Psychology Chapter 2 -- Psychological Research Methods & Statistics

The value of a case study is that ____.

• it provides an intensive study of a person or group and can prove or disprove a hypothesis

• the researchers' conclusions are generally correct

• it provides results that can be generalized for other applications

• it provides a wealth of descriptive material that may generate new hypotheses

Which of the following statements about surveys is NOT TRUE?

• Surveys are the most practical way to gather data on large numbers of people.

• Surveys consist of interviews, questionnaires, or a combination of the two.

• Interviews take less time to administer than questionnaires, and the results are more uniform.

• Questionnaires prevent the researcher's mannerisms from influencing the participant's answers.

Two commonly used measures of variance are ____.

• range and standard deviation

• mode and median

• range and mean

• standard deviation and median

All of the following statements about measures of variance are true EXCEPT ____.

• On an aptitude test, if the highest score is 50 and the lowest is 20, the range is 30.

• Because the standard deviation uses only a small amount of information, it is considered a crude measure of variance.

• Standard deviation is similar to the "average" distance of every score to the mean of the scores.

• The larger the standard deviation from the mean score, the more spread out the scores are.

Which of the following statements about correlation coefficients is TRUE?

• A correlation coefficient provides an index of the spread of the scores of a distribution.

• A positive correlation indicates that as one variable increases, the second variable decreases.

• A scatter plot demonstrates the direction of the relationship between two variables.

• A correlation coefficient describes the balance point of distribution.

A researcher wants to know whether failure at a task causes aggression. As part of her study, some subjects are told they have failed at a task, whereas others are told they have succeeded. Failing or not at the tasks would be

• placebo

• the independent variable

• a within-subjects manipulation

• the dependent variable

• a counterbalance procedure