Assume a Researcher Found That the Correlation Between a Test

question 22

Multiple Choice

Assume a researcher found that the correlation between a test she had developed and exam performance was .5 in a study of 25 students. She had previously been informed that correlations under .30 are considered unacceptable. The 95% confidence interval was [0.131, 0.747]. Can you be confident that the true correlation is at least 0.30?

• A)Yes you can, because the correlation coefficient is .5 (which is above .30) and falls within the boundaries of the confidence interval.
• B)No you cannot, because the lower boundary of the confidence interval is .131, which is less than .30, and so the true correlation could be less than .30.
• C)Yes you can, because the upper boundary of the confidence interval is above .30 we can be 95% confident that the true correlation will be above .30
• D)No you cannot, because the sample size was too small.

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Definitions:

Bulimia

An eating disorder characterized by binge eating followed by purging, through methods such as vomiting or excessive exercise, to prevent weight gain.

Relapse

A return to previous behavior or condition, often used to describe the recurrence of substance use or the worsening of psychological symptoms after a period of improvement.

Food Diary

A tool for tracking what, when, and how much one eats, often used to monitor eating habits for weight loss or to identify food intolerances.

Bulimia

An eating disorder characterized by episodes of binge eating followed by behaviors such as vomiting or excessive exercise to prevent weight gain.