Under the old method of postoperative treatment, the mean length of patients' hospital stay was 7.2days. A new method of postoperative treatment was evaluated for patients undergoing a certain surgicalprocedure. 165 patients are recruited, and they all received the new method. The sample mean for thenew method was 6.9 days, and the standard deviation was 0.24 days.a. The researcher who propose the new method says that since the mean days using the new method isless than 7.2, the new method is better. Explain why this reasoning is incorrect.b. The new method would be used if it can shorten the length of hospital stay. State the appropriatenull and alternate hypothesis determine whether the new method should be used.c. Compute the P-value. Would you recommend using the new method? Explain.

It is given that: The sample size, n=165 The sample average duration (in days) of stay by the new…

Answered: Under the old method of postoperative…

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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