Module 7 Activity 4

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Activity 4:  Taskstream

Now that you have completed Module 7, you are ready to do Tasks 5, 6, 7, 8, and 9 of the MQTA.  Go to www.Taskstream.com to complete these tasks.

Accessing the e-text:
You should go into MML Part III, and on the left menu bar is a button E-text—Agresti text. Click this button, and then click into any of the chapters.  From there you can click into the Chapter Opener or any section on the list.  A new window will pop-up and then you should see a page number on the top of the page.  In order to eearch for terms go into the Index, by typing IND into the box with the page number.  A search box will pop up and you will be able to type in any key words you want to look up.

Task 5--Explain randomization, replication, comparison and control in experiments.

• Statisics.com has a good glossary to help you define the terms in this task.  Here is the link:  http://www.statistics.com/resources/glossary/r/replication.php

Task 5 Checklist

• Did you correctly identify one of the controlled variables in the experiment?
• Did you identify something the scientist was unable to control?
• Did you explain the adverse effects of not controlling this variable?
• Did you explain how replication was used in the experiment?
• Did you explain why replication is an important part of an experiment?
• Did you explain the adverse effects of not using randomization?
• Did you explain the role of comparison in experiments?
• Did you explain what was compared in this particular experiment?

Task 6--Association, Causation, etc.

• Define each of the terms clearly, without using the root words.  For example if you were to define the word imagery you would not use the word image in your definition.
• For part A lurking variable is a related term, and there is information on the bullets below about how to search for terms in the Agresti e-text.
• Give examples of the terms, and be sure to cite any ideas that you borrow. Here are some helpful links that you may reference:
  

  Scatter plots, association and cause & effect: http://www.netmba.com/statistics/plot/scatter/

  Association, Correlation & Causation:
  

  www.uio.no/studier/emner/medisin/helseadm/HOKON1101/h04/Forelesningsnotater/glossary.doc 

• In the Agresti e-text to search for the terms go into the Index, by typing IND into the box with the page number.  A search box will pop up and you will be able to type in any key words you want to look up.
• For part C, ecological correlation/fallacy is a related term.  Also here are some sites to explore:
  

  Ecological Correlation

  http://www.stat.psu.edu/online/development/stat501/04linear_assoc/05linear_assoc_cautions.html
  http://www.socialresearchmethods.net/kb/fallacy.php
  http://www.encyclopedia.com/doc/1O88-ecologicalfallacy.html

Task 6 Checklist

• Did you define association?
• Did you explain how association is identified and demonstrated?
• Did you define causation?
• Did you describe more than 2 factors that influence relationships between two variables?
• Did you explain when it is appropriate to use ecological correlation?
• Did you explain what statisticians should be aware of when using ecological correlation?

Task 7--Explain the Law of Large Numbers.

• In the Agresti e-text to search for the terms go into the Index, by typing IND into the box with the page number.  A search box will pop up and you will be able to type in any key words you want to look up.
  or you may use the Berkely Statistics site: http://www.stat.berkeley.edu/~stark/Java/Html/lln.htm  
• Also, look up Gambler’s Fallacy here is a link for it: http://changingminds.org/disciplines/argument/fallacies/gamblers_fallacy.htm
• Here is a place where you can do a simulated coin toss to get your numbers http://hspm.sph.sc.edu/COURSES/J716/a01/stat.html . 
• You can stop at different points and record the numbers and percentages.  You should be able to see the Law of Large Numbers in progress.  Present the fictitious data in a table such as:

Task 7 Checklist

• Did you define the Law of Large Numbers?
• Did you explain the Law of Large Numbers using the coin toss example?
• Did you explain how the scenario is possible using a coin toss and fictitious data?
• Did you answer and explain the 1,000 Coin Tosses question?
• Did you answer and explain the Chances of Heads question?

Task 8--Sampling Task

The Australian Bureau of Statistics has a Web site with helpful information on multi-stage sampling.  Here is that link:

http://www.abs.gov.au/websitedbs/D3310116.NSF/a91a469056624a32ca256eb000026ca7/116e0f93f17283eb4a2567ac00213517!OpenDocument

Task 8 Checklist

• Did you explain why random samples are preferred to nonrandom samples?
• Did you describe the methods of 4 sampling techniques?
• Did you describe one advantage of each of the 4 sampling techniques?
• Did you describe one limitation of each of the 4 sampling techniques?
• Did you cite references (if applicable)?

Task 9--Potato Chip Task

• When stating a null and alternative hypothesis remember to include the parameter.
• The formula to calculate the test statistic as a z-score is also known as a z-test. It is implemented with a sample size greater than or equal to 30.
• Here is a site that helps to determine if it is a one or two tailed test: http://www.une.edu.au/WebStat/unit_materials/c5_inferential_statistics/one_two_tailed.html

• This site is helpful to interpret your conclusion:  http://www.uwm.edu/~oeren/Chapter%206.2Hypothesis%20TestingEXAMPLES.pdf

• This site is helpful for defining the parameter for a hypothesis statement: http://www.stats.gla.ac.uk/steps/glossary/basic_definitions.html#param

  Task 9 Checklist 

• Did you provide a correct answer including justification?

• Did you include both the null and alternative hypotheses including parameters for both statements?

• Did you define type I error?

• Did you explain how type I error relates to the example?

• Did you define level of significance?

• Did you correctly identify the level of significance for the problem?

• Did you calculate the z-score and show all relevant work?

• Did you determine if the null hypothesis can be rejected based on the test statistic?

• Did you explain how this conclusion was reached relating the results to the original question?

If you encountered difficulty with any of the concepts or practice problems, you should go to the community.  There you will be able to contact the Quantitative Literacy Math (QL Math) Course Mentors through the "Contact a Mentor" button, or e-mail.