Introductory Statistics

[cal] [docs] [modules] [eBook]
 

IS: R Assignment 25

[<code class="R">R</code> Assignments]
R Assignment #25
 

General Purpose

General Purpose of these Assignments (the usual): The purpose of these R Assignments is to give you some pointed, direct practice in using R. As such, these are designed to be quick and to the point (less than 10 minutes each). They are also designed to give you a place to return if you forget how to perform some analysis in the future.

Please supply your results in the form below. Clicking on “Click to Check Your Answers” will allow you to see which as correct and which are not. When all are correct (and you can try as many time as you wish), you will be allowed to send your answers to me for credit by clicking on “Click to Email Your Results.” You only receive credit when this is submitted (with all answers correct).

This assignment is due at the start of the class period on

Thursday, February 22, 2024.

With that being said, if this R Assignment is available, which is could be until approximately 11:59 pm (CST), then you are able to work on it.

As expected, these are graded according to the syllabus (all or nothing). Please review the appropriate section in the syllabus for more information. Also, if this is not submitted before it is due, then it counts as a zero.

Specific Purpose: Here, I check that you can perform a Chi-square goodness-of-fit test.

Slidedeck Support: The following slidedeck may be helpful for you in completing this R Assignment:

The Problems

Note that we are assuming this particular experiment is representative of the entire population (all people). The sample is of 500 people. On each person I measured the eye color and the hair color.

First, run the following code. Then, answer the questions that follow. These lines of code load a particular data set and attaches it. In other words, they allow you easy access to a common data set.

source("http://rfs.kvasaheim.com/stat200.R") dt = read.csv("http://rfs.kvasaheim.com/data/hairandeyecolor.csv") attach(dt)
  1. Test the hypothesis that the proportion of blue-eyed and brown-eyed people are equal. Just report the p-value. (Hint: Use the Binomial test and only these two categories.)
  2. Test the hypothesis that the eye color and hair color are independent. (Hint: The answer is 0.2926.)
  3. Test the hypothesis that the proportions of blue, brown, and “other” eye colored people is 40%, 40%, and 20%. Just report the p-value.

Finally, to receive credit for this assignment, please provide your full Knox College email address:

then click on the button here.

The Answers

Since this is past due, I can now give you the code and the answer:

Since it is now after the time this is due, I can now give you the code and the answers:

binom.test(x=187, n=410)
chisq.test( table(eye,hair) )
chisq.test( table(eye), p=c(0.40,0.40,0.20) )

The answers are

0.08377
0.2926
0.1059
This page was last modified on 2 January 2024.
All rights reserved by Ole J. Forsberg, PhD, ©2008–2024. No reproduction of any of this material is allowed without explicit written permission of the copyright holder.