1 of 5

Given a data set that can be graphed as a standard normal curve, respond to the prompts below. (1 point each)

1. What defines the graph? I.e., what determines the shape of the graph and what is the relationship between these defining characteristics?
2. What must be done in order to transform a normal distribution of data into a standard normal distribution based on the same data?
3. What is the advantage of having transformed data so that it can be represented by a standard normal distribution?
4. We often see data points represented by either x or z. What is the relationship between them?
5. Why is the area under the standard normal curve above the mean always the same value?

2 of 5

A school psychologist wants to determine whether children who live with both parents perform better on school work than children who live with a single parent. She gathers two groups for her comparison, 20 children who live with both parents and another 20 who live with a single parent. The psychologist plans to use scores on a standardized achievement test as an indicator of school performance. Respond to the prompts below. (1 point each)

1. What statistical test would be appropriate in this case? Explain the rationale for your answer.
2. Identify the independent variable in this study.
3. Identify the dependent variable in this study.
4. Describe a potentially confounding variable and explain how that might affect the conclusions from the study.
5. State the null and alternative hypotheses in words.

3 of 5

A social worker notes that in a population of psychiatric inpatients the ethnic mix seems out of balance with what she has understood to be the ratios in the general population. Respond to the prompts below to show how she might determine whether the inpatient ethnic mix varies from the mix in the general population. (1 point each)

1. What statistical test would be appropriate to use here? Explain the rationale for your answer.
2. What assumptions would need to be met in order to use the test?
3. Describe the data that the test would be based on as either quantitative or qualitative. Explain the rationale for your answer.
4. Write an example of how the null and alternative hypotheses for this test could be stated.
5. What would the researcher need to know in order to calculate the appropriate test statistic? I.e., what values need to be known or calculated in order to complete the calculation of the test statistic?

4 of 5

A team of psychologists have developed an experimental treatment program for a learning disorder with the expectation that the treatment would enable recipients to score higher than before on a test of learning ability. To test the treatment, they randomly select a pool of 30 volunteers who have been diagnosed with the disorder and who have volunteered for the treatment program. Following treatment, the participants are retested on the learning ability test and their scores compared to earlier scores. Complete the following. (1 point each)

1. What statistical test would be appropriate in this case? Explain the rationale for your answer.
2. State the null and alternative hypotheses in words.
3. State the null and alternative hypotheses in statistical symbols
4. Would the test be right-tailed, left-tailed or two-tailed? Explain the rationale for your answer.
5. Describe a potentially confounding variable and explain how that might affect the conclusions from the study.Describe a potentially confounding variable and explain how that might affect the conclusions from the study.

5 of 5

A social psychology professor is interested in determining whether cell phone use while driving is related to having received a speeding violation. Complete the following. (1 point each)

1. What statistical test would be appropriate to use? Explain the rationale for your answer.
2. Suggest how levels of these variables might be arranged in a table.
3. Write an example of how the null and alternative hypotheses for this test could be stated.
4. Is the statistical test right-tailed, left-tailed or two-tailed? Explain the rationale for your answer.
5. Assuming a statistically significant outcome, write a statement summarizing the conclusion.