A 5-year study among 601 participants with retinitis pigmentosa assessed the effects of high-dose vitamin A (15,000 IUper day) and vitamin E (400 IU per day) on the course of their disease. One issue is to what extent supplementation withvitamin A affected their serum-retinol levels. The test used to analyze the effects of vitamins assumes that the distributionof serum retinol is approximately normal. To verify this assumption, the investigators obtained a frequency distribution ofserum retinol at year O among males in the vitamin A group, with data as shown in the table below. The mean serumretinol for the group was 1.89 and the standard deviation was 0.36.nSerum-retinolgroup(μmol/L)≤1.40561.405-1.755221.755-2.105222.105-2.45520≥2.45531. Perform a statistical test to check on the normality assumption. Given your results, do you feel the assumption ofnormality is warranted? Why or why not?

Serum retinoln< = 1.40561.405 to 1.755221.755 to 2.105222.105 to 2.45520 = 2.455"}"…

Answered: A 5-year study among 601 participants…

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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