CCJS 300 Lecture Notes - Lecture 10: United States Parole Commission, Chi-Squared Test, Semantic Differential

• School: University of Maryland
• Department: Criminology and Criminal Justice
• Course: CCJS 300
• Professor: Alan Lehman

Document Summary

Levels of measurement: all variables may be classified as belonging to a particular level of measurement. Nominal: categorical, mutually exclusive categories, t-test or chi square test used when assuming an iv. Ordinal: may rank order the variable responses, numbers imply some distance (i. e. attitude scales, spearman rank, order correlation) Interval: equal intervals between values of a variable (i. e. temperature scale, iq tests) Ratio: true zero-point, equal distances between, advanced techniques such as correlation and regression used. Scaling procedures: using more than one question to measure something. May be hard if we just use one question. Scales & indices are efficient for data analyses. Useful in our understanding of measurement in general. The mean is an efficient measure of central tendency. Index: constructed through accumulation of scores on individual attributes (similar to a checklist) Scale: assignment of scores to patterns of attributes, may have an intensity structure. Use interval or ratio level variables if possible.