analysis began with psychologist Charles Spearman around a century ago. He noticed the huge variety of measures for cognitive acuity-visuo-spatial skill, artistic abilities, reasoning etc.-and wondered if one general, underlying intelligence variable (which he called g) could explain them all.