Question

You manage Human Relations for your company. One of your sales managers has retired, leaving an opening. You are considering two different employees for the position. Both are highly qualified so you have decided to evaluate their sales performance for the past year.

Use the Week 4 Data Set to create and calculate the following in Excel^®:

Determine the range of values in which you would expect to find the average weekly sales for the entire sales force in your company 90% of the time.

Calculate the impact of increasing the confidence level to 95%?

Calculate the impact of increasing the sample size to 150, assuming the same mean and standard deviation, but allowing the confidence level to remain at 90%?   

Based on the calculated confidence interval for weekly sales on the sample of 50 reps at a 90% confidence level:

Calculate both Reps' average weekly performance and highlight if it is greater than the population mean.

You want to determine whether there is a statistically different average weekly sales between Sales Rep A and Sales Rep B.

Create Null and Alternative Hypothesis statements that would allow you to determine whether their sales performance is statistically different or not.

Use a significance level of .05 to conduct a t-test of independent samples to compare the average weekly sales of the two candidates.

Calculate the p-value?

Considering that individual you did not promote:

Determine whether this person's average weekly sales are greater than the average weekly sales for the 50 sales reps whose data you used to develop confidence intervals.

Create Null and Alternative Hypothesis statements that would allow you to determine whether the new Sales Manager's weekly average sales are greater than the sample of Sales Reps.

Use a significance level of .05 to conduct a t-test of independent samples to compare the average weekly sales of both.

Calculate the p-value?

SAMPLE OF WEEKLY SALES
Sales Rep  #	AverageWeekly Sales($)		Week #	Weekly Sales($) - Rep A	Weekly Sales($) - Rep B
1	1228		1	4657	5839
2	7374		2	6133	2602
3	1055		3	3438	2830
4	1859		4	7394	4763
5	3938		5	4327	3740
6	1692		6	2552	2315
7	569		7	7063	1599
8	4059		8	7844	1629
9	3689		9	6898	2416
10	607		10	4003	2107
11	1370		11	6884	4237
12	3735		12	4007	6322
13	3305		13	7214	3710
14	7228		14	2358	5890
15	6279		15	7745	5119
16	1671		16	1337	5184
17	5708		17	1052	3439
18	2569		18	6056	4828
19	4163		19	1495	3667
20	1519		20	3530	3518
21	7734		21	4749	6073
22	784		22	3833	5566
23	6766		23	7869	4555
24	7261		24	4541	5867
25	5034		25	6882	6039
26	7115		26	3868	1032
27	6291		27	5934	4834
28	6287		28	4447	3687
29	2080		29	5504	5500
30	7621		30	5554	4659
31	1047
32	6517
33	5172
34	3876
35	5429
36	4538
37	3786
38	2510
39	4863
40	7246
41	1175
42	641
43	4269
44	7034
45	3406
46	2256
47	3182
48	5178
49	4428
50	1189

Answer 1

Please see the excel screenshots below

Determine the range of values in which you would expect to find the average weekly sales for the entire sales force in your company 90% of the time.

as can be seen from the calculation , the range with 90% confidence is 3440.59, 4492.68

Calculate the impact of increasing the confidence level to 95%?

as we increase the confidence level confidence onterval increases
3339.85 , 4593.42  

Calculate the impact of increasing the sample size to 150, assuming the same mean and standard deviation, but allowing the confidence level to remain at 90%?

when we increase the sample size , the confidence interval reduces when compared to sample size 50

3662.92 , 4270.35

Based on the calculated confidence interval for weekly sales on the sample of 50 reps at a 90% confidence level:
Calculate both Reps' average weekly performance and highlight if it is greater than the population mean.

we see that the mean value of repb is less than that of rep a and hence is more close to the overall population mean of 3966.64

Please note that we can answer only 4 subparts of the question at a time as per the answering guidelines