Transcript Doing Statistics for Business

Doing Statistics for Business
Data, Inference, and Decision Making
Marilyn K. Pelosi
Theresa M. Sandifer
Chapter 17
Make Your Case
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Doing Statistics for Business
Chapter 17 Objectives
 Summary of the Techniques Covered in
your Textbook
 How to Analyze the “Great Divide” Data
Set
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Doing Statistics for Business
SUMMARY OF TECHNIQUES
Part
Chapters
Part I
Topic
Chapters 1 and 2
Getting Started
Main idea: Sample as a snapshot of the population
Part II
Chapters 3, 4 and 5
Exploratory Data Analysis
Main idea: Summarize the data in picture and numerical form
Look for the center, the spread and trends
Part III
Chapters 6 and 7
The Keys That Unlock
the Door to Inferential
Statistics
Main idea: Distributions and parameters
Link between probability and inferential statistics
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Doing Statistics for Business
SUMMARY OF TECHNIQUES (con’t)
Part
Chapters
Topic
Part IV:
Chapters 8,9,and 10
Inferential Statistics
Main idea: Use the sample to draw conclusions about the population
Part V:
Chapters 11,12 and 13
Relationships, Models and
Modeling
Main idea: Use sample data to build a model to explain the
relationship between 2 or more variables.
Part VI
Chapters 14,15,16 and 17 Additional Topics
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Doing Statistics for Business
4 MAJOR THEMES
1. Sampling Error
2. Variability
3. Relationships Between Variables
4. Decision Making in any Form should be
Based on a Proper Analysis of Data..
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Doing Statistics for Business
HOW TO ANALYZE THE “GREAT DIVIDE”
DATA SET
• Step 1: Explore the data visually using the graphical
techniques of descriptive statistics. These include
bar charts, pie charts and histograms.
• Step 2: Summarize the data numerically. This
includes finding the mean, median, quartiles, range
and standard deviation (at a minimum).
• Step 3: Look for relationships in the data visually
and numerically. Visually you would examine
scatter plots.
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Doing Statistics for Business
HOW TO ANALYZE THE “GREAT DIVIDE”
DATA SET
• Step 3 (con’t): Numerically, you should use cross
tabulation tables to examine averages and standard
deviations for subsets of the data.
• Step 4: On the basis of the results of steps 1-3,
formulate some hypotheses that might help you
answer your questions and solve the problem.
• Step 5: Test the hypotheses, being sure to check that
the assumptions of the test are not violated.
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Doing Statistics for Business
HOW TO ANALYZE THE “GREAT DIVIDE”
DATA SET
• Step 6: If there appears to be a pattern in the data
over time, use a time series technique.
• Step 7: If appropriate, estimate the parameters of a
multiple regression model for the variable you are
trying to predict.
• Step 8: Draw some conclusions from your analysis
and make some recommendations.
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Doing Statistics for Business
Chapter 17 Summary
In this chapter you have:
 Taken a global look at the techniques you learned
in this textbook, Doing Statistics for Business.
 Grouped the chapters into 5 main parts and found
4 themes that tie all of your work in this textbook
together.
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Doing Statistics for Business
Chapter 17 Summary (con’t)
 Learned the basic tools to allow you to use data
and make informed business decisions.
 Learned not only to to analyze data, but that your
analysis must always be done ethically and fairly.
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