Hypothesis Test

A WebQuest for Math 153 (Introduction to Statistical Methods )

Designed by

Donna Hiestand-Tupper
dtupper@ccbcmd.edu

 hyptest.jpg (10823 bytes)

Introduction | Task | Process | Evaluation | Conclusion | Back to Lecture



Introduction

In a package of any type of M&M, the M&M Mars company claims there is a certain percentage of each color.  For example, in a package of peanut M&M's, 12% are brown, 12% are red, 15% are yellow, 23% are blue, 15% are green and 23% are orange.

In a recently purchased pack of peanut M&M's, 9 of the 65 peanut M&M's were brown.  If we were to use this sample to create a 95% confidence interval, we would get an interval (0.055 < p < 0.222).

The Task

Go to the website http://www.global.mms.com/cai/mms/faq.html. On the side of your screen will be information about the proportion of each color plain M&M.  You can use the data from your last web assignment or use this assignment as an excuse to buy more plain M&M's.

From the M&M web site.

 

The Process

 

  1. Record the number of each color M&M in your package.

    Brown Blue Red Orange Yellow Green Total
                                               

     

  2. Record the percentage of each color M&M in your package.

    % Brown % Blue % Red % Orange % Yellow % Green % Total
                                               


  3. What color was chosen for this project?
  4. Determine your null and alternate hypothesis.
  5. What is a Type I error?  Be specific here.
  6. What is a Type II error?
  7. Use Statdisk to test the M&M Mars company's claim about your favorite color M&M.   Submit the Statdisk prinout.

  8. Use your TI to confirm the results found above.
    Test Statistic Critical Value Significance Level P-Value
           

     

  9. Make a decision about whether or not to reject Ho;
  10. Use the flow chart on your formula card to write a well worded conclusion.

Evaluation

You are required to answer each of the above questions.  When grading your web assignment, I will be using the rubric below.  Each category (calculation, use of technology, theory and written responses) is worth 25 points.  The number of points you get per category is based on the ratings excellent, good, acceptable, poor or blank.   Use the rubric below as a self-check before turning in your assignment.

Excellent
1
(25 Points)		 Good
2
(20 Points)		 Adequate
3
(15 Points)		 Poor
4
(10 Points)		 Blank
5
(0 Points)		 Score
 

Calculations

 

No calculation or roundoff errors are present.

Roundoff errors are present.

Calculation errors present.

Calculation and roundoff errors were made.

No Calculations Shown

                    
 

Use of Technology

 

 

Shows complete and appropriate use of Statdisk & TI.

Shows appropriate use of Statdisk & TI, but a calculation error is present.

Limited or inappropriate use of Statdisk or TI.

No use of Statdisk, but TI-83 was used.

No use of Technology evident.

        
 

Theory Comprehension

 

 

Shows complete comprehension of the Statistical Theory.

Understands most of the theory, however minor errors made.

Shows some understanding of the theory, however explanations are unclear.

Shows limited understanding of the theory.

No understanding of theory evident.

         
 

Written Responses

 

Well written.  Neat, typed. No grammatical or spelling errors.

Ideas clearly presented, but spelling or grammatical errors are present.

Poorly written response.  Many spelling or grammatical errors present.

Poorly written response.  Many spelling or grammatical errors present. Assignment is hand written.

Questions left blank.

          

Conclusion

Not every package of plain M&M (or any other type) contain the same number of red, brown, blue, etc. M&M's.  We wouldn't expect them too.  Some packages will contain more, or less than others.  A certain amount of error is expected.   However, how much error is "too much"?  At what point do we say there is an error with the machinery because the company's claim does not agree with our sample?  That is the purpose of a hypothesis test.  It enables us to determine when our irregularites are sampling error and when a problem may be present.

Last updated on May 1, 2005. Based on a template from The WebQuest Page