Question

A researcher wants to know whether supplements affect how long vampires can go without requiring human blood. She took one sample of vampires (n = 10). Half received a placebo first and the supplement second, while the other half received the sup- plement first and the placebo second. She then recorded how many days the vampires could go without consuming human blood for each condition. The goal of the study was to see whether there would be any difference between supplement and placebo. Conduct the appropriate t-test for these data (α = 0.05) and calculate a confidence interval (95%) as a measure of effect size. Assume all assumptions for the test are met. (See table below for sample data.)

Given all of this informations, the researchers obtained a t test statistic of tobtained = −2.08. They also found an effect size of a 95% CI[−9.39, 0.39].

1. What kind of t-test was this? Independent-samples or repeated-measures?

2. Write the hypotheses for this kind of t-test.

3. Given the data shown, state the correct conclusion. (You’ll have to find your critical region first.)

4. Write an interpretation of the findings. Make sure that your conclusion paragraph includes all the important statistics: your t, df, alpha, and effect size, as well as the individual group means. Also make sure that you include a plain English statement at the end.

Answer 1