What z-score value separates 30% of the distribution in the tail on the left (i.e., the bottom 30% of the distribution) from the rest of the distribution ? z=

Which BEST describes the shape of the distribution?            Uniform       Skewed right       Skewed left       Symmetrical

What proportion of the distribution of sample means is between a z  of 1.34 and z of -1.00?

What does the P-value describe?

6

a. Use a = 0.10 to test for a statistically significantly difference between the population means for first- and fourth-round scores. What is the p-value? t-value (to 3 decimals) Degrees of freedom p-value is greater than 0.20 What is your conclusion? There is no significant difference between the mean scores for the first and final rounds. b. What is the point estimate of the difference between the two population means? (to 2 decimals) For which round is the population mean score lower? First round c. What is the margin of error for a 90% confidence interval estimate for the difference between the population means? (to 3 decimals) Could this confidence interval have been used to test the hypothesis in part (a)? Yes Explain. Use the point of the difference between the two population means and add and subtract this MOE. If zero is in the interval the difference is not statistically significant. If zero is not in the interval the difference is statistically significant.

True or false- The interquartile range is the distance between the lowest score and in the middle 50% of the distribution, and the highest score in the middle 50% of the distribution.

The F-statistic is a ratio score resulting in a measure of the estimated proportion of variance due to the independent variable. True or false

Use the sample statistics to test the claim that the mean score on a final exam is more than 78. x¯=81x¯=81 s=10s=10 n=41