KEY FEATURES: Introduces students to developing research questions and shows their importance in driving research design. Rarely taught topics, such as how to enter and clean data, offer students information missed in both research methods and statistics courses. Shows how to write up survey results for academic, business and nonprofit reports to alleviate the confusion students feel about how to write up findings. Rigorous treatment of sampling focuses on many sampling issues from probability theory to weighting. Offers the process of actually conducting a survey with advice on administering surveys, incentives, and improving response rates.

# What Are Variables?

### What Are Variables?

A variable is derived directly from each survey question. It varies from person to person within the survey, which is why it is called a variable. There are three basic types of variables: continuous (ratio and interval), ordinal, and nominal (see Q40). If a survey question asks about family income, then the variable, faminc, will consist of the dollar amount of income for each respondent. Family income is an example of a continuous variable. That is, the response categories are not fixed by the survey itself and can take on any positive number with up to two decimal places. Continuous variables lend themselves really well to mathematical operations.

Variables are measured as dichotomous and nominal if there are two response categories. ...