Inconnect Question 13 0 pts Does taking Vitamin D increase the mean lifespan of
ID: 3220956 • Letter: I
Question
Inconnect Question 13 0 pts Does taking Vitamin D increase the mean lifespan of a rat? A sample of 20 rats was randomized to group 1 (control and group 2 Vitamin D). The lifespan (days) of each rat was measured. Here is some of the output. Means and Std Deviations Std Err Number Mean Std Dev Mean Lower 95% Upper 95% 10 531.500 83.3350 26.353 471.89 591.11 10 611-S00 88.2563 27,909 S48.37 674.63 Which of the following is correct? The standard errors estimate how much the average lifetime for each group could vary if new samples of 10 rats were taken. The standard errors are only an estimate not a measure for the variation in the averages for groups of 10 rats. Because 10 rats were randomized to each of the two groups, a matched pairs design could be used. About 95% of rats in group 1 have lifetimes between 470 days and 590 days. Because the two standard deviations are about equal, there is no evidence that the average lifetimes are different. This is incorrect. The standard deviations provide no information about the comparison of means. Text reference: section 18.2.Explanation / Answer
For question 13
option a is the right answer
The standard error (SE) is the standard deviation of the sampling distribution of a statistic, most commonly of the mean. The term may also be used to refer to an estimate of that standard deviation, derived from a particular sample used to compute the estimate.