1.The mean change in muscle thickness observed after a 4-week training regimen was 4 mm, and the 95% confidence interval (CI) for mean change was (-0.5, 8.5). Which is the best scientific conclusion for the effectiveness of this regimen?

An increase in 4 mm is impressive, so the regimen has been proven effective.

Although a mean increase was observed, it is not statistically significant because the 95% CI includes zero change.

The lower limit of the CI is less than zero, which means a new person undergoing this training can be expected to lose muscle thickness.

The upper limit of the CI is greater than 8, which means that an increase of 8 mm is our best prediction for a new person undergoing this training.

2.The distribution of systolic blood pressure (SBP)tends to be symmetric and bell-shaped for adults between the ages of 45-55.An investigator wishes to calculate a 95% confidence interval (CI) for mean SBP based on a sample of n=20 adults in this age range.Which of the following is the most appropriate formula for the upper limit of the 95% CI?

sample mean+2.09*SEM

sample mean+2.18*SEM

sample mean-1.99*SEM

sample mean+1.96*SEM

3.

An education organization claims that the mean SAT scores for male athletes and male non-athletes at a college are different. A random sample of 26 male athletes at the college has a mean SAT score of 1783 and a standard deviation of 218. A random sample of 18 male non-athletes at the college has a mean SAT score of 2064 and a standard deviation of 186. Which test would best be used to compare SAT scores between these groups?

A one sample Z test for sample proportions

A two sample Z test for sample proportions

A two sample t test for sample means

A one sample t test for sample means

4.

A medical research team studied the number of head and neck injuries sustained by hockey players. Of the 319 players who wore a full-face shield, 195 sustained an injury. Of the 323 players who wore a half-face shield, 204 sustained an injury. Which statistical test would be most appropriate to compare the protective benefits of full vs half-face shields?

A one sample Z test for sample proportions

A two sample Z test for sample proportions

A two sample t test for sample means

A one sample t test for sample means

5.

True or False? If there are outliers, then the mean will always be greater than the median.

True

False

6.

The central limit theorem (CLT) guarantees that any sample proportion is approximately normally distributed.

True

False

7.True or false? Even with small sample sizes (e.g. 15 people), the sampling distribution will always be exactly normally distributed

True

False

8.True or False? The probability of a Z score being less than 0 is 84%.

True

False

9.True or False? Sampling distributions are created assuming a fixed sample size, n.

True

False

10.Given that a population is normally distributed with a mean of 100 and a standard deviation of 8, determine the Z score of X = 88

+1.5

12

-1.5

99.5