A basketball coach believes that the variance of the heights of adult male basketball players is different from the variance of heights for the general population of men. The sample variance of heights, measured in inches, for a random sample of 19 basketball players is 14.22. The sample variance for a random sample of 18 other men is 34.49. Assume that both population distributions are approximately normal and test the coach’s claim using a 0.10 level of significance. Does the evidence support the coach’s claim? Let male basketball players be Population 1 and men in general be Population 2.   Step 1 of 3:  State the null and alternative hypotheses for the test. Fill in the blank below. H0: σ21=σ22: Ha: σ21⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯σ22 Step 2 of 3:  Compute the value of the test statistic. Round your answer to four decimal places. Step 3 of 3:  Draw a conclusion and interpret the decision.

You work for a soft-drink company in the quality control division. You are interested in the variance of one of your production lines as a measure of consistency. The product is intended to have a mean of 12 ounces, and your team would like the variance to be as low as possible. You gather a random sample of 16 containers. Estimate the population variance at a 80% level of confidence. 11.82 11.83 11.85 11.89 11.9 11.97 12 12 12 12.01 12.02 12.04 12.05 12.11 12.16 12.18 Variance of Data: 0.012 Note: Round all values to 3 decimals and use those rounded values in subsequent calculations. a) Find the lower and upper x critical values at 80% confidence: Lower: Upper: b) Report your confidence interval for o?: Lower Bound: Upper Bound:

A sample of 76 female workers and another sample of 48 male workers from a state produced mean weekly earnings of $743.50 for the females and $777.63 for the males. Suppose that the population standard deviations of the weekly earnings are $80.05 for the females and $88.68 for the males. The null hypothesis is that the mean weekly earnings are the same for females and males, while the alternative hypothesis is that the mean weekly earnings for females is less than the mean weekly earnings for males. Directions: • Label your answers with the correct statistical symbols. • If you use the Ti, identify which function and values you used to calculate. If you solve by hand, show all steps 2.5 The significance level for the test is 1%. What is/are the critical value(s)? 2.6. What is the value of the test statistic, rounded to three decimal places? 2.7. What is the p-value for this test, rounded to four decimal places? 2. 8. Using the p-value approach, do you reject or fail to reject the null…

The accounting department analyzes the variance of the weekly unit costs reported by two production departments. A sample of 16 cost reports for each of the two departments shows cost variances of 2.3 and 5.4, respectively. Is this sample sufficient to conclude that the two production departments differ in terms of unit cost variance? Use  ? = 0.10. State the null and alternative hypotheses. -H0: ?12 > ?22 Ha: ?12 ≤ ?22 -H0: ?12 ≠ ?22 Ha: ?12 = ?22      -H0: ?12 ≤ ?22 Ha: ?12 > ?22 -H0: ?12 = ?22 Ha: ?12 ≠ ?22 Find the value of the test statistic. (Round your answer to two decimal places.) statistic=?? Find the p-value. (Round your answer to four decimal places. Remember: When using WebAssign technology to find p-values, use the entire test statistic (not the rounded answer from the previous question.)) p-value = ??   State your conclusion. -Reject H0. We can conclude that there is a difference between the population variances. -Do not reject H0. We cannot conclude that…

Scientists measured the amount of drug in tablets produced at two different, independent sites. Scientists want to know whether there is any difference between the mean drug concentration in tablets produced at Site 1 and Site 2. Run the appropriate test in Excel, assuming the population variances are equal. Use an a = .05 significance level. Submit the...

In a study of birth order and intelligence, IQ tests were given to 18- and 19-year-old men to estimate the size of the difference, if any, between the mean IQs of firstborn sons and secondborn sons. The following data for 10 firstborn sons and 10 secondborn sons are consistent with the means and standard deviations reported in the article. It is reasonable to assume that the samples come from populations that are approximately normal. Can you conclude that the mean IQ of firstborn sons is greater than the mean IQ of secondborn sons? Let μ1 denote the mean IQ of firstborn sons and μ2 denote the mean IQ of secondborn sons. Use the α = 0.01 level and the P-value method with the table. Firstborn 128 101 128 112 121 105 122 98 106 108 Secondborn 121 125 110 107 114 93 80 94 91 83 Part(a): State the appropriate null and alternate hypotheses. H0:   H1: This is a _____…