Session6 - Duke University`s Fuqua School of Business
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Transcript Session6 - Duke University`s Fuqua School of Business
Questionnaire Design, Survey Methods,
Sampling and Causal Research
Market Intelligence
Julie Edell Britton
Session 5
September 4, 2009
1
Today’s Agenda
Announcements
Comparative Advertising, Measurement
Scales & Data Analysis
Introduction to Survey Research
Sampling Procedures
Causal Research - maybe
2
Announcements
For Sat prepare Milan Food case – download
data (Milan.sav) from the platform, please
post your responses by 8 pm tonight – no
slides needed.
For Sat prepare WSJ/ Harris Survey – no
slides
3
Comparative Advertising Measurement
Scales & Data Analysis
Page 52 packet
What do you conclude?
Remember – Percentage change or
difference can only be calculated with Ratio
scales
This is an interval scale (at best).
4
Descriptive Survey Research
Surveys usually used for descriptive research
Provide a snapshot at a point in time
Most analyses univariate or bivariate (but can do
elaboration model with control variables)
Would you recommend National to a friend interested in
insurance services? Yes 1 No 2
Bivariate allows for hypothesis testing
Hypothesis: Less educated people more likely to recommend
Descriptive, not causal
Recommendation could be driven by some 3rd factor
correlated with education such as income
5
Sources of Survey Errors
Population definition
Representativeness of the sample frame
Sampling Procedure Used
Respondent Participation:
Willing to participate (Do Not Call)
Comprehend questions
Have knowledge, opinions
Willing & able to respond (language or memory)
Interviewer understands & records accurately
6
Raising Willingness to
Participate
A good response rate requires persuasion
Survey Introduction
Phone or send letter in advance
Introduce self, give affiliation unless this would
bias
Describe purpose briefly, w/o making survey
sound threatening or demanding
Make respondent feel that s/he is getting chance
to provide opinions that will influence market
offerings & that her/his cooperation is extremely
important
7
Comprehends Questions?
Advice on Question Wording
Be simple and precise
Give clear instructions
Check for question applicability
respondent screening
question branching based on prior
answers
Avoid leading & double barrel questions
8
What’s the Problem?
“Laws should be passed to eliminate the
possibilities of special interests giving huge sums
of money to candidates”
“Laws should be passed to prohibit interest groups
from contributing to campaigns, as groups do not
have the right to contribute to candidates they
support?”
9
Comprehends Questions?
Literacy, translation considerations
Conversational Norms
How demanding was Term 3? How demanding was
Core Finance?
How demanding was Core Finance? How
demanding was Term 3?
How demanding was Managerial Accounting? How
demanding was Core Finance? How demanding was
Global Economic Environment of the Firm? How
demanding was Term 3?
“Question order effects in measuring service quality,” by DeMoranville and Bienstock,
in International Journal of Research in Marketing, September, 2003
10
Do Respondents Have Knowledge?
Retrieve answer from memory vs. construct it on spot
Constructed answers are more likely to be influenced by
question wording & prior questions.
When answering later questions or engaging in later behavior,
likelihood of using earlier answer input A:
positively related to accessibility of A
positively related to diagnosticity (relevance) of A
negatively related to accessibility, diagnosticity of alternative inputs B, C,
etc. (Feldman & Lynch)
e.g., when political poll respondents asked:
issue opinion A, presidential voting intention, issue opinion B,
answers to A predict intention, but only for those who did not vote for either
candidate in primary
11
Survey Best Practices:
Survey Content, Question Order
Survey Questions
First figure out what questions are needed!
Then order
Lead with interesting, nonthreatening, easy questions
Do you like to play golf?
Have you ever travelled with your clubs?
Can you remember the last time you traveled with your clubs?
Put difficult or sensitive questions well into the interview
How many times did you have to see your doctor for your
reconstructive surgery?
What is the size of your company (revenue)?
Usually use funnel order (general to specific)
Use product category?
Brand X?
Do you like Brand X?
Why?
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12
Question Order (Cont.)
Survey Questions (cont.)
Inverted funnel (specific to general) for complex topics.
Is your company considering offering training courses on word
processing over the Internet?
Database? Spreadsheets?
In general, how big is the untapped market for your software
training courses if offered over the Internet?
Group questions in logical order
All questions about one subject together, with transitional
phrases in between, “Now I’m going to ask you about agricultural
applications of GPS systems...”
13
Survey Best Practices:
Question Order (cont.)
Demographics Questions
Put last—these are less sensitive to prior questions
Seem nosy if put first
Rely on standard approaches for assessing
http://www.norc.org/GSS+Website/
The Process of Survey Design
Use Backwards Marketing Research to decide what is
“need to know”
Draft the survey
Pretest for time, clarity, variability in responses
Revise and retest
Field the survey and keep an eye open for problems
14
15
Survey Best Practices:
Choosing a Survey Method
Mail, phone, web, in person?
Cost
Complexity of inquiries (branching)
Need for aids
Issue sensitivity
Control over sample
16
Web and Telephone
Web surveys now dominate. To compare web,
in person, phone, mail, see
http://knowledge-base.supersurvey.com/
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17
Free to Fuqua students: Qualtrics
http://www.qualtrics.com/duke#submit
Set up an account
Build surveys
Allows for complex designs
Available to you during this course
18
Multi-Attribute Attitude Model
(MAAM)
Liking for a product as a whole = sum of liking for
component parts
Attitude toward brand j = (sum from i = 1 to n for
salient attributes)
Importance of Attributei * Evaluationij
Importance
0 – 100 (allocate 100 points across attributes)
Rating on 1 (unimportant) to 7 (very important) where 0
undefined but implicitly entirely unimportant )
Evaluation of brand j on attribute I
-4 = poor to +4 = excellent
19
MAAM and SUVs
Attribute
Sporty Styling
Handling
Cost
Ruggedness
Off-Road Ability
Total Attitude
Importance
1=unimp,
7= important
6
5
2
4
2
Land
Rover
RAV
Land Rover
RAV
Brand Evaluation
-4 = poor, +4 =
excellent
Imp*Eval Imp*Eval
1
2
6
12
0
1
0
5
-2
3
-4
6
4
2
16
8
2
4
4
8
22
39
20
Diagnostics of Advantage
21
Measure Types Revisited
Nominal (Unordered Categories)
Just need unique number for each category
Ordinal: ranking scale, intervals not assumed equal
Interval: Intervals assumed equal, zero is arbitrary
Ratio: Intervals assumed equal, zero means zero
To multiply X * Y, (e.g., importance * evaluation), both X and Y must
be on ratio scales.
If X1*Y1 > X2*Y2 (XYbrand 1 >XYbrand 2), it does NOT follow that
(X1+a)*Y1 > (X1+a)*Y2….
e.g., 2*2 > 2*(-2), but (2-4)*2 < (2-4)*(-2)
To say % change in Y, Y must be on ratio scales
22
More on Scaling
To multiply importance x evaluation for each
attribute, both must be on ratio scales
0 on scale must be 0 of underlying quantity
Importance unipolar (all positive). Completely
unimportant = 0 weight
Evaluation bipolar (negative to positive). To
multiply, must code “neutral” as zero.
23
Improper Rescaling
Attribute
Sporty Styling
Handling
Cost
Ruggedness
Off-Road Ability
Total Attitude
Importance
-3 =unimp,
+3 = imp
2
1
-2
0
-2
Land
Rover
RAV
Evaluation -4 =
poor, +4 =
excellent
1
0
-2
4
2
Land Rover
Imp*Eval
2
1
3
2
4
RAV
Imp*Eval
2
0
4
0
-4
2
Diff
4
1
-6
0
-8
-9
2
1
-10
0
-4
-11
I got these by subtracting 4 from the values three slides back
24
Consumer Attitudes
We want to be able to predict consumer behavior
However, instead of examining behavior directly (e.g.,
choice modeling), we often measure attitudes
because…
Measuring attitudes is sometimes easier than observing
choice
Attitudes are more diagnostic
Attitudes are sometimes easier to interpret
Attitudes can be reasonable predictors of behavior
Attitudes toward products or brands typically derive
from beliefs, actions, and perceptions
25
Types of Attitude Scales
Semantic differential
Colgate Combo is:
low quality
unappealing __:__:__:__:__:__:__ appealing
__:__:__:__:__:__:__ high quality
Constant sum (e.g., Importance)
Purchase intent
Likert scale (Agree-Disagree)
26
Recap
Survey Design: responses constructed on the spot
Moving parts of a good survey Population definition,
choosing a survey method, determining what information
needed
Order of questions
Attitude Measurement & multi-attribute attitude model
To multiply or examine percentage differences, data
must be on ratio scales
27
Sampling Terminology
Elements -- Units about which information is sought
Population -- Elements we want to generalize to
Census -- Collect data on all elements in population
Sampling Frame -- At each stage, list of all
elements
Sample – Collect data on subset of elements in pop.
28
Sampling Process
Define population
Elements, extent, time
Identify a good sampling frame
costly to create for yourself
Determine sample size
budget, accuracy needs
Select sampling procedure
way to select elements from the frame
Physically select sample
29
Probability Samples
Each element in population has known, nonzero chance of
being sampled
Simple random sample: all elements have 1/n chance of
being sampled (e.g., cold caller)
Systematic sample: start with randomly selected element
and take every nth element (e.g., teams in this class)
Cluster sampling: pick groups of elements (city blocks,
census tracts, schools) then randomly select n elements from
each cluster
Stratified sampling: divide frame into strata according to a
characteristic (e.g., gender), then sample randomly from
each strata
30
Complex Sampling Procedures
Simple random sampling almost never
used in practice
Stratified Sampling -- Lowers error
Cluster Sampling -- Lowers cost of
getting frames and of data collection
31
Stratified Random Sample
Have frames sorted on some stratification
variable believed to influence the variable
you are estimating.
Lower variance within each subgroup than
across population in general
By ensuring that each subgroup is
represented in right mix, extreme overall
means less likely -- i.e., smaller std. error.
32
Steps for Stratified Random Sample
Divide Population into mutually exclusive and
exhaustive categories.
Decide what sampling fraction f = n / N to
use.
Draw an independent simple random sample
of size f * N(stratum) from each stratum.
Compute stratum mean for each
Estimate overall pop mean as weighted
average of stratum means
Estimate SE as weighted combo of SEs in
each
33
Cluster Sampling
Typically “clusters” are geographic territories.
Start with list of clusters, randomly select
subset, and survey only subset.
Cheaper travel cost, cost per interview
Loss of effective sample size if people in
cluster more alike than if in different cluster
34
Non-Probability Samples
Convenience
Judgment
Pick especially informative elements
Quota
Sample matches population on key control
characteristics correlated with behavior under
study.
Match only really matters for control variables
related to thing you are trying to estimate.
35
Sampling quiz:
Proportion of WEMBA students interested in
changing jobs? Sample of 50
How would you do:
Convenience Sample
Judgment
Quota sample (by male / female)
Simple random
Systematic
Stratified (by male / female)
36
Key Sampling Takeaways
Probability v Non-Probability Samples
For Probability Samples, Standard Error is
the measure of precision
Precision increases with square root of N
More precision with Stratified if and only if
stratifier is correlated with thing estimated
Same principal for Quota samples. Quotas
only help if correlated with variable
37
Experiments
Best way to test causal hypotheses
Independent Variable = hypothesized cause
Manipulated by the researcher/manager
Example: Send a color or black and white
brochure
Dependent Variable = effect
Measured (observed) by researcher/manager
Example: New accounts secured
Random assignment of subjects to conditions
Example: receive color or receive b&w brochure
38
Pre-experimental Designs
One group, after-only design
One group, before & after design
Unmatched control group design
Matched control group design
All have threats to validity not present in a
true experiment with random assignment
to treatments.
39
Validity
The strength of our conclusions
i.e., Is what we conclude from our experiment correct?
Threats to Validity
History: an event occurring around same time as treatment
that has nothing to do with treatment
Maturation: people change pre to post
Testing: pretest causes change in response
Instrumentation: measures changed meaning
Statistical Regression: Original measure was due to a
random peak (SI Cover Curse) or valley
40
One Group After Only
We propose a change in MBA Core, to move Finance
and Marketing up to Term 2 from their position in Term
3. One major motive for this is that students interview
for internships in Term 3, and if they want jobs in
marketing or finance, they have no background at the
time of the interview. Thus, we perceive that we are at
a competitive disadvantage because those courses
are in Term 3.
EG
X
O (Mean = 50%)
X = Marketing Term 3, O = Did/Did Not Get Desired Internship
Key: Lacks a baseline, so worthless.
41
One Group Pre-Post Design
Breckenridge Brewery wants to assess the efficacy of
TV ad spots for its new amber ale.
Time 1 (O1): Duke undergrads are brought to the lab
and asked to rate their frequency of buying a series of
brands in various categories over the past week. The
list includes Breckenridge Amber Ale. Mean = 0.2
packs per week.
Time 2 (X): Two weeks of ads for Breckenridge Ale.
Time 3 (O2): Same Duke undergrads brought back to
lab to rate frequency of buying same set of brands over
past week. Mean = 1.3 packs per week.
1.3 - 0.2 = 1.1. We attribute an increase of 1.1 packs
per week to the ad.
42
Online Investor Performance
X = brick and mortar brokerage
customer moves online to trade in 1999
O = Annualized turnover
1998 – 40% annualized turnover
2000 – 100% annualized turnover
Did going online cause people to trade
more actively?
Threats with one-group pre-post?
43
Quasi-Experimental Designs:
Interrupted Time Series
Same as one-group pretest posttest, but
observations at many points in time before
and after key treatment for same people:
EG O1 O2 O3 X O4 O5 O6
Extra time periods help control for history,
maturation, testing. “Quasi-experiment”
44
Online Investor Performance
Gross Returns
10
Net Returns
5
36
33
30
27
24
21
18
15
12
9
6
3
0
-3
-6
-9
-12
-15
-18
-21
-24
-27
-30
-33
0
-36
Cumulative Market Adjusted Return (%)
15
-5
-10
Event Month (0 = month of first online trade)
45
Portfolio Turnover
120%
Size-Matched
100%
Online
80%
60%
40%
20%
24
21
18
15
12
9
6
3
0
-3
-6
-9
-1
2
-1
5
-1
8
-2
1
0%
-2
4
Annualized Turnover (%)
140%
Event Month (0 is month of first online trade)
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2 Groups: Unmatched Control Group
(Effect of Prior Knowledge on Search)
Hypothesis: People with little knowledge about cars search
less online because they are overwhelmed
100 Durham residents who are in the market for a car
EG
CG
X1 (Auto Shop Course) O1 (6 hrs online)
--------------------------------------------------------X2 (Electronics Course) O2 (3 hrs online)
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2 Groups: Matched Control Group
(True Experiment)
EG
R X1 (Auto Shop Course) O1 (6 hrs)
---------------------------------------------------------
CG
R X2 (Electronics Course) O2 (3 hrs)
Control for Selection Threat.
Key Point:
For causal research, chance (not respondent) must
determine respondent assignment to condition.
48
Breckenridge Brewery Ads
Breckenridge Brewery wants to assess the efficacy of TV
ad spots for its new amber ale.
Time 1 (O1): Duke undergrads are brought to the lab
and asked to rate their frequency of buying a series of
brands in various categories over the past week. The list
includes Breckenridge Amber Ale. Mean = 0.2 packs per
week.
Time 2 (X): Two weeks of ads for Breckenridge Ale.
Time 3 (O2): Same Duke undergrads brought back to lab
to rate frequency of buying same set of brands over past
week. Mean = 1.3 packs per week.
1.3 - 0.2 = 1.1 increase in number of packs per week.
49
2-group Before-After Design
• Now add a randomly assigned “Control”
group with mean scores O1 = 0.3, O2 = 0.5.
Experimental
O1 X O2
Control
O1
O2
O1
O2
O2 - O1
Difference
0.2
1.3
1.1
0.3
0.5
0.2
50
Factorial Designs
Independent Variable:
Factor manipulated by the researcher
Dependent Variable:
Effect or response measured by researcher
Factorial Design:
2 or more independent variables, each with two or
more levels.
All possible combinations of levels of A & levels of
B.
51
Oreo Promotion Experiment
Kroger: Supporting a discount on Oreo
cookies
Factor A: Ads in local paper
a1 = no ads
a2 = ad in Thursday local paper
Factor B: Display location
b1 = regular shelf
b2 = end aisle
52
Oreo Promotion Experiment
(Expenditures/customer/2 wks)
a1 = no ads
a2 = ads
Row Ave
b1 =
regular shelf
.60
.90
.75
b2 =
end aisle
.85
.95
.90
Col. Ave
.725
.925
53
Sales of Oreos on Promotion as function of
Local Advertising, Display Location
54
Oreo Example, No Interaction
Main Effect of A (Ads)?
Main Effect of B (Display Location)?
No AxB (say A by B) interaction. Effect of
changing A (Ads) is independent of level of
B (Display Location). Sales go up by $0.30
when you advertise, regardless of location.
Implies that Ad & Display decisions can be
decoupled…they influence sales additively.
55
Managerial Implications of
Interactions
If two controllable marketing decision
variables interact (e.g., advertising x display),
implication is that you can’t decouple
decisions; must coordinate.
If A is a controllable decision variable and B is
a potential segmentation variable (e.g., ads x
urban/suburban), interaction means that
segments respond differently to this lever.
56
Interactions and segmentation
c
Coupons have a bigger effect in the suburbs
Psychology of Consumers
Exposure, Attention, & Perception
57
Takeaways for the Day
Survey Design: responses constructed on the spot?
Order of questions
Attitude Measurement & multiattribute attitude model
Probability v Non-Probability Samples
More precision with Stratified if and only if stratifier is
correlated with thing estimated
Threats to validity in pre-experimental and quasiexperimental designs
Factorial Designs – Main effects and interactions
2 marketing tactics interact coordinate
Marketing tactic interacts with customer classification
implies classification a potential basis for
segmentation…different sensitivities to some marketing
mix variable
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