a. Calculate samepl mean, X = Sum of Xi / n = 69/18 = 3.83 b. Sample standard de

Question

a. Calculate samepl mean, X = Sum of Xi / n = 69/18 = 3.83

b. Sample standard deviation, S = ((Xi - X)2/(n-1)) = 2.79

c. Standard error of the mean, SX = S/n = 2.79/18 = 0.658

d. The Null hypothesis of the research is that there is no significance difference between the sample mean (mean time of first job) and the population mean. so we are interested to find out the deviation from mean in either direction. Hence, it is a two tailed test.

e. Degree of freedom = n-1 = 18-1 = 17

f. For 95% confidence level, we need to locate critical t-value corresponding to 1-(1-)/2 = 1-(1-.95)/2 = t0.975

In the t-distribution table, look for df = 17, and t0.975 , critical t-value = 2.110

g. t-distribution critical value = (X - 0)/SX = (3.83-0)/0.658 = 5.82

Computed t value is greater than critical t-value, therefore, we H0 is not rejected.

h. and i is the same question. 95% confidence interval is calculated below

Lower limit = X - t*SX = 3.83 - 2.11*0.658 = 2.44

Upper limit = X + t*SX = 3.83 + 2.11*0.658 = 5.22

j. in this case, t value = (3.82-2)/0.658 = 2.78

t value is still more than critical t-value, therefore null hypothesis would be accepted.

Explanation / Answer

INSTRUCTIONS: TO RECEIVE FULL CREDIT FOR THIS EXTRA CREDIT OPPORTUNITY YOU MUST SHOW ALL WORK AND CALCULATIONS NECESSARY TO ANSWER THE RESEARCH QUESTION (10 Pts) A group of local businesspersons is interested is finding out how long newly hired UTEP business graduates remain in their first jobs. The group wants to estimate the population mean time on the first job with 95 % confidence. A random sample of subjects was taken: 3,4,7,1,12,1, 2,2,5 4, 2,3,1, 3,4,2,6,7 Number of Years on First Job You know that the confidence interval estimate of the population mean for this sample is: where u population mean = sample mean t = Critical Value of t @ 95 % S = Standard Error of the Mean S = Sample Standard Deviation n = sample size Upper Limit = X+ tSz Lower Limit = X- tSq Or The following steps are required to answer the research question: Calculate the sample mean, X Estimate the population standard deviation by calculating S the sample standard deviation. a. b. (n 1) Estimate the Standard Error of the Mean (S) Is the hypothesis or research question one or two tailed? Calculate the degrees of freedom Determine the critical t-values associated with the 95 % confidence level from the t Distribution table. Given the above, what is the t distribution critical value? Calculate the lower and upper limits of the confidence interval. What is the confidence interval @ 95 % for the mean number of years spent on the first job? If the group had estimated the mean number of years spend on the first job to be two (2) years, would the hypothesis be accepted or rejected. Explain your answer. c. d. e. f. g. h. i. j.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.