In: Statistics and Probability
Company ABC | Company XYZ |
18,42280727 | 18,11722091 |
23,25971383 | 18,03236506 |
24,47267508 | 11,70181582 |
16,43125944 | 28,6349246 |
24,28843419 | 20,01970193 |
28,94755272 | 21,43805892 |
23,99634997 | 25,77991841 |
21,24041049 | 17,61727736 |
13,03788468 | 23,17141939 |
22,48407401 | 19,44828346 |
11,75437848 | 16,47678806 |
25,32910531 | 27,07743766 |
28,29293481 | 22,60188244 |
18,07510972 | 21,75405717 |
18,52644874 | 17,69497663 |
27,387692 | 17,85126192 |
31,33021511 | 26,10624511 |
17,54311671 | 21,061494 |
19,60308128 | 20,38612598 |
24,13955445 | 23,3838603 |
22,91021548 | 27,90996637 |
24,93664016 | 15,98477416 |
17,39909368 | 15,16035132 |
23,66404789 | 21,78663413 |
26,33621608 | 25,21042693 |
34,52750735 | 25,72431418 |
28,47319212 | 22,36474307 |
20,53729378 | 21,05484901 |
21,29081923 | 20,54825477 |
14,71201432 | 16,49442088 |
24,47566959 | 15,64039399 |
14,28379238 | 18,38440203 |
12,40888724 | 23,25464953 |
18,93436393 | 18,26911221 |
29,47781996 | 18,64149345 |
22,68654117 | 25,70740895 |
22,51631105 | 20,85214458 |
24,03909167 | 23,93770199 |
31,76300726 | |
17,96011776 | |
28,38274287 | |
17,65424787 | |
27,28002602 | |
22,83645773 | |
23,3062072 | |
15,58564764 | |
25,03221213 | |
20,24033921 | |
26,41886186 | |
18,33414518 |
A large consumer electronics retailer is planning to expand its
e-commerce operations. To this end, the management is considering
establishing a strategic partnership with courier company XYZ for
the delivery of customers’ orders.
Question 1
The management of the retailer is prepared to proceed with the
partnership only if XYZ can deliver orders faster than company ABC
that is currently used by the retailer. The e-commerce department
of the retailer has collected data from 50 random orders delivered
by ABC in the last two months and 38 similar random orders
delivered by XYZ in the same period. The data is included in the
table below and refer to the time (in hours) between the placement
of each order and the delivery to the customer. Use an appropriate
statistical test to advise the management of the retailer whether
or not they should partner with XYZ.
Two-Sample T-Test and CI: Company XYZ, Company ABC
Method
μ₁: mean of Company XYZ |
µ₂: mean of Company ABC |
Difference: μ₁ - µ₂ |
Equal variances are not assumed for this analysis.
Descriptive Statistics
Sample | N | Mean | StDev | SE Mean |
Company XYZ | 38 | 1914772030 | 634053480 | 102857057 |
Company ABC | 50 | 2137753853 | 662544963 | 93698007 |
Estimation for Difference
Difference | 95% Upper Bound for Difference |
-222981824 | 8524712 |
Test
Null hypothesis | H₀: μ₁ - µ₂ = 0 |
Alternative hypothesis | H₁: μ₁ - µ₂ < 0 |
Null hypothesis H₀: μ₁ - µ₂ = 0
Alternative hypothesis H₁: μ₁ - µ₂ < 0 ( XYZ company is delivering faster than ABC company)
test statistic t =
df =
T-Value | DF | P-Value |
-1.60 | 81 | 0.056 |
Since p-value is more than alpha 0.05 we fail to reject H0 and there is no sufficient evidence to conclude that XYZ company is delivering faster than ABC company. Hence the management of the retailer should not partner with XYZ.