Week Six Homework Exercise

Answer the following questions, covering material from Ch. 12 of Methods in Behavioral

Research:

1. Define the following terms:

 Descriptive statistics

 Scales of measurement

 Measures of central tendency

 Frequency distributions

 Correlation coefficient

 Effect size

 Multiple regression

1. How are group means, percentages, and correlations used to describe research results?

1. How can graphs be used to describe and summarize data?

1. A researcher is studying reading rates in milliseconds per syllable. What scale of

measurement—nominal, ordinal, interval, or ratio—is time in milliseconds? Explain your

response.

1. Under what circumstances is the median or mode a better measure of central tendency than

1. True or false: The standard deviation and the range are sensitive to outliers. Explain your

response.

1. True or false: The standard deviation can never be 0. Explain your response.

1. A researcher is investigating the effects of anxiety on creativity. Individuals with varying levels

of anxiety are asked to complete a measure of creativity. The results show a classic U-

shaped distribution; that is, individuals with moderate levels of anxiety score the highest on

tests of creativity. Individuals with very low or very high levels of anxiety score much lower on

tests of creativity. What would be a good statistic to use in this case? Explain your response.

1. What are some applications of multiple regression models (equations / techniques)? Provide

an example.

1. Explain how and why multiple correlations are used as prediction variables?