: Which of the following scatterplot(s) would have a correlation coefficient that is close to 0? (Select all that apply.) View
: Which of the following scatterplot(s) would fitting a linear regression model to the data be appropriate? (Select all that apply.) View
: A 95% confidence interval for the mean brain weight for all adults in 1905 with a head size of 3400 cm3 was calculated to be (1210.14 grams, 1232.33 grams). How would the width of the 95% confidence interval for the mean brain weight for all adults in 1905 with a head size of 3600 cm3 compare to this one? View
: The study relating brain weight (grams) and head size (cubic cm) yielded an R-squared of 0.6393. Which of the following is a correct interpretation of the R-squared? View
: Suppose that the migraine researcher was also interested in pain score trends immediately following administration of the drug. The researcher continues to collect pain score measurements at four, six, and eight hours after administration of either the experimental drug or the placebo pill. View
: A researcher at a large pharmaceutical company wishes to study the effect of a new experimental drug on the amount of pain suffered by people who frequently experience migraines. The researcher conducts a randomized experiment, View
: After performing the analysis, the researcher writes a press release describing the results of the experiment, and claims that the new experimental drug will reduce pain by 25% based on the results of the modeling. View
: The figure below presents the fits of four different regression models to the same set of data, where there is a predictor variable (x) and a dependent variable (y) of interest. Which of the four plots reflects a model that fits the data well? View