Introductory Statistics

 

IS: R Assignment 15

[<code class="R">R</code> Assignments]
R Assignment #15

 

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 8, 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 calculate quantiles associated with the Normal distribution (a.k.a. the Gaussian distribution). Again, it may be helpful for you to review the All Probabilities handout.


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


The Problems

There is no data to load, because we are working with probability distributions today. So, please answer the following questions.

  1. What value of x is the 10th percentile of the X ~ N(μ=2; σ=3) distribution?
  2. What value of x is the 90th percentile of the X ~ N(μ=2; σ=3) distribution?
  3. What value of x separates the lower 30% from the upper 70%, when X ~ N(μ=2; σ=3)?

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:

qnorm(0.10, m=2,s=3)
qnorm(0.90, m=2,s=3)
qnorm(0.30, m=2,s=3)

The answers are

-1.844655
5.844655
0.4267985

When writing out numbers, remember that e translates to — and should be written as — “times 10 to the power of.”

This page was last modified on 2 January 2024.
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