The following data represent the length of time, in days, to recovery for patients randomly treated with one of two medications to clear up severe bladder infections Find a 95% confidence interval for the difference p,-H, between in the mean recovery times for the two medications, assuming normal populations with equal variances. Medication 1 s =17 s3-13 n = 13 X1 = 14 Medication 2 n2 = 17 X2 = 18 The confidence interval is <µ,-< (Round to two decimal places as needed.) Enter your answer in the edit fields and then click Check Answer All parts showing Clear All Fal Cherk

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
100%
### Confidence Interval Analysis

The following data represent the length of time, in days, to recovery for patients randomly treated with one of two medications to clear up severe bladder infections. We need to find a 95% confidence interval for the difference \(\mu_2 - \mu_1\) between the mean recovery times for the two medications, assuming normal populations with equal variances.

#### Data Summary:
| Medication | \( n \) (Sample Size) | \( \overline{x} \) (Sample Mean) | \( s^2 \) (Sample Variance) |
|------------|-----------------------|---------------------------------|----------------------------|
| Medication 1 | \( n_1 = 13 \)         | \( \overline{x}_1 = 14 \)        | \( s_1^2 = 1.7 \)           |
| Medication 2 | \( n_2 = 17 \)         | \( \overline{x}_2 = 18 \)        | \( s_2^2 = 1.3 \)           |

#### Confidence Interval Formula:
The formula for the confidence interval for the difference between two means (\(\mu_2 - \mu_1\)) with equal variances is given by:

\[ \left( \overline{x}_2 - \overline{x}_1 \right) \pm t_{\alpha/2, \, df} \cdot \sqrt{ \left( \frac{(n_1 - 1)s_1^2 + (n_2 - 1)s_2^2}{n_1 + n_2 - 2} \right) \left( \frac{1}{n_1} + \frac{1}{n_2} \right) } \]

#### Calculations:
- Calculate the pooled variance:
  \[ s_p^2 = \frac{(n_1 - 1)s_1^2 + (n_2 - 1)s_2^2}{n_1 + n_2 - 2} \]
  
- Insert the sample values:
  \[ s_p^2 = \frac{(13 - 1) \cdot 1.7 + (17 - 1) \cdot 1.3}{13 + 17 - 2} = \frac{12 \cdot 1.7 + 16 \cd
Transcribed Image Text:### Confidence Interval Analysis The following data represent the length of time, in days, to recovery for patients randomly treated with one of two medications to clear up severe bladder infections. We need to find a 95% confidence interval for the difference \(\mu_2 - \mu_1\) between the mean recovery times for the two medications, assuming normal populations with equal variances. #### Data Summary: | Medication | \( n \) (Sample Size) | \( \overline{x} \) (Sample Mean) | \( s^2 \) (Sample Variance) | |------------|-----------------------|---------------------------------|----------------------------| | Medication 1 | \( n_1 = 13 \) | \( \overline{x}_1 = 14 \) | \( s_1^2 = 1.7 \) | | Medication 2 | \( n_2 = 17 \) | \( \overline{x}_2 = 18 \) | \( s_2^2 = 1.3 \) | #### Confidence Interval Formula: The formula for the confidence interval for the difference between two means (\(\mu_2 - \mu_1\)) with equal variances is given by: \[ \left( \overline{x}_2 - \overline{x}_1 \right) \pm t_{\alpha/2, \, df} \cdot \sqrt{ \left( \frac{(n_1 - 1)s_1^2 + (n_2 - 1)s_2^2}{n_1 + n_2 - 2} \right) \left( \frac{1}{n_1} + \frac{1}{n_2} \right) } \] #### Calculations: - Calculate the pooled variance: \[ s_p^2 = \frac{(n_1 - 1)s_1^2 + (n_2 - 1)s_2^2}{n_1 + n_2 - 2} \] - Insert the sample values: \[ s_p^2 = \frac{(13 - 1) \cdot 1.7 + (17 - 1) \cdot 1.3}{13 + 17 - 2} = \frac{12 \cdot 1.7 + 16 \cd
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 2 images

Blurred answer
Knowledge Booster
Point Estimation, Limit Theorems, Approximations, and Bounds
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman