STA 100
Looking at Data: Visual Displays
Plotting one categorical variable
Plotting one quantitative variable
Using the homerun.mtw data set
60
Ruth
50
40
30
20
Index
1921
1923
1925
1927
1929
1931
1933
More Time Plots (hour-earn.mpj)
Average Hours and Ear
STA 100: Statistical Foundations
Fall 2007
1)
[25]
TEST #1
[points are in bold]
Name_
There are 3 steps we do BEFORE statistics (Note: NOT the 3 steps OF statistics). Describe these three steps
we do before statistics and mention how the population, indiv
STA 100: Statistical Foundations
Fall 2007
1)
[15]
Name_
TEST #1
[points are in bold]
There are three steps in DOING statistics (Note: NOT the 3 steps BEFORE doing statistics). Describe
these three steps in DOING statistics and mention how the population,
STA 100: Statistical Foundations
Spring 2009
1)
[12]
TEST #1
[points are in bold]
Name_
There are three steps in DOING statistics (Note: NOT the 3 steps BEFORE doing statistics). Describe
these three steps in DOING statistics and mention how the populatio
STA 100: Statistical Foundations
Fall 2008
TEST #2
[points are in bold]
Name_
1)
You are given the following 13 ages (in years): 16, 22, 5, 41, 1, 21, 34, 25, 19, 20, 6, 30, 32
[7]
a) Give the 5 number summary for this data set.
1, 5, 6, 16, 19, 20, | 21|
OLD TEST #2 QUESTIONS
3)
[10]
What does correlation measure (Include the types & number of variables) ? Does it measure all types
of association? Explain.
4)
[15]
Two types of bias that can turn up in random samples are Undercoverage & Nonresponse bias.
D
STA 100: Statistical Foundations
Fall 2008
1)
[10]
TEST #2
[points are in bold]
Name_
Two types of bias that can turn up in random samples are Undercoverage & Nonresponse bias.
Describe each & give examples of each (Show how they might bias results).
Unde
STA 100: STATISTICAL FOUNDATIONS
Coe College
Fall Term 2009
The Main Goals of this Course
To teach you what is (and is not) the study of statistics
&
To teach you how to look for information in data
Instructor
Office
Hours
Gavin Cross
Phone
314 Stuart Hal
STA 100
Collecting Data: Sampling Methods
Here are the 5 main types of sampling methods
Real World Sampling Situations
What type of sampling method are you using?
For the information needed, how likely is it that the sample is representative of the popula
Population vs. Sample
Looking at Distributions (from the web)
-From Here on we assume we have a simple random sample (SRS) unless otherwise stated.-Each population variable has a fixed distribution.
We saw in "Looking at Data" that we can find a sample
va
STA 100
Other Plots & Bad Plots
CNN.com posted misleading graph showing poll results on Schiavo case
In presenting the results of a CNN/USA Today/Gallup poll, CNN.com used a visually distorted
graph that falsely conveyed the impression that Democrats far
STA 100
1)
[4]
TEST #2 (Population vs Sample, CLT & the Normal)
Solve the following two problems
a) If Z is N( 0, 1), find the chance that Z > 2.14
= 1 0.9838 = 0.0162
[4]
b) If Z is N( 0, 1), find the chance that -1.24 < Z < - 0.61
= 0.8925 - 0.7291 = 0.
STA 100:
TWENTY OLD TEST #1 QUESTIONS
The points each question was worth is shown in bold brakets
The answers are in red (these answers may not be complete)
1) What are a histogram and stem plot both used to show (Include the # of variables & type)? What
STA 100
Looking at Data: Number Summaries
Number Summaries for one quantitative variable
Measures of Location
Number Summaries for one quantitative variable
Measures of Spread
Example: Below is a boxplot of Calories by Type for the
hotdogs.mtw data set.
I
STA 100
Histogram Exercise: Matching Variables to Histogram Shapes
Match the following variables to the most likely histogram. (There is a one-to-one pairing)
A.
Scores on a fairly easy exam in statistics (Higher score is better)
B.
Number of cycles (mont
CI: x bar +/- Z * [x bar / (s / sqrt(n)]
Z = [x bar-x] / [std. dev / sqrt(n)]
If n is less than 30
T= [x bar-x] / [s / sqrt(n)]
.1 = Political Polling
.05 = Consumer Research
.01 = Quality Control
Type 1 error = when we reject a true H(0) - alpha
Type 2 e
STA 100: Statistical Foundations
Spring 2009
1)
[15]
TEST #2
[points are in bold]
Name_
There are two types of question bias that can occur in a survey. Name then and describe how they
can bias the results of a survey. Is there anything you can do to get
STA 100: Statistical Foundations
Spring 2009
1)
[15]
TEST #2
[points are in bold]
Name_
There are three types of interviewer bias that can occur in a survey. Name them and describe how they
can bias the results of a survey. Is there anything you can do to