1. A researcher suspected that the number of between-meal snacks eaten by students in a day during final examinations might depend on the number of tests that a student had to take on that day. The following table shows joint probabilities, estimated from a survey. Number of Number of Tests (X) Snacks (Y) 1 3 0.07 0.09 0.06 0.01 1 0.07 0.06 0.07 0.01 2 0.06 0.07 0.14 0.03 0.02 0.04 0.16 0.04 a. Find the mean number of tests taken by students on that day. b. Find the mean number of snacks eaten by students on that day. c. Find and interpret the conditional probability function of Y, given that X = 3. d. Find the covariance between X and Y. e. Are the number of snacks and number of tests independent of each other?

1. A researcher suspected that the number of between-meal snacks eaten by students in a day during final examinations might depend on the number of tests that a student had to take on that day. The following table shows joint probabilities, estimated from a survey. Number of Number of Tests (X) Snacks (Y) 1 3 0.07 0.09 0.06 0.01 1 0.07 0.06 0.07 0.01 2 0.06 0.07 0.14 0.03 0.02 0.04 0.16 0.04 a. Find the mean number of tests taken by students on that day. b. Find the mean number of snacks eaten by students on that day. c. Find and interpret the conditional probability function of Y, given that X = 3. d. Find the covariance between X and Y. e. Are the number of snacks and number of tests independent of each other?

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Description: 1. A researcher suspected that the number of between-meal snacks eaten by students in a day during finalexaminations might depend on the number of tests that a student had to take on that day. The following tableshows joint probabilities, estimated

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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