Consumer behavior – Core
Summary
Lecture 1
Consumer behavior is:
1. Obtaining
2. Consuming
3. Disposing
Projection bias / false consensus: We overestimate how much other people agree with us.
Confirmation bias: We focus on confirming our beliefs. We are resistant to changing our beliefs.
Self-serving bias: We are likelier to attribute positive aspects to ourselves whilst attributing negative
aspects to external factors.
The study of consumer behavior follows a cycle of the following phases: (ILPDDW)
1. Identification of research problem
2. Literature/study review
3. Problem definition/research plan
4. Data collection
5. Data analysis/interpretation
6. Writing and evaluating the research
Methods of studying are:
1. Surveying / interviewing
2. Experimenting
Avoid self-reports by:
1. Analyzing choices
2. Implicit association test (IAT)
3. Eye tracking
Keep in mind when studying consumer behavior:
Beware of common sense avoid oversimplified/incorrect assumptions
Nature of relationship: causal or correlational?
CB is a social science: reducing uncertainty rather than establishing certainty
Qualitative data is richer, but more costly to analyze
,Lecture 2
Different research strategies in consumer behavior:
Descriptive
o Obtains a snapshot (a description) of specific characteristics of a specific group of
individuals.
o For example: a political poll.
Correlational
o Examine relationship between variables.
o Relationships between variables may be:
Linear
Curvilinear
Positive
Negative
o Relations between variables can be defined in correlation coefficients.
‘+’ indicates a positive correlation.
‘-‘ indicates a negative correlation.
A value between 0.0 and 1.0 indicates the strength of the correlation.
Experimental
o Researchers randomly assign participants into conditions.
o Answers cause-and-effect questions about the relationship between two variables.
Quasi-experimental
o Participants self-assign themselves into conditions.
o Almost, but not quite, experiments – can never produce an unambiguous explanation.
Nonexperimental
o Participants have been assigned into conditions before the start of research (e.g.:
gender).
o Involves two groups of scores and focuses on the difference between groups.
o Demonstrates a relationship between variables – does not attempt to explain it.
Terminology for research:
Independent variable (IV): Variable manipulated by the researcher.
o Levels: Different values or settings of the IV to define treatment conditions.
o Condition: The specific setting influenced by the IV's levels.
Dependent variable (DV): Variable observed to assess effects of the IV's manipulation.
Moderator variable: A variable that influences (strengthens or weakens) an effect between two
other variables. Answers the question: “When does A affect B? Answer: C”.
Mediator variable: A variable that is influenced by one variable, and in turn influences the next.
Answers the question: “How does A affect C? Answer: B”.
Extraneous variables: All variables in the study other than the IV and DV that could affect the
outcome.
Confounding variables: Are outside variables that changes the effect that is being researched. It
can change the outcome of the study and is thus a threat to internal validity.
, Factor: an independent variable (IV) in an experiment (especially experiments that include two or more
IVs).
Factorial design: a research design that includes two or more factors (IVs)
A single-factor design has one IV
A two-factor design has two IVs
A two-factor design with two IVs each one having two levels is called a
2x2 design.
A two-factor design with two IVs one having two levels and the other
one three levels is called a 2x3 design etc.
A 2x3x2 design is a three-factor design with a total of 12 conditions etc.
Graphing the results of a two-factor study:
No interaction Interaction indicated
Note: A statistical test is needed to determine whether the interaction is significant
External validity:
The extent to which the results of a research study can be generalized.
A threat to external validity: Any characteristic of a study that limits the ability to generalize the
study’s results.
Different kinds of generalization can involve threats to external validity:
o Generalization from a sample to the general population.
o Generalization from one research study to another.
o Generalization from a research study to a real-world situation.
Internal validity:
Concerned with factors in the research study that raise doubts or questions about the
interpretation of the results
A research study with internal validity
o Produces a single, unambiguous explanation for the relationship between two variables
Threat to internal validity
o Any factor that allows an alternative explanation for the results
Summary
Lecture 1
Consumer behavior is:
1. Obtaining
2. Consuming
3. Disposing
Projection bias / false consensus: We overestimate how much other people agree with us.
Confirmation bias: We focus on confirming our beliefs. We are resistant to changing our beliefs.
Self-serving bias: We are likelier to attribute positive aspects to ourselves whilst attributing negative
aspects to external factors.
The study of consumer behavior follows a cycle of the following phases: (ILPDDW)
1. Identification of research problem
2. Literature/study review
3. Problem definition/research plan
4. Data collection
5. Data analysis/interpretation
6. Writing and evaluating the research
Methods of studying are:
1. Surveying / interviewing
2. Experimenting
Avoid self-reports by:
1. Analyzing choices
2. Implicit association test (IAT)
3. Eye tracking
Keep in mind when studying consumer behavior:
Beware of common sense avoid oversimplified/incorrect assumptions
Nature of relationship: causal or correlational?
CB is a social science: reducing uncertainty rather than establishing certainty
Qualitative data is richer, but more costly to analyze
,Lecture 2
Different research strategies in consumer behavior:
Descriptive
o Obtains a snapshot (a description) of specific characteristics of a specific group of
individuals.
o For example: a political poll.
Correlational
o Examine relationship between variables.
o Relationships between variables may be:
Linear
Curvilinear
Positive
Negative
o Relations between variables can be defined in correlation coefficients.
‘+’ indicates a positive correlation.
‘-‘ indicates a negative correlation.
A value between 0.0 and 1.0 indicates the strength of the correlation.
Experimental
o Researchers randomly assign participants into conditions.
o Answers cause-and-effect questions about the relationship between two variables.
Quasi-experimental
o Participants self-assign themselves into conditions.
o Almost, but not quite, experiments – can never produce an unambiguous explanation.
Nonexperimental
o Participants have been assigned into conditions before the start of research (e.g.:
gender).
o Involves two groups of scores and focuses on the difference between groups.
o Demonstrates a relationship between variables – does not attempt to explain it.
Terminology for research:
Independent variable (IV): Variable manipulated by the researcher.
o Levels: Different values or settings of the IV to define treatment conditions.
o Condition: The specific setting influenced by the IV's levels.
Dependent variable (DV): Variable observed to assess effects of the IV's manipulation.
Moderator variable: A variable that influences (strengthens or weakens) an effect between two
other variables. Answers the question: “When does A affect B? Answer: C”.
Mediator variable: A variable that is influenced by one variable, and in turn influences the next.
Answers the question: “How does A affect C? Answer: B”.
Extraneous variables: All variables in the study other than the IV and DV that could affect the
outcome.
Confounding variables: Are outside variables that changes the effect that is being researched. It
can change the outcome of the study and is thus a threat to internal validity.
, Factor: an independent variable (IV) in an experiment (especially experiments that include two or more
IVs).
Factorial design: a research design that includes two or more factors (IVs)
A single-factor design has one IV
A two-factor design has two IVs
A two-factor design with two IVs each one having two levels is called a
2x2 design.
A two-factor design with two IVs one having two levels and the other
one three levels is called a 2x3 design etc.
A 2x3x2 design is a three-factor design with a total of 12 conditions etc.
Graphing the results of a two-factor study:
No interaction Interaction indicated
Note: A statistical test is needed to determine whether the interaction is significant
External validity:
The extent to which the results of a research study can be generalized.
A threat to external validity: Any characteristic of a study that limits the ability to generalize the
study’s results.
Different kinds of generalization can involve threats to external validity:
o Generalization from a sample to the general population.
o Generalization from one research study to another.
o Generalization from a research study to a real-world situation.
Internal validity:
Concerned with factors in the research study that raise doubts or questions about the
interpretation of the results
A research study with internal validity
o Produces a single, unambiguous explanation for the relationship between two variables
Threat to internal validity
o Any factor that allows an alternative explanation for the results
