Читать книгу Elementary Regression Modeling - Roger A. Wojtkiewicz - Страница 31

Although the unit of analysis in quantitative social science research is often an individual, the analytical unit is a group of individuals. The basic analytical approach in social science research is to describe differences between groups. Measurement involves assigning a characteristic or a value of a variable to a unit of analysis. Measurements can range from simply names as in the nominal level, to ordered names as in the ordinal level, and then to meaningful numerical values as in the interval level.

Researchers can count the number of particular values for nominal, ordinal, and interval variables in a group, while also summing up interval variables. The mean compares a sum of a variable relative to the sample size N, whereas proportions and percentages compare counts of a particular value of a variable relative to sample size N. Alternative measures involving counts are the odds that compares the count for one value of a variable with the count for a second value of a variable. The log odds is the natural logarithm of the odds. Researchers compare groups by taking the difference in means or log odds. Analyzing differences is a key task in social science research.