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Scatterplot of income vs College math courses
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College math courses
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Statistical studies are done routinely in our society to find important information about medical issues, to discover interesting facts about political situations, and to test opinions about educational ideas. As part of the course requirements for MATH 131, you will carry out your own statistical study on a population you choose. The data that you collect for LAB 1 will be your database for the entire project, which will consist of a total of nine labs over the course of the semester.
You MUST have a folder for submission of your labs throughout the semester. The folder should have two pockets: one pocket to hold graded labs and one to hold the lab being submitted for grading. ALL labs should be handed in every time a lab is graded; keep all of the labs in the folder.

MATH 131
Lab 1
8/11
How to begin:
Step 1: Decide upon a population that is interesting and available to you. Your population size
must be more than 40 for your project. As soon as possible, check your idea with your
instructor. This step is crucial. You do not want to proceed unless your instructor has
verified that your idea will work.
Step 2: Identify 3 variables that you will study for this population: one qualitative and two
quantitative.
What to tell your instructor:
1) Your general idea: (e.g. I am a Political Science major and I am interested in learning about
2) members of the U.S. Senate.)
Identify your population (IT MUST BE LARGER THAN 40!)
(e.g. The 100 members of the U.S. Senate is my population.)
(e.g. qualitative variable, V
1
- political party quantitative variable #1, V
2
- number of terms served quantitative variable #2, V
3
- current age)
Step 3: After you discuss sampling techniques in class, you can plan a sampling strategy for collecting your data. Make sure that you have your idea approved by your instructor.
Step 4: Using one of the sampling techniques, you will choose a sample of 40 elements from your population. For each of these 40 elements, you will collect 3 pieces of data.
Step 5 Write up Lab 1 following the guidelines below. Hand in by the deadline given in class.
The instructions below specify the format for writing up Lab 1; points towards the grade are in the left margin:
(2 points) 1. What is the interesting question that you are trying to answer with your study? What do you anticipate finding as you study your variables and their relationships? (This should be a sentence or two.)
(2 points) 2. Clearly identify your population. Remember that your population size must be greater than 40. (This can be done in one sentence.)
(1 point) 3. Identify THREE variables (See p. 11) that apply to each element in your population. One should be a qualitative variable and the other two should be quantitative variables.
Compute the range for each of the quantitative variables. The range is the largest value
2

MATH 131
Lab 1
8/11 minus the smallest value. Call V
2 the quantitative variable with the smaller spread
(range) and V
3 the quantitative variable with the larger spread (range).
V
V
1
2
,
,
Qualitative Variable _________________________
Quantitative Variable with smaller spread _________________________
V
3
, Quantitative Variable with larger spread_________________________
(3 points) 4. Clearly and in detail, explain the sampling procedure you used to collect your sample of size 40 from the larger population. (This should be a paragraph.) (See p. 22-24)
(2 points) 5. List the raw data (the actual values) that you have collected. This will be a list that is 3 columns of data for 40 lines of data. An example of a raw data list might be:
NAME (OPTIONAL)
Jones
Smith
Ford
V
1
: Political Party
Democrat
Republican
Democrat
. . continue for 37 more rows
V
2
: Number of Terms
3
2
4
V
3
: Age
39
52
52
Minitab Directions
To get random numbers to select a simple random sample, number everything in your population and generate 40 random numbers.
Create a column of integers that go from 1 to your population size:
Click Calc
Make Patterned Data
Simple Set of Numbers
Store patterned data in c1
From the first value 1
To last value enter your population size
Click OK
Now select 40 of those integers.
Click Calc
Random Data
Sample from columns
Sample 40
from c1
Store samples in c2
OK
3