Research design involves a set of decisions regarding what topic is to be studied, among what population, with what research method, and for what purpose. Chapter 4 of Babbie provides a general introduction to research design. It examines the following issues:

PURPOSES OF RESEARCH (Reasons for a Study)
Three of the most common research purposes are: exploration, description and explanation.

1. Exploration
Much of social research is conducted to explore a topic or to provide a beginning familiarity with that topic. This type of research is typical when a researcher is examining a new interest or when the subject of study is relatively new and unstudied. Exploratory studies are more typically done to:

The main shortcoming of exploratory studies is that they seldom provide satisfactory answers to research questions. They can hint at the answers but cannot provide definite answers because of lack of representativeness.

2. Description
A major purpose of many social scientific studies is to describe situations and events. The researcher observes and then describes what was observed. The chief goals of descriptive research are to provide an accurate profile of a group and to describe a process, mechanism, or relationship. Because of its methodology, scientific descriptions are more accurate and precise than casual descriptions. Examples of descriptive studies are:

  3. Explanation
A researcher has an explanatory purpose if she wishes to know why a certain event happened as opposed to simply describing what happened. The degree of relationship between two variables is of particular concern in explanatory studies.  Explanatory research stresses the determination of causes. The following are examples of explanatory research: Note that research designs can be undertaken for more than one reason.

Learning Check!
Discuss the three purposes for doing research. Describe a study that illustrates each purpose.

Units of analysis are those things we examine in order to create summary descriptions of all such units and to explain differences among them. Units of analysis deals with "what" or "whom" the social researcher aims to observe, describe and explain.

53% of the sample are women.

10% of students do not have a favorite course.

Difference between groups and organizations: The distinction between groups and organizations is rather fuzzy. I think of groups as social and smaller units than organizations. Hence a family would be a group and a corporation would be an organization. In both cases, however, the most important thing to remember is that we are still studying a collectivity of individuals instead of individuals.


Learning Check!
Units of Analysis in Review in Babbie, pages 95-96.

A. Ecological Fallacy: Ecological units refer to groups or sets or systems: something larger than individuals. Ecological fallacy occurs when we assume that something learned about an ecological unit says something about the individuals making up that unit. This fallacy occurs when the observations are gathered at a higher level or aggregated unit of analysis, but the causal explanations being made is about a lower or disaggregated unit. It is always possible that patterns observed at the aggregate level do not reflect behavior at the individual level.

Example: A researcher finds that crime rates are higher in cities having large African American populations than in those with few African Americans. She then concludes that African Americans are more likely to commit crimes than other Americans. Note that we do not know who commits crimes in these cities.

B. Reductionism: Refers to an overly strict limitation on the kinds of concepts and variables to be considered as causes in explaining a broad range of human behavior. Reductionism of any type suggests that particular units of analysis or variables are more relevant than others.

POINTS OF FOCUS: Most social science research concentrates on one of three points of focus: characteristics, orientations, and actions. Learning Check!
Question 7 in Study Guide (page 54).


Approximating Longitudinal Studies from cross-sectional designs: We can approximate conclusions about processes that take place over time, even when only cross-sectional data are available. This can be accomplished in the following ways: Learning Check!

The table below contains census data collected in 1970, 1980, and 1990. Column variables represent the year the data was collected. The rows represent the year that the respondents were born. There are three cohorts in this table: people born in 1930, 1940, and 1950. The cells are labeled A through I. The number within each cell represents the respondents' age at the time of measurement.

Use the table below to identify which cells represent cross-sectional, panel, cohort and trend studies.

Year of Birth (Cohort) 1970 1980 1990
1950 A-20 B-30 C-40
1940 D-30 E-40 F-50
1930 G-40 H-50 I-60

HOW TO DESIGN A RESEARCH PROJECT & THE RESEARCH PROPOSAL: Read these sections of the chapter 4 very carefully. They will help you design your own research project and provide an overview of the topics to be covered for the rest of the semester. Try to understand the various components of a research project.

You may find this site, The structure of Research Paper useful.