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Transcript of 1 WELCOME TO MARKETING/BUSINESS RESEARCH. 2 MARKETING RESEARCH Definition: Used to implement the...
1
WELCOME TO MARKETING/BUSINESS
RESEARCH
2
MARKETING RESEARCH
Definition:
Used to implement the ____________
What is that?? (think intro)
3
Research is used to:
Identify problems/opportunities
4
Research is used to:
generate, and refine marketing actions
5
Research is used to:
Plan and Implement the Marketing Mix
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Research used to:
Monitor marketing performance
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When is Market Research Warranted:
Time Constraints
Availability of Data
Nature of Decisions
Costs vs. Benefits
8
Sources of Marketing Data
Internal sales records customer
complaints inventory ...
External Syndicated Standardized Customized Advertising
Agencies Field Services Tabulation Houses Commercial
Databases
9
Research is NOT a Cure-All!
Classic Blunders
10
Why do I have to be here?
You will use research for decisions
Can easily bias research
Numbers lie
11
RESEARCH ETHICS
12
In The Beginning 1950 Fear and Authority Studies
Animal Protection
Internal Review Boards http://www.wvu.edu/~rc/irb/
irb_guid/exempt.rtf
13
Business Ethics
Definition:
14
Teleological Ethics Definition:Teleological moral
systems are characterized primarily by a focus on the consequences which any action might have (for that reason, they are often referred to as consequentalist moral systems, and both terms are used here). Thus, in order to make correct moral choices, we have to have some understanding of what will result from our choices. When we make choices which result in the correct consequences, then we are acting morally; when we make choices which result in the incorrect consequences, then we are acting immorally.
15
Deontological Ethics Definition:Deontological moral systems
are characterized primarily by a focus upon adherence to independent moral rules or duties. Thus, in order to make the correct moral choices, we simply have to understand what our moral duties are and what correct rules exist which regulate those duties. When we follow our duty, we are behaving morally. When we fail to follow our duty, we are behaving immorally.
16
Kohlberg – Value Maturity Model Three levels of maturity with six
stages of development Self-centered level – (1) obedience and
punishment, (2) naively egoistic orientations
Conformity level – (3) good person, (4) “doing duty” orientations
Principled level – (5) contractual legalistic, (6) conscience of principle orientations
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Which is the “right” perspective
18
Respondent’s Right to Choose Can’t force compliance
Captive subject pools Status of the researcher
Insure that incentivesdo not create pressure
19
Respondent’s Right To Safety
Preserve anonymity Preserve privacy No mental stress
respect subjects debrief subjects
Protect when questions are detrimental to subject
Inform when special equipment used
20
Respondent’s Right to be Informed
Informed consent/assent Parental consent Observation??
consider risks consider alternative methods
Deception
21
Solutions Actively think about ethics when
designing the study http://cme.cancer.gov/c01/
Government Institutional Review Board
Ethics Codes AMA
Ethics Checklist
22
THE RESEARCH PROCESS
Stages in the Research Process
23
Define the Problem (Stage 1)
Research objectives
Research questions
Properly formulate the problem
24
Conduct a Situation Analysis -- Part of Problem Definition
General environment
Competitive products or services
Consumers
Marketing Programs
25
Determine Research Design (Stage 2)
How much should you spend?
What type of design should you use? exploratory descriptive causal
26
Exploratory Designs
Used when you do not have a good understanding of the problem and need to gain insight Used to:
Methods:
27
Descriptive Designs
Used to describe the characteristics of consumers, competitors, etc.…
Methods
28
Causal Designs
Used to determine cause and effect relationships. MUST use experiments which
include:
29
Preparation of the Design
Determine source of the data primary secondary
Determine data collection method qualitative quantitative
30
Sampling(stage 3)
Sampling defined:
Who is to be sampled (the target population)?
How big should the sample be? Which sampling technique should be
used?
31
Data Gathering(stage 4)
Method Used
Stages
32
Data Processing and Analysis (Stage 5)
Editing
Coding
Analysis
33
Conclusion and Report Preparation (Stage 6) Written--the only tangible from the
study interesting easy to read managerial implications
Oral interesting convincing
34
Secondary Research
The Place to Begin
35
Secondary Data
36
Secondary Data Advantages
Time Money Improve over other studies Point of comparison for trends Increase understanding of problem
37
Secondary Data Disadvantages:Problems of Fit
Measurement units differ
Class definitions differ
Out of date
38
Secondary Data Disadvantages:Problems of Accuracy
Primary vs. secondary source
Purpose of publication
General evidence of quality
39
Internal Secondary Data Sales invoices Warranty cards Departmental
records Sales records
40
Locating External Secondary Data
Identify what you need to know Develop a list of key terms and
people Examine directories and guides Write letters to key contacts Talk to reference librarian Do a computer search Pull the information together
41
THE LAWAlways conduct secondary
data search before you do primary data collection.
42
Qualitative Interviewing Techniques
1. Focus Groups2. Projective Techniques
3. Depth Interviews4. Observation
43
Definitions (Yuck!):
Inquiry -- Person responds to a set of Questions
Disguised:
Undisguised:
44
Final Definitions (I promise):
Structured: Questions: Answers:
Unstructured: Questions: Answers:
45
Qualitative Methods
“Touchy-feely” – no numbers Examine thoughts, feelings,
motivations… Can be results be projected to the
population? Yes No Can spot trends 3 to 4 years before
they show up in surveys
46
Focus Groups
______ homogeneous people carefully recruited
Lasts _____
Types: Round-table (Comfortable room with one-way
mirror) Telephone Internet
Moderator Guide
47
Focus Group Moderator Keeps discussion focused Truly believe that participants have
wisdom Encourages shy to talk and dominant
participants to be quiet Should say little, but keep eye contact Accepts all answers Must be a quick study
48
Uses of Focus Groups
49
Advantages/Disadvantages of Focus Groups
Advantages:1.2.3.4.5.6.7.
Disadvantages:1.2.3.4.
50
Conducting a Focus Group Register
participants (demographic information)
Small talk Introductions
welcome why they are here guidelines or ground
rules opening question
Ask questions Anticipate flow Control your
reactions Probe as needed Summarize the
discussion
51
Conducting a Focus Group:Guidelines
Always Include:taping discussiondo not talk over othersno names attachedsponsor of studyrole of moderator to guide onlyfeel free to talk to each otherdone byfirst name basisno wrong answers only differing opinions
May Include:don’t need to agree but listen to their viewsno cell phones or pagerswho will listen to tapeswho will see the reporthow the report will be usedstrictly research and no saleslocation of the bathroomshelp yourself to refreshments
52
Developing Questions for Focus Groups
Where to Begin:
General Rules:
53
Question Categories
Opening questions Introductory questions Transition questions Key questions Ending Questions
54
Projective Questions: Used when subjects
cannot or will not directly communicate feelings
“A man is least himself when he talks in his own person; when he is given a mask he will tell the truth.”
E.g., TATs, inkblot
55
Word Association
Examine brand/service image Measure frequency of responses
and no responses Response Latency
Example
56
Sentence Completion Gives more
direction than word association
Examples: When visiting the
President be sure to_____________.
57
Unfinished Story Finish the story or
tell why the person acted the way he or she did.
58
Third Person Role Play
What would the typical person do in this situation?
We tend to think others are like ourselves, yet we are more willing to tell the truth about “others”
Example: Why would your neighbor buy a
Mercedes
59
Cartoon Completion Subjects fill in the
bubble – suggests a dialogue between the characters
60
Draw a Picture
Subject given a topic to draw Examples:
61
DEPTH INTERVIEWS
One-on-one interviews
Try to uncover underlying motivations, prejudices and attitudes toward sensitive information
62
Depth Interviewing Analysis
Laddering
Attributes
Consequences
Values
Coca
Cola
63
When to use depth interviews:
Sensitive subject matter Need intensive probing Respondent interaction unlikely to
be helpful Have lots of $$$$ and time Need detailed responses (> 15
minutes)
64
Some Boring Definitions:
Ethnographic/Observational Research
Direct Observation:
Indirect Observation
65
Observation can be disguised or undisguised
66
Observation of Physical Objects
Naturalist Inquiry
Physical Trace evidence wear on floor tiles
Garbology
Pantry Audit
67
Mechanical Observation Television/Internet
Scanners
Eye Tracking
Psychogalvanometer
Response Latency
68
Experimental Research Methods
Looking at Cause and Effect Relationships
69
Experiment
Definition:
variable manipulate independent variable dependent variable
70
Requirements for an Experiment
Must have two or more groups of subjects experimental group(s) control group(s)
Must use random assignments to groups controls for extraneous factors
71
Research Environments
Laboratory experiment
Field experiment
72
Can NEVER prove causation ( X Y)
Can only INFER such a relationship
73
Reasons for Association between X & Y :
Common causes drowning and ice cream consumption
Confounded factors AIDS test of Rivavion
Coincidence Causation
74
Evidence to Support Causation
Concomitant Variation Temporal Ordering (time order of
occurrence)
Elimination of Other Causes
75
Concomitant Variation Required for Causation
1. Concomitant variation
positively negatively
76
Temporal Ordering Required for Causation
77
Elimination of Other Possible Causes Required for Causation
You must think this through, no one will give you a list to check
Most difficult of the criteria to determine
78
Internal Validity Definition:
Threatened by: history maturation instrumentation selection bias (non-random assignment
) testing
79
External Validity
Definition:
Threats to external validity reactive/interactive testing effects
surrogate situations
demand artifacts
80
Experimental Designs --Notation:
RR = random assignment of respondents
X = exposure to one of the possibly many treatments
0 = observation of measurement of the respondent
T = treatment effects
81
One-Shot (After Only)
X O
Problems?
82
One-group Pretest-Posttest
O1 X O2
Problems?
83
Static Group
X O1
O2
PROBLEMS?
84
Before/After With Control
RR O1 X O2
RR O3 O4
Problems?
85
After Only With Control
RR X 01
RR 02
Problems?
86
SURVEY INTERVIEWINGTECHNIQUES
Methods that Use Large Sample Sizes and Create
Results that Can Be Projected to the Populations
87
Mail Surveys/Self-Administered Questionnaires
Def:
-cold-panels-fax- e-mail
88
Internet/Computer Assisted Surveys
Allow for lots of branching/interactive
Allows for personalization
Great anonymity
Representative Samples
89
Other Survey Methods Telephone
Personal in-home (Door-to-Door) -
Mall intercepts
-can interact with product replacing ___________
90
Each Method Has Advantages and Disadvantages
See page 172 for a summary
TREND – USE A COMBINATION OF METHODS
91
Things to consider when choosing method
Versatility - Visual cues
- Degree of structure
- Complexity of questions
92
Consider Quantity of Data Function of
questionnaire length - shortest
________
- moderate length ________
-longest _________
93
Consider Sample Control Contact the right people
mailing list quality
interviewer qualifying
phone unlisted
Random Sampling error
94
Consider the Quality of Data
Response bias (see next slide) Interviewer bias Interviewer cheating Poor questionnaire design Sample bias
Systematic Errors
95
Response Biases
Acquiescence Extremity Interviewer Auspices Social Desirability
96
Consider Non-Response Error
Problems occur because the people responding to the questionnaire differ significantly from those not responding
Possible Self-selection bias Example
-survey 500 students to see if they need transportation to and from school - 50 answer and say yes
-conclude that all 450 that did not answer do not need it Did you make the correct conclusion?
97
Your Turn
Make up your own example of nonresponse bias:
98
How to Increase Response Rate
Prior notification Motivate with
rewards
Good looking questionnaires
Good cover letter Follow-up
Make it fun!!
99
Consider Speed Phone is ____
Computer-assisted phone/internet is _____
Mail is ____
100
Consider Cost Internet:
relatively inexpensive
Mail: depends on pre-contacts and follow-ups
Telephone: next most expensive
Mall/In-home $30 up to $100
101
Specific Uses for Methods Cold mail
respondents very interested in topic Mail panels
general information, in-home use Phone
nationwide samples Mall intercept
copy tests, product tests, branding/package testing
102
Measurement
Assigning Numbers To Reflect the Degree or Amount of a
Characteristic
103
MEASURES OF CENTRAL TENDENCY
MODE
MEDIAN
MEAN
104
Measurement Scales Series of items that
are arranged progressively according to value or magnitude
A series into which an item can be place according to its quantification
105
Nominal Scale
Identification only
No order to the numbers
Examples:
Measure of Central Tendency:
106
Ordinal Scale
Ranked data
Distance between two numbers is unknown and uneven
Examples:
Measure of Central Tendency:
107
Interval Scale
Rank to the data
Equal distance between numbers
No “natural zero”
We assume a lot of scales are interval
Measure of Central Tendency:
108
Ratio Scales
Rank to the data
Equal distance between numbers
“natural zero” where zero means “none”
Measure of Central Tendency:
109
YOUR TURN --Write a question for each type of scale
Nominal
Ordinal
Interval
Ratio
110
Criteria For Good Measurement
Reliability
Validity
Sensitivity
111
1) Reliability of Scales
Coefficient Alpha Are the results on
questions measuring the same thing consistent?
Single item scales more suspect to random error
Test/retest Are consistent results
found on repeated measures
112
2) Validity
Are we measuring what we think we are measuring?
Content validity (Face validity)
Pragmatic validity
113
3) Sensitivity Refers to an instruments ability to
accurately measure variability in stimuli or responses
Example: I love to eat chocolate Agree vs Disagree
Strongly mildly neither mildly strongly agree agree agree or disagree disagree
disagree
114
Noncomparative Continuous Graphic Rating Scales Place a mark on the line indicating
how important it is to have each of the following at your vacation resort:
Alpine slides _____________________unimportant important
5 inch line 127 mm 1/20 inch
115
Graphic Rating Scales
Happy faces
Thermometer
116
Noncomparative Itemized Rating Scale Several categories from which the
respondent can choose
Top-box method: How likely are you to buy a Sony DVD player in the
next 3 mos. definitely will buy Probably will buy Might buy Probably will not buy Definitely will not buy
117
Examples of Itemized Rating Scales
Likert
Semantic Differential
Staple
118
Likert-type Scales
Sentences with which the respondent agrees or disagrees
It would be cool to have a candy-red 1965 convertible Mustang
SD D Neither A SA
119
Likert-type Scales
Code such that higher numbers mean better things
Can create summated scales to form an index
Assume __________ scale
120
Semantic Differential
Series of attitude scales where repeated judgments about a concept are made
Opposite adjective words or phrases Use several of these and sum them
Fast __:__:__:__:__:__:__ SlowBad __:__:__:__:__:__:__ GoodService ServiceTasty __:__:__:__:__:__:__ Not TastyFood Food
121
Semantic Differential
Code such that higher numbers mean better things or more of something
Make an overall score--sum the items Develop a snake diagram (image
profile) to compare competitors
Assume _____ scaling
122
Staple Scale
Use +5 (describes completely) to -5 (does not describe at all)
Assume _______ scaling Good for phone Easy to construct May look difficult for respondent-5 -4 -3 -2 -1 FUN +1 +2 +3 +4 +5
123
Questions for Itemized Response Scales
How many categories?
Balanced or Unbalanced?
Should you have a neutral point?
Forced or unforced?
124
Comparative Scales
Compare one set of objects directly with another sensitive easy can create artificial differences
125
Paired Comparison
Which do you prefer?____ Barry Manilow____ Counting Crows
____ Barry Manilow____ Rolling Stones
____ Rolling Stones____ Counting Crows
126
Paired Comparison Table
Manilow Crows Stones
Manilow ----- 0.90 0.85
Crows0.10 ---- 0.60
Stones 0.15 0.40 ----
127
Calculation of Rank-Order Values
Manilow Crows StonesManilow
Crows
Stones
128
Rank-order Scales
Respondents are simultaneously presented with several objects that they rank order
Please rate the following from 1=most preferred to 4= least preferred
Pizza Hut -Domino’s Mario’s -Little Ceaser’s
129
Comparative Continuous Graphic Rating Scale
Similarity ratings used for perceptual maps
Pitt and WVU _________________________Exactly Completelythe same different
130
Constant Sum Scales
Assign chips or points to attributes
Very careful with instructions
Difficult for the respondent
131
Developing Questionnaires
The Art and Science of Questionnaire Design
132
Preliminary Considerations
What information is required?
Who are the target respondents?
What data collection method will be used?
133
Managerial Orientation
Make sure that all information in the questionnaire is useful to the manager (demographics
and first question are possible exceptions)
134
Make Sure Questions Are Understandable
Do you need more than one question?
Do respondents have the information needed to answer the question?
135
Understandable Questions, cont.
Can respondents remember the information?
Is it too much work to get the information?
136
Ways of Dealing with Sensitive or Embarrassing Questions State behavior is not unusual. Early or late in the questionnaire?
early late Give categories for responses. Phrase how others might act.
137
Need Mutually Exclusive and Exhaustive Responses
Responses should not overlap
Must cover the entire range
Example:
138
Use Natural and Familiar Language
Simple language
Language that the target market uses
Avoid ambiguous words: DO NOT USE:
139
Avoid Bias
No loaded questions
Watch for sequence bias
140
No Double-Barreled Questions
A question that calls for two responses
141
Response Formats
Open ended--respondent answers in his or her own words
Uses:
Bad points:
142
Itemized Questions (close-ended)
Fixed alternatives Advantages:
MUST PRETEST
143
Types of Close-ended Questions
Multichotomous (More than 2 responses)
Dichotomous (Only two responses)
144
Questionnaire Flow
Cover letter
First question very important, must be _____________ _____________
Demographics late in the questionnaire
145
Sequencing
Funnel
Inverted funnel
Keep questions on related topic together
Be very careful with branching
146
Layout
Booklets for multi-page questionnaires
Attractive Title, date, return
address on first page
Color code branching
147
Layout
Number the questions Put the answers in all UPPER CASE
letters What is better?
white space save a page
148
Pretest the Questionnaire
First with a personal interview
Make corrections Next using the
real method If you do not
pretest, you are being __________________
149
Sampling
The Statistical Adventure Begins
150
Populations
Def:
Census
Sample
Which is better? census? sample?
151
Step 1: Define the Target Population
Must be very specific: What is a user? What demographics matter? Are there geographic boundaries? What is the relevant time period?
What is an element?
152
Step 2: Specify a Sampling Frame
Def:
153
Sample Frame Problems
List may not match the target population
over-registration
under-registration
154
Step 3: Selecting a Sampling Method
Probability samples
example: Non-probability samples
example:
155
What’s the Big Deal?
Probability samples let us estimate _________
We can calculate a confidence interval
So, probability samples are more representative than non-probability samples. true false
156
Simple Random Sampling
Probability sample Number each unit in the sampling
frame Pick ___ units using a random
numbers table NOT haphazard
157
Take a Simple Random Sample (SRS) of n=3
Element Attitude toward Motel 6Natasha 6Scotty 7Kalie 4Lynn 2Gregory 8Paul 4John 7
158
Stratified Sample
Decide on stratification variable
homogeneous groups related to dept. variable
Divide population into a few mutually exclusive and exhaustive strata
Take a SRS from each strata
159
Proportionate Stratified Sample
Choose sample from strata in same proportion as they are in the population
Population SampleStrataproportion proportion
160
Disproportionate Stratified Sample
Take a larger sample from the strata with ________ variance
What is variance?
Exercise: Develop two populations with 8 elements each. Population 1: high variance, low mean Population 2: low variance, high mean
161
Disproportionate Stratified Sample
Population Sample
StrataVarianceproportion proportion
162
Why use Stratified Samples?
Make sure that you include certain subgroups
More precise, IF we use the right stratification variable margin of error is ___________ sampling distribution is __________ confidence intervals are __________
What is the right variable?
163
Cluster Sampling
Divide population into lots of heterogeneous clusters
Take a SRS of clusters Either:
sample all elements in the selected clusters
OR take a SRS of elements in the selected clusters
164
Why use Cluster Samples
Cheap Easy Likely to be the
way the sampling frame is set up
Problem not precise, lacks
statistical efficiency
165
Non-probability Sample: Cannot estimate margin of error
Convenience or accidental sample
If the sample size is really large, we know we have a representative sample true false
166
Judgment or Purposive Sample
Elements selected because they can serve the research purpose--they are believed to be representative
Snowball sample
167
Quota Sample
Attempts to be representative by sampling characteristics in the same proportion as the population
Interviewer chooses sample
Are these representative? _____
168
Step 4: Determine the Sample Size
Must take into consideration: cost time industry standards statistical precision
Discuss this in detail in the next chapter
169
Step 5: Select Elements
Actually collect the data Clean-up the data Put the data into the computer
170
Characteristics of Interest
Population
N
U (mu)
o2 (sigma squared)
O (sigma)
Samplen
X (x bar)
Sx2
Sx
# of elements
Mean
Variance
Standard Deviation
171
Step 6: Estimate the Characteristics of Interest
Sample mean:sum of the sample elements
X= number of elements in sample
Sample variance = Sx 2
sum of deviations around the mean squared
sample size minus 1
172
Sample Standard Deviation
The square root of the sample variance = sx
Has a specific meaning
173
Sampling Error
The difference between the : population parameter
and the sample statistic
We look at confidence intervals to estimate this but not until the next chapter
174
Non-sampling Error
(i.e., all other kinds of errors except for sampling error!)
175
Types of Non-Sampling Error
Sampling frame
Poor questions
Poor branching
Item non-response
176
More Non-Sampling Errors
Non-response
Interviewer bias
Interviewer cheating
Coding and editing problems
177
Which is the Larger Problem?
Sampling error
Non-sampling error
178
Sample Size Determination
Everything You Ever Wanted to Know About Sampling Distributions--And More!
179
Sampling Distribution
A frequency distribution of all the means obtained from all the samples of a given size
Example: $$ spent on CD’s at Tracks Daffy 34.00 Donald 72.00 Sylvester 36.00
All samples of n=2
180
Your Turn
Develop a sampling distribution using n=2
Calculate the population mean CAR
A B C D E
Expected 3 4 5 0 1Life
181
Sampling Distributions
The distribution of sample means is skinnier than the distribution of elements Why?
The distribution is normal The sampling distribution mean
equals the population mean
182
Standard Error
The variability in the sampling distribution
Tells you how reliable your estimate of the population mean is
If this is big (good or bad) If this is small (good or bad) WHY?
183
Standard Error
Sx standard deviation
square root of the sample size
As the samples size gets bigger, the standard error gets __________
184
Confidence Intervals
CI= Xbar +/- z (standard error) Where:
z= _____ for 68% confidence z= _____ for 95% confidence z= _____ for 99.7% confidence
What confidence level should you use?
185
Develop a Confidence Interval
Estimate the average number of trips to the beach taken by WVU students during their 4-6 year career xbar = 5 SD = 1.5 95% Confidence
Level n=100
186
So,
There is a 95% chance that if all WVU students were sampled regarding the number of beach trips that the findings would differ from our results by no more than ____ in either direction.
187
or, maybe better, If I were to conduct this study 100
times, then I would get _____ different confidence intervals. If I have a 95% confidence interval the ____ of the 100 CI’s will contain the true population mean (mu) and ____ will not.
I sure hope that the confidence interval I got is one of the 95 that contains mu!
188
Confidence Interval Issues
Reliability how often we are correct
Precision how wide the confidence interval is
The smaller the n, the _____ the CI Given a particular n, the CI will be
_______ when we increase the reliability
189
Factors that Influence n Precision (H)
how skinny must can your CI be in order to be able to take action on the results?
I will go to a water park. DW PW Maybe PWN DWN
I will pay _____ for a musical card.
I will pay _____ for a motorcycle.
190
More Factors That Influence n
Confidence level (z)
Population SD
Time, money and personnel
191
Sample Size for Interval or Ratio Data
Z2
n= H2 * s2
Where:z= 1, 1.96, or 3
H= precision (+/-) Hs2= variance (or standard deviation
squared)
192
Example: Average Number of Books Bought Per Semester
H=0.25 s=1.5 Confidence =
95%
193
Sample Size for Nominal Data
Z2
n = H2 * (P) (Q)Where:
Z= 1, 1.96, or 3H= a percentage (e.g., 0.03--NOT 3)P = initial estimate of the population proportionQ= (1-P)
194
n for Proportion of WVU Students Who Read the DA
Do you read the DA?
1. YES 2. NO
Estimate that 60% read the DA
Want a 99 % CI Want a +/- 3%
precision
195
The Final Sample Size
Compute n for all nominal, interval and ratio questions most conservative
limited resources
196
Non-statistical Approaches to n
All you can afford method: subtract costs from budget
figure out cost per interview
divide leftover budget by cost per interview
Rules of thumb
197
Coding and Editing
Getting the data ready for analysis
198
Coding Each response must have its own
variable name
Variable names can have up to 8 characters
Assigning numbers to responses to enter data into computer
199
Creating a Coding Sheet Must have a filename at top of
questionnaire Name_data.txt
First variable is ALWAYS the ________Why?
Write the variable names on the questionnaire next to the matching response
200
Coding Coding Open-Ended Questions:
Code open-ended nominal __________ EX: What State is your current state of residence?
Code open-ended numerical – enter _______ Ex: How much would you pay for this product?
201
Coding Coding fixed-alternative responses:
Assigned numbers should be logical
One variable needed for each answer the respondent will give rank order
semantic differential
“Check all that apply”
202
Editing
Cleaning up the data
Field edit check for legibility check for completeness
203
Office Editing
Outliers
Missing data
Blunders
Inconsistencies
204
Hypothesis Testing
Using the SAS System to Analyze Questionnaires
205
Statistically Significant
Are these results for real, or did they just occur by chance?
Remember, in sampling, all numbers have ranges
206
Alpha and p-values
Alpha value: the error rate you
are willing to accept
P-value the error
associated with rejecting the null hypothesis
207
Chi-square & T tables
For BOTH distributions Area under the curve
= Alpha & p-value are
areas under the curve critical value--
associated with an alpha level
calculated value--associated with a p-value
t-distribution
chi-square distribution
208
Chi-Square Goodness of Fit
When to use: number of variables ________ scaling of variable _________
Basic idea: could the numbers you get (the
observed value) come from a population which has the pattern I expect? (the expected value)
209
Chi-square Goodness of Fit
Ho: This sample could have come from a population which has this pattern: __________________________________ __________________________________
Ha: There is a different pattern in the population than I expect (or hope).
210
Chi-Square Goodness of Fit
Chi-square calculated= sum of (Observedi -Expected i ) 2
Expected i
degrees of freedom = number of cells - 1
Alpha Value Table Value
211
Now Graph
chi-square calculated
chi-square table value
212
Chi-Square Goodness of Fit
What type of dairy treat do you like best?1. hard scoop ice cream2. soft serve ice cream3. chocolate covered
ice cream bars
Ho:
Ha:
Chi-square Calculated:
Degrees of Freedom:Chi-square Table:Graph
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Chi-square Goodness of Fit Rules
If the chi-square calculated is in the tail, then _______ Ho; conclude the pattern in the data. is NOT what you expected or wanted.
If chi-square calculated is in the hump, then _______ Ho; conclude, the pattern IS what you expected or wanted.
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Do It Yourself Using SAS --
What is the pattern for the favorite brand of soda?
Ho:
Ha:
Chi-square Calculated:
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Do It Yourself Using SAS --(cont.)
Degrees of Freedom: Chi-square Calculated: Chi-square Table: Graph
Conclusion:
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Chi-square for Two Variables
When to use: number of variables ________ scaling of variables ________
Basic Idea: Compare the values you actually get
from you study to the values you would expect if there was ____________between the two variables
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Chi-square for Two Variables
Ho: There is no relationship between ____ and _____
Ha: There is a relationship between ____ and _____; SPECIFICALLY _________________
NO CALCULATIONS!! SAS DOES THIS ONE
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Chi-Square for Two Variables
Alpha level
Probability level
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Chi-Square for Two Variables
If the probability level is > _____, do not reject Ho, conclude________________
If the probability level is < _____ then reject Ho, conclude ______________ AND specify the nature of the relationship.
CAREFUL--Do not just assume that the relationship you predicted is correct
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If you Reject HO -- How Strong is The Relationship?
Look at Phi Phi < 0.10 is
______ Between 0.11 and
0.40 is __________ Phi > 0.40 is
_______
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Do it yourself using SAS
Ho:
Ha:
Chi-square calculated: Probability level: Alpha level Phi: Conclusion:
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Rank-Order Tests
It’s 12:00. Do you know what
your Ha is?
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Rank-order Data & Chi-square
When to use: number of variables ________ scaling of variable ________
Basic idea: compare the observed value (________________) with the values you would expect if NO PREFERENCE was shown in the data
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Hypotheses & Calculations
Ho: There is no ranking in the data--there is no preference.
Ha: _____________________________, specifically, ______________________.
Chi-square calculated:Sum of (Observedi -
Expectedi)2 Expectedi
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Rank-order Chi-square First, multiply the rank-order data for each
variable Variable 1 score = 1 (___) + 2 (___) +3 (___) ... Variable 2 score = 1 (___) + 2 (___) +3 (___) ... Variable 3 score = 1 (___) + 2 (___) +3 (___) ...
Compute expected value Add up the total scores and divide by the
number of variables
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Example
Ranking of movies: Mulan, Private Ryan, Titanic (n=20)
Mulan PR Titanic1 10 7 32 4 8 8
3 6 5 9
Mulan ranking = 1 (___) + 2 (___) +3 (___) PR ranking = 1 (___) + 2 (___) +3 (___) Titanic ranking = 1 (___) + 2 (___) +3 (___)
Expected value:
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Rank-order Chi-square
Degrees of freedom Alpha level Chi-square table Graph chi-square and
chi-square calculated Conclude Managerial
implications
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Rules If the chi-square calculated is in the
tail, then _______ Ho, conclude that there is a preference shown in the data. EXAMINE THE DATA TO DETERMINE PREFERENCE. (It may not be what you hypothesized!)
If the chi-square calculated is in the hump, then ___________ Ho. Conclude there is no preference shown.
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Do This With the Soda Rankings
Rank calculations
Expected value Ho:
Ha:
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Do This With the Soda Rankings (continued)
Chi-square calculated:
Chi-square table: Graph:
Conclusion: reject or do not reject Ho Managerial implication
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T-test for One Mean
When to use: number of variables __________ scaling of variables __________
Basic idea Look at the confidence intervals. Any numbers
in the same confidence intervals are considered the same.
Key question--If my sample mean (xbar) is ___, can my population mean (mu) be ___?
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Hypotheses for T-test for One Mean
Interested in the average number of sodas drunk per day.
Ho: The opposite of Ha: The population mean is equal or (less/greater than or equal to) the the number hypothesized.
Ha: What you need to be actionable. The population mean is (less than/ greater than) _____.
Note: it may be easier to write Ha first.
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Example Ho and Ha
Ho: × = µ Ha: × ≠ µ (two-tailed test)
Ho: X ≥ µ Ha: X < µ (one-tailed test – lower tail)
Ho: X ≤ µ Ha: X > µ (one-tailed test – upper tail)
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Calculations
T calculated = xbar - mustandard error
Where:xbar = sample meanmu = hypothesized population
mean
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More T Calculations
Degrees of freedom=n-1
Alpha level= T-table value =
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Now Graph
t-calculated and t-table value on a normal curve
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Rules for T-test for One Mean
If the calculated t-value is in the hump, ________ Ho. Conclude that your Ha is not correct.
If the calculated t-value is in the tail then _____ Ho. Examine your data to see if Ha or the opposite of Ha is correct.
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Practice Once
Ho: Ha: The populations purchase intention for a
gumball machine is >4.
X-Bar: 4.5 SE= 0.15, n=60 T-calculated Degrees of freedom T-table Graph Conclusion: Reject or Do not Reject Ho Managerial implication:
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Practice Again!
Ho: Ha: The populations purchase intention for a
gumball machine is >4.
X-Bar: 2.3 SE= 0.18, n=60 T-calculated Degrees of freedom T-table Graph Conclusion: Reject or Do not Reject Ho Managerial implication:
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Now Use SAS
Ho: Ha: The average population rating for Coke
when consumers know it is Coke is >6.
T-calculated Degrees of freedom T-table Graph Conclusion: Reject or Do not Reject Ho Managerial implication:
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T-test for Two Means
When to use: Number of variables = _______ One variable (the groups) is _______ scaled One variable (the dependent variable) is
________ scaled Basic idea:
See if the confidence intervals for the two different groups overlap. If they do, then _________________________________ .
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Hypotheses for T-test for Two Means
Is there a difference between the number of sodas males drink per day and the number of sodas females drink per day?
Ho: The two groups are the same with respect to __________ .
Ha: The two groups are different with respect to _______. Specifically, ______________.
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More on T-tests for Two Means No calculations
Check to see if variances are equal or unequal Look at “Equality of Variances” –
Ho: variances are equal Ha: variances are not equal
If p>.05 accept Ho and use equal variances If p<.05 reject Ho and use unequal
variances
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More on T-tests for two means
Check the T-test table to see if you should accept or reject your Ho:
• T-value =(either for equal or unequal variance)
• P-value =
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Rules
If the probability level is ________ 0.05, then ________ Ho. Conclude that the two groups are different. LOOK AT THE DATA TO DETERMINE WHAT THE DIFFERENCE IS.
If the probability level is ______ 0.05, then __________ Ho. Conclude that the two groups are the same.
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Your Turn
Is there a difference in the number of sodas drunk per day between people who drink soda with breakfast, and people who do not?
Nominal variable= ___________ Interval variable = ___________ Ho: Ha: Probability level Conclude--reject or do not reject ho Managerial Implication
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Your Turn again Is there a difference in the number of sodas
drunk per day between people who drink soda with breakfast, and people who do not?
Nominal variable= ___________ Interval variable = ___________ Ho: Ha: Probability level Conclude--reject or do not reject ho Managerial Implication
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ANOVA When to use:
Testing mean differences between groups Have more than 2 groups Want to test interactions between 2 variables
Same as a t-test except that you have more than two groups Number of variables = _______ Some variables (the groups) are _______ scaled One variable (the dependent variable) is ________
scaled
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Ho: all the means are equal
Ha: one of the means differs (specify how the mean differs)
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No Calculations: SAS does this
Use Proc GLMClass: the nominally scaled variable(s)Model: specifies the dependent variable,
the dependent variable and interactions
e.g., class= age; model liking= age;mean = age;
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Interpretation:Dependent variable: liking
Sum ofSource DF Squares Mean
Square
Model 6 93.52 15.59
Error 75 433.02 5.77
Corrected Total 81 526.55
Source F Value Pr>FModel 2.70 0.02
NOTE:to determine significance – check the p value (if p less than .05 reject Ho)
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Do it yourself using SAS
You want to test whether age has an impact on the number of sodas consumed per day
HO:
HA:
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F-calculated Alpha P-value
Conclusion:
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THE END!!!