As part of a staged rollout, a new email client was installed on some of the computers of a major company's customer service representatives (CSRs). One of the company's performance analysts has been tasked with estimating the difference on the busiest day of the year between the mean time (in minutes) spent working on email for CSRS using the new email client and the mean time (in minutes) spent working on email for CSRS using the old email client. On the busiest day of the year, the performance analyst studies a random sample of 17 CSRS using the new email client and a random sample of 18 CSRS using the old email client. (These samples are chosen independently.) The analyst records the amount of time (in minutes) each CSR spends working on email. These data are shown in the table. Times working on email (in minutes) New email client 172, 198, 178, 178, 170, 173, 170, 195, 172, 172, 187, 213, 169, 179, 185, 175, 180 Old email client 214, 270, 144, 215, 93, 150, 128, 168, 178, 252, 144, 107, 81, 98, 111, 159, 149, 210 Send data to calc... ✓ Assume that the two populations of times are approximately normally distributed. Let u, be the population mean time spent working on email by CSRS using the new client. Let μ₂ be the population mean time spent working on email by CSRS using the old client. Construct a 90% confidence interval for the difference μ₁-₂. Then find the lower and upper limit of the 90% confidence interval. Carry your intermediate computations to three or more decimal places. Round your answers to two or more decimal places. (If necessary, consult a list of formulas.) Lower limit: Upper limit: X
As part of a staged rollout, a new email client was installed on some of the computers of a major company's customer service representatives (CSRs). One of the company's performance analysts has been tasked with estimating the difference on the busiest day of the year between the mean time (in minutes) spent working on email for CSRS using the new email client and the mean time (in minutes) spent working on email for CSRS using the old email client. On the busiest day of the year, the performance analyst studies a random sample of 17 CSRS using the new email client and a random sample of 18 CSRS using the old email client. (These samples are chosen independently.) The analyst records the amount of time (in minutes) each CSR spends working on email. These data are shown in the table. Times working on email (in minutes) New email client 172, 198, 178, 178, 170, 173, 170, 195, 172, 172, 187, 213, 169, 179, 185, 175, 180 Old email client 214, 270, 144, 215, 93, 150, 128, 168, 178, 252, 144, 107, 81, 98, 111, 159, 149, 210 Send data to calc... ✓ Assume that the two populations of times are approximately normally distributed. Let u, be the population mean time spent working on email by CSRS using the new client. Let μ₂ be the population mean time spent working on email by CSRS using the old client. Construct a 90% confidence interval for the difference μ₁-₂. Then find the lower and upper limit of the 90% confidence interval. Carry your intermediate computations to three or more decimal places. Round your answers to two or more decimal places. (If necessary, consult a list of formulas.) Lower limit: Upper limit: X
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
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Transcribed Image Text:As part of a staged rollout, a new email client was installed on some of the computers of a major company's customer
service representatives (CSRs). One of the company's performance analysts has been tasked with estimating the difference
on the busiest day of the year between the mean time (in minutes) spent working on email for CSRS using the new email
client and the mean time (in minutes) spent working on email for CSRS using the old email client.
On the busiest day of the year, the performance analyst studies a random sample of 17 CSRS using the new email client and
a random sample of 18 CSRS using the old email client. (These samples are chosen independently.) The analyst records the
amount of time (in minutes) each CSR spends working on email. These data are shown in the table.
Times working on email (in minutes)
New email client 172, 198, 178, 178, 170, 173, 170, 195, 172, 172, 187, 213, 169, 179, 185, 175, 180
Old email client 214, 270, 144, 215, 93, 150, 128, 168, 178, 252, 144, 107, 81, 98, 111, 159, 149, 210
Send data to calc... v
Assume that the two populations of times are approximately normally distributed. Let µ₁ be the population mean time spent
working on email by CSRS using the new client. Let ₂ be the population mean time spent working on email by CSRs using
the old client.
Construct a 90% confidence interval for the difference µ₁¯µ₂. Then find the lower and upper limit of the 90% confidence
interval. Carry your intermediate computations to three or more decimal places. Round your answers to two or more decimal
places. (If necessary, consult a list of formulas.)
Lower limit:
Upper limit:
►
W
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