STA 311 STATISTICS in SAS Instructions Provide SAS

STA 311 - STATISTICS in SAS

Instructions • • Provide SAS code for each problem in a Word document. Insert your SAS Code first. Then provide all relevant output from SAS into your word document with your respective interpretation of the output for the problem being analyzed. Any data set referred by a problem is on D 2 L in the. zip file. Problems without data sets you are required to get the data into SAS. You must complete all items within a problem. All results must be interpreted. Remember Statistics is a communications course. Each person must do his/her own work. Do not work together. Do not discuss with each other. Any form of cheating will be handled case-by-case. Alpha level is 0. 05 unless specified in the problem. Solutions must be organized and legible. Note: Provided sample means and sample standard deviations are approximate (symbol @ mean “about” or “approximate”).

Question 1 • An educator claims that the average salary of substitute teachers in school districts of Allegheny County, PA, is less than $60 per day. A random sample of 8 schools is selected and the daily salaries are shown: • $60, $56, $60, $55, $70, $55, $60, $55. • State the population. • State what case this is and which SAS program you plan to use. • State the Null hypothesis and Alternative (be clear if it is a one-sided or two-sided test). • Perform the test for alpha = 0. 05 and interpret the results • Perform the test for alpha = 0. 10 and interpret the results. • Create a 90% confidence interval around the sample mean salary.

Question 2 • A medical researcher wishes to see whether the pulse rate for smokers and nonsmokers is no different. A sample of 100 nonsmokers and 100 smokers are acquired. Smokers had a sample mean of @ 92. 1 and sample standard deviation of @ 15. 9. Non-smokers had a sample mean of @ 86. 5 and sample standard deviation of @ 11. 4. Can the researcher conclude , at alpha =0. 01, that there is no difference in pulse rates. • Refer to the data set SMOKE. • State the population. • State what case this is and which SAS program you will use. • State the Null and Alternative hypothesis. • Conduct and interpret the analysis. • State the p-value and the Confidence Interval for the Difference.

Question 3 • • • Two manufacturing companies produce carbide drill tips that are used to cut holes in steel sheets. A customer wishing to know which drill tips have the longer life purchases independent samples of n 1=20 drill tips from Company 1 and n 2=15 drill tips for Company 2. The mean lives of the drill tips are approximately 76. 3 minutes and 83. 6 minutes, respectively. The sample variances for the drill tips are approximately 40. 1 and 15. 6 respectively. Assume alpha=0. 05 Refer to the DRILL data set. State the null and alternative hypothesis. What is the main issue prior to conducting this analysis and what are you going to do to address this issue? Which case is this? State the results of the test.

Question 4 • An educator claims that the average salary of substitute teachers in school districts of Allegheny County, PA, is less than the average salary of substitute teachers in Montgomery County, PA. A random sample of 8 schools per county are selected and the daily salaries are shown: • Allegheny: $60, $56, $60, $55, $70, $55, $60, $55. • Montgomery: $72, $68, $54, $58, $55, $83, $79, $49 • State the Null hypothesis and Alternative. • Perform the test for alpha = 0. 05 and interpret the results • What case is this?