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Marketing research
Lecture 3
Question | Answer |
---|---|
What conditions need to be checked to determine causality? | 1. concomitant variation: extent cause X and an effect Y occur together or vary 2. Time order of occurrence: First X then Y 3. Absence of other possible causal factors: control other factors or hold constant |
Third cause fallacy | Does one cause the other? no there is a third cause |
Experiments | Common way to determine causality |
Types of experiments | - field experiment: implement in one market and not the other - lab experiment : show to one group and not the other |
What can disturb the outcome and solutions? | - other things going on in test markets and other markets - two experimental groups not being similar |
How to eliminate all 'other causes' | - Control for other variable things in analysis - Random assignment to groups |
What're the three main approaches for experimental research? | -true experiment -field experiment -quasi experiment |
What are true experiments? | Can determine causal relationships because the researcher systematically orchestrates a situation so that people in one way or another way. Often performed in a lab. also possible in surveys |
Disadvantages of true experiments | - manipulation makes the situation less like a real world situation - Evaluation apprehension -manipulation is usually between subjects |
within subjects design | The same participant tests all conditions corresponding to a variable |
Between subjects design | different participants are assigned to different conditions corresponding to a variable |
Advantages of field experiments | - setting more similar to real life situation - shoppers in their natural environment - less evaluation apprehension |
Disadvantages of field experiments | - Less experimental control - intervening variables |
Advantages of quasi- experiments | - Natural setting - heterogeneity in respondents - less evaluation apprehension |
Disadvantages of quasi- experiments | - Existing groups, no manipulation - no random assignment - less experimental control |
5 important concepts for regression | 1. Dependent variable Y, Independent variable X 2. Check R squared and ANOVA F for overall diagnostics 3. Check p-values( significance) 4. standardized coefficients 5. including nominal variables |
Explanatory variables in conjoint analysis are often not interval/ ratio but nominal/categorical, so what extra effort is needed? | - If independent variable is yes or no, recode to no=0 and yes=1 (1 is dummy variable) - If its categorical make dummy variable 1 less than there are levels |
Important issue in regression : multicollinearity | - Can't distinguish what causes sales change - hows up by surprising signs and parameters cancel each other |
How to check for multicollinearity | - high correlations in correlation matrix - Variance inflation factor per variable, VIF>5 is suspicious |
New product development | Conjoint analysis as a tool for better decision making |
What're the 3 main conjoint methods? | 1. Conjoint value analysis: respondents rate profiles on a scale 2. Choice based conjoint: choose preferred profile from a set 3. Rank ordering: rank order the profiles |
Choice based conjoint advantage | Greater realism/easier task |
choice based conjoint disadvantages | - less information per individual - Respondents have to understand several profiles at once - linear regression wont work, requires multinomial logit |
Conjoint value analysis | Respondents perform tasks; give evaluation grade of product profile, do this many times for different profiles. Use these grades to infer the utilities of individual attributes |
Conjoint analysis decomposes utility into separate parts | Assumption: product is a bundle of attributes, each attribute has a certain utility for a level. Utilities of these characteristics are computed with linear regression. Show mulitple manipulated products to get enough info |
How to determine the attributes and levels that will be experimented with | - use exploratory research, in house expertise, find the attributes and levels the customers care about - focus on attributes that can be changed - try have attributes have same levels to avoid number of levels effect (many levels seem more important) |
What is orthogonal design? | a way to reduce the number of questions, effects of attributes can be separated |
Which attribute level do you leave out? | The estimate of the levels indicate the change in rate relative to the one left out |
Which attribute is most important? | importance is calculated from the range of betas ( betamax- betamin). could also compute importance per segment. |
Benefits of conjoint analysis | -Estimate preference quantitatively instead of direct questioning and guessing -See which attribute levels are valued highly - focus on these in product development |
limitations of conjoint analysis | - all features cannot be incorporated -many observations needed - is utility really compensatory - answering more than 9 questions can be taxing - respondents don't have to live with their choice - metric conjoint |