A researcher decides to study if having a pet leads to lower levels of anxiety. She...
A researcher decides to study if having a pet leads to lower levels of anxiety. She collects data from a sample of dog owners (n=30) and measures their anxiety levels, which range between 0 and 100. She finds a mean level of anxiety of 68 with a standard deviation of 5. This researcher knows that the mean anxiety level of the population is 60, and wants to compare it to this sample.
Calculate the 95% confidence interval for this test (One-Sample t-Test).
Homework Answers
We know that the 95% confidence interval for population mean in this case is given by:
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A researcher decides to study if having a pet leads to lower
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