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.

# How Do We Estimate Central Tendency and Variation in Categorical and Ordinal Variables?

### How Do We Estimate Central Tendency and Variation in Categorical and Ordinal Variables?

We use a frequency procedure to estimate central tendency and variation for categorical and ordinal variables. A frequency distribution provides a lot of information. For instance, a frequency distribution lists all possible values of the variables alongside the count and percentage of the sample that falls into that value. Table 74.1 provides an example of a frequency. Note that there are 565 respondents in the sample (n = 565).

The frequency distribution tells us that there are 396 white respondents in the sample, which comes to 70% (point estimate) of the total sample. This is the modal category. The mode is defined as the most frequently occurring value. In this sample, ...