1. EDU702 Research Methodology Quantitative Research
Prepared by
Azurawati Binti Wok Zaki
ED7701A2

2. Chapter 16: Causal-Comparative Research
(Ex post facto Research
Non-experimental research)

3. THE AIM
to determine the cause of existing differences among groups.

4. Causal-Comparative Research is Differentiated from Experimental Research
In an experiment, the independent variable is manipulated by the researcher.
In causal comparative research the independent has already occurred.
Examples of independent variables include socioeconomic status, pre-school history, number of siblings, and so on.

5. Three types of causal-comparative research
Exploration of effects (dependent variable) cause by membership in a given group
Question: What differences in abilities are caused by gender?
Research hypothesis: Females have a greater amount of linguistic ability than males.
Type 2
Exploration of causes (independent variable) of group membership
Question: What causes individuals to join a gang?
Research hypothesis: Individuals who are members of gangs have more aggressive personalities than individuals who are not members of gangs.
Type 3
Exploration of the consequences (dependent variable) of an intervention
Question: How do students taught by the inquiry method react to propaganda?
Research hypothesis: Students who were taught by the inquiry method are more critical of propaganda than are those who were taught by the lecture method.
An independent variable is the variable which you change in an experiment. Note you can only have 1 variable that can change in an experiment and more than one independent variable will result in an unfair experiment. 
A dependent variable is the measure of the independent variable. Therefore it depends on the independent variable. 
Weight depends on the amount of food (in calories) we eat. The more we eat, the more weight we gain. Weight is the dependent variable. The amount we eat is the independent variable.

6. Causal- comparative and Correlational Research
Similarities:
researchers explore relationship among variables
seek identify variables that are worthy of later exploration through experimental research.
provide guidance for subsequent experimental studies.
attempt to explore causation

7. Differences: Causal-Comparative vs Correlational
- Compare 2 or more groups of subjects
- Require a score on each variable for each subject.
Involve at least one categorical variables (group membership)
- Investigate 2 (or more) quantitative variables
- Often compare averages or use crossbreak tables.
- Analyse data using scatterplots

8. Causal-comparative and Experimental Research
Similarities:
- Require at least one categorical variable (group membership).
- Compare group performances (average score) to determine relationship.
- Both typically compare separate group of subjects.

9. Differences: Causal-Comparative vs Experimental
- No manipulation takes place
- Independent variable is manipulated
- Provide much weaker evidence for causation than do experimental studies.
- The group are already formed (the researcher must locate them)
- The researcher can assign subjects to treatment groups
- The researcher has much greater flexibility in formulating the structure of the design.

10. Value of Causal Comparative Research
Uncovers relationships to be investigated experimentally.
Used to establish cause-effect when experimental design not possible.
Less expensive and time consuming than experimental research.
Note: if you conduct a quantitative research study it most likely will be a causal-comparative study.
Used to establish cause-effect when experimental design not possible for legal, physical, ethical, or financial reasons
Example: effects of smoking on health (even if ethical, might take 15 yrs to get answer and we might not want to wait)

11. More Examples of Causal Comparative Research
A researcher measured the mathematical reasoning ability of young children who had enrolled in Montessori schools and compared the scores with a group of similar children who had not been to Montessori schools.
A researcher measured the frequency of students’ misbehavior at schools which use corporal punishment and compared that to schools which did not use corporal punishment.

12. More Examples of Causal Comparative Research
A researcher compared the high school dropout rate between students who had been retained (held back) in elementary school vs. similar students who had not been retained
A researcher formed 3 groups of preschoolers – those who never watched Sesame Street, those who watched it sometimes, and those who watched it frequently – and then compared the 3 groups on a reading readiness test

13. How does having a working mother affect a child’s school absenteeism?
More Examples:
How does preschool attendance affect social maturity at the end of the first grade?
How does having a working mother affect a child’s school absenteeism?
How does preschool attendance affect social maturity at the end of the first grade? The grouping variable is preschool attendance (i.e.; the variable can take one of the two values students attending preschool and student not attending).the dependent variable or effect is social maturity at the end of the first grade. The research identifies the group of first grade who attend the preschool and a group who did not, gathers data about their social maturity, and then compares the two groups.
How does having a working mother affect a child’s school absenteeism? The grouping variable is the employment status of mother(again with 2 possible values the mother work or mother does not work); the dependent variable is absenteeism, measured as number of day absent. The researcher identifies the group of students who have working mother and group whose mother don’t work, gather information about their absenteeism and compares the groups.

14. STEPS TAKEN 1) Problem Formulation 2) Sample 3) Instrumentation
4) Design
STEPS TAKEN

15. Threats Subject Characteristics - Matching the subjects
- Finding or Creating Homogeneous Subgroups
- Statistical Matching

16. Data Analysis in Causal-Comparative Studies
To construct frequency polygon
Means and standard deviations are usually calculated in the variables involved are quantitative.
The most used test is a t-test for differences between means.
Analysis of covariance is useful.
The results should always be interpreted with caution.

17. Chapter 17: Survey Research
The most popular technique for gathering primary data in which a researcher interacts with people to obtain facts, opinions,
and attitudes.

18. The Purpose of Survey Research
To describe the characteristics of a population
To find out how the members of a population distribute themselves on one or more variables
Rarely is the population as whole studies, however. Instead, a sample is surveyed and a description of the population is inferred from what the sample reveals.

19. The main way- asking questions
3 Characteristics
Information is collected from a group of people in order to describe some aspects of characteristics of the population of which that group is a part.
The main way- asking questions
Information is collected from a sample rather than from every member of the population.

20. Types of Surveys i) Cross-sectional study
A study in which various segments of a population are sampled. E.g. managers and non-managers.
Data are collected at a single moment in time.
When an entire population is surveyed: Census

21. example
A professor of Mathematics might collect data from a sample of all the high school mathematics teachers in a particular state about their interests in earning a master’s degree in Mathematics from his university.

22. ii) Longitudinal study
Longitudinal survey
- information is collected at different points in time in order to study changes over time.

23. 3 Longitudinal designs Trend study Cohort Study
Panel Study
different samples from a population whose member may change are surveyed at different points in time.
a particular population whose members do not change over the course of the survey.
the researcher surveys the same sample of individuals at different times during the course of the survey.

24. Examples:
Trend study:
- A researcher might be interested in the attitudes of high school principals towards the use of flexible scheduling. He would select a sample each year from a current listing of high school principals throughout the year. The same individual would not be the sampled each year, he would compare responses from year to year to see whether any trends were apparent.

25. Cohort study
A researcher would like to study growth in teaching effectiveness of all the 1st year teachers who had graduated in the past 5 years from a university. The names of all would be listed, and different sample would be selected from this listing at different times.

26. Panel study
A researcher select a sample of last year’s graduates from a university who are 1st year teachers and survey on the same individual several times during the teaching years.

27. Identifying the target population
Steps taken
Defining the problem
- It should be interesting and important to motivate individuals to respond.
Identifying the target population

28. Forms of Survey Research
Chapter 7
Decision Support Systems and Marketing Research
Forms of Survey Research
Mail Surveys
Internet surveys
Telephone surveys
Personal Interviews
On Line: Hershey
Go to Hershey’s and read its Idea Submission Policy under Consumer Info. Do you think the policy is a good idea?
Notes:
In home personal interviews: Provide high-quality information, but are expensive because of travel time and mileage costs for the interviewer. Not a popular survey tool.
Mall Intercept interviews: Conducted in shopping malls or in a marketing research office in the mall. Surveys must be brief. It is hard to get a representative sample of the population.
Telephone interviews: Cost less and provide one of the best samples of any traditional survey procedure. Many facilities for telephone interviews utilize computer-assisted interviewing, where information is directly input into a computer application.
Mail Surveys: Benefits are low cost, elimination of interviews, centralized control, and anonymity for respondents. However, mail questionnaires usually produce low response rates.
Executive interviews: Survey involves businesspeople at their offices regarding industrial products or services. This type of interviewing is expensive, due to the process of finding, qualifying, and interviewing respondents.
Focus groups: A type of personal interviewing, characterized by seven to ten people gathered in a meeting place. The interaction provides group dynamics, with an interplay of responses yielding richer information than individual interviews.

29. COMPARISON OF SURVEY TECHNIQUES
Chapter 7
Decision Support Systems and Marketing Research
Comparison of three kinds of surveys
Marketing researchers must be aware of the trade-offs when collecting primary data through the three main types of questionnaires.

30. Advantages and Disadvantages
Direct Administration
Tele-phone
Mail
Inter-view
Comparative Cost
Lowest
Inter-mediate
High
Facilities needed?
Yes No
Require training of questioner?
Data collection time
Shortest
Short
Longer
Longest
Response rate
Very high
Good
Poorest
Very High
Group administration possible
Allow for random sampling?
Possibly
Require literate sample?
Permit follow-up-questions?
Encourage response to sensitive topics?
Somewhat
Weak
Standardization of responses
Easy
Hardest

31. Questionnaire Design Open-Ended Question Closed-Ended
Chapter 7
Decision Support Systems and Marketing Research
Questionnaire Design
Open-Ended
Question
Closed-Ended
An interview question that encourages an answer phrased in respondent’s own words.
An interview question that asks
the respondent to make a selection from a limited list of responses.
Notes:
Questionnaires contain three basic types of questions:
Open-ended questions
Closed-ended questions
Scaled-response questions.
Examples of these types of questions are shown on the next slide and in Exhibit 7.5.

32. Advantages Disadvantages Closed-ended Open-ended
-Enhance consistency of response across respondents
- Allow more freedom of response
-Easier and faster to tabulate
- Easier to construct
- More popular with respondents
- Permit follow-up by interviewer
Disadvantages
- May limit breadth of response
- Tend to produce responses that are consistent in length and content across respondents
- Take more time to construct
- Both questions and responses subjects to misinterpretation
- Require more questions to cover the research topic
- Harder to tabulate and synthesize

33. TYPICAL PROBLEMS IN WORDING QUESTIONS
Chapter 7
TYPICAL PROBLEMS IN WORDING QUESTIONS
Decision Support Systems and Marketing Research
Typical problems in wording questions

34. Respondent Error
A classification of sample bias resulting from some respondent action
Non-response
-Total Nonresponse

35. Non-response -total nonresponse
Not enough people respond or refuse to respond
NONRESPONDENTS - People who refuse to cooperate
NOT-AT-HOMES
SELF-SELECTION BIAS especially in case of self-administered questionnaire. People respond to only those they like.

36. Item Nonresponse
The respondent may not know the answer to a particular question, the respondent may find the questions embarrassing or irrelevant.

37. The END
Thank You