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Chapter 3:

1. Chapter 3:. General Issues in Research Design. 2. Introduction . As social scientists, we seek to explain the causes of some phenomenon (e.g., crime) Physical growth in plants is caused by a # of factors

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Chapter 3:

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  1. 1 Chapter 3: General Issues in Research Design

  2. 2 Introduction • As social scientists, we seek to explain the causes of some phenomenon (e.g., crime) • Physical growth in plants is caused by a # of factors • Human behavior is much more complex; free will and deterministic constraints affect behavior • Certain factors make some more or less likely to engage in crime

  3. 3 Reasons have Reasons • What causes juvenile delinquency? • Deterministic constraints – lack of parental supervision, peer group association, early childhood experiences, amount/kind of education • Free will aspects – why didn’t you personally choose to hang out with troublemakers? Why didn’t you decide to slack off in school?

  4. 4 So how can we study behavior? • When conducting explanatory social science research, we subscribe to the deterministic camp • We assume that people have little freedom of choice • We do not assume that all human actions are determined, nor that we are all controlled by the same forces, nor that we can find all answers

  5. 5 Probabilistic Causal Model • Certain factors make crime/delinquency more or less likely within groups of people • Two models of explanation • Ideographic – lists the many, perhaps unique, considerations behind an action • Nomothetic – lists the most important (and fewest) considerations/variables that best explain general patterns of cause and effect

  6. 6 Criteria for Causality • Posited by Shadish, Cook, & Campbell (2002) • Empirical relationship between variables • Temporal order (cause precedes effect) • No alternative explanations – no spurious other variable(s) affecting the initial relationship

  7. 7 Necessary and Sufficient Causes • Within the probabilistic model, two types: • Necessary cause – represents a condition that must be present for the effect to occur (being charged before being convicted) • Sufficient cause – represents a condition that, if it is present, will pretty much guarantee that the effect will occur (pleading guilty before being convicted)

  8. 8 Validity and Causal Inference • When we make a cause-and-effect statement, we are concerned with its validity – whether it is true and valid • Certain threats to the validity of our inference exist • These are reasons why we might be incorrect in stating that some cause produces some effect

  9. 9 Statistical Conclusion Validity • Is there is a statistical relationship between the change in the suspected cause and the change in the suspected effect; that is, is there covariation? • Relationship between drug use and crime – if users and nonusers commit the same amount, this demonstrates no statistical relationship (caveats) • Also, when the sample on which the conclusion is drawn is too small, this threatens SCV

  10. 10 Internal Validity • Generally due to non-random or systemic error • The threat to IV results when the relationship between two variables arises from the effect of some third variable • Example: ice cream sales and homicide • Example: drug users sentenced to probation over prison recidivate less

  11. 11 External Validity • Concerned with whether research findings in one study can be replicated in another study • Do the findings apply equally in different settings (locales, cities, populations)? • May also refer to the applicability of experimental research under controlled conditions to the “real world” • POPN experiment, MN Domestic Violence experiment

  12. 12 Construct Validity • Concerned with how well an observed relationship between variables represents the causal process • Are the variables and methods we select sufficient indicators of the underlying social phenomena we wish to observe? Do they square with reality? • Are we measuring what we want to measure or what we claim we are measuring? • e.g., close supervision of officers -> more tickets? • e.g., KC experiment, “police visibility”

  13. 13 Bias and Generalizability • The four types of validity threats can be grouped into these two categories • Bias – IV and SCV threats are related to systematic and nonsystematic bias • CV and EV are concerned with generalization to real-world behaviors and conditions

  14. 14 Does Drug Use Cause Crime? • Temporal order: which comes first? • A statistical relationship exists, but underlying causes affect both drug use and crime (IV threat) • What constitutes drug use? Crime? (CV threat) • How will policy affect drug use and crime? A crackdown on all drugs among all populations will do little to reduce serious crime.

  15. 15 Units of Analysis • What or who is studied • Individuals - (police, victims, defendants, inmates, gang members, burglars) • Groups - multiple persons with same characteristics - (gangs, police beats, patrol districts, households, city blocks, cities, counties) • Organizations - formal groups w/established leaders and rules - (prisons, police departments, courtrooms, drug treatment facilities, businesses, agencies) • Social artifacts - products of social beings and their behavior - (stories in newspapers, posts on the Internet, photographs of crime scenes, incident reports, police/citizen interactions)

  16. 16 Errors of Reasoning • People often make errors in assessing causation • Seek to identify faulty causal reasoning in media sound bytes, editorials, other articles

  17. "The only policy that effectively reduces public shootings is right-to-carry laws. Allowing citizens to carry concealed handguns reduces violent crime. In the 31 states that have passed right-to-carry laws since the mid-1980s, the number of multiple-victim public shootings and other violent crimes has dropped dramatically. Murders fell by 7.65%, rapes by 5.2%, aggravated assaults by 7%, and robberies by 3%." Source: "The Media Campaign Against Gun Ownership", The Phyllis Schlafly Report, Vol. 33, No. 11, June 2000. "…[E]vidence shows that even state and local handgun control laws work. For example, in 1974 Massachusetts passed the Bartley-Fox Law, which requires a special license to carry a handgun outside the home or business. The law is supported by a mandatory prison sentence. Studies by Glenn Pierce and William Bowers of Northeastern University documented that after the law was passed handgun homicides in Massachusetts fell 50% and the number of armed robberies dropped 35%." Source: "Fact Card", Handgun Control, Inc. 17

  18. 18 Issues of Logic • Ecological fallacy - danger of making assertions about individuals based on the examination of groups or aggregations (Poor areas = more crime, therefore poor people commit more crime) • Individual fallacy – using anecdotal evidence to make an argument (O.J. Simpson court resources) • Reductionism - failing to see the myriad of possible factors causing the situation being studied

  19. 19 The Time Dimension • Time sequence is critical in determining causation • Time is also involved in the generalizability of research findings • Observations can either be made more or less at one point, or stretched over a longer period

  20. 20 Cross-Sectional Studies • Observing a single point in time (cross-section); simple and least costly way to conduct research • We cannot see social processes or changes; have to worry if we picked a bad point in time to capture • Typically descriptive or exploratory in nature

  21. 21 Longitudinal Studies • Permit observations over time • Trend – those that study changes within some general population over time (UCR) • Cohort – examine more specific populations as they change over time (Wolfgang study) • Panel – similar to trend or cohort, but the same set of people is interviewed on two or more occasions (NCVS) (panel attrition)

  22. 22 Approximating Longitudinal Studies • May be possible to draw approximate conclusions about processes that take place over time, even when only CS data is available • When time order of variables is clear, logical inferences can be made about processes taking place over time

  23. 23 Retrospective Research • Asks people to recall their past for the purpose of approximating observations over time • People have faulty memories; people lie • Analysis of past records also suffer from problems – records may be unavailable, incomplete, or inaccurate • Prospective research – longitudinal study that follows subjects forward in time (Widom – child abuse/drug use)

  24. 24 Time Dimension Summarized • Cross-sectional study = snapshot – an image at one point in time • Trend study = slide show – a series of snapshots in sequence over time, allows us to tell how some indicator varies over time • Panel study = motion picture – gives information about individual observations over time

  25. 25 How to Design a Research Project • Beginning points for a line of research • e.g., interests, ideas, theories, new programs • Why does something occur? • Why is this how it is? • What about this possible program? • These questions may lead to others you might like to explore

  26. 26 Getting Started • Find out what research has been done • Read newspaper stories, journal articles, check out the Internet, talk to relevant people • Figure out your objective & intended audience • Generally, your purpose for undertaking research can be expressed in a report

  27. 27 Conceptualization • What do you mean by the concept being studied? • If you are going to study fear of violent crime: • What is considered “violent crime”? • What is considered “fear”? • You need to specify ALL the concepts you wish to study

  28. 28 Choice of Research Method • A variety are available, each has strengths and weaknesses, choose one after considering the specific concept you want to study • Interviews, surveys, field research, content analysis, official records • The best studies utilize more than one research method

  29. 29 Operationalization • Create concrete ways of actually measuring your concept • Fear and violent crime: • Questionnaire item: “How safe do you feel in your house, downtown at night, etc.?” • Official records of violent crime incidents in that neighborhood, downtown, etc.

  30. 30 Population and Sampling • Exactly who or what will you study? • Population – group (e.g., of people) about whom we want to be able to draw conclusions • Since it is generally unfeasible to study ALL members of that population, how will you take a representative sample? • Fear and violent crime: will you include elderly? Teenagers and kids? A particular race or gender?

  31. 31 Observations • Collect the empirical data • Yes, that’s it, make the observations that you will process, analyze, interpret, apply, and review

  32. 32 Data Processing • You have amassed a volume of observations in a form that usually is not easily interpretable • How will you make sense of the observations? • Code the data somehow

  33. 33 Analysis • Manipulate the data (usually with a software program like SPSS) • Goal is to draw conclusions that reflect on the interests, ideas, and theories which initiated our research project • Calculate percentages of those who have been victimized by violent crime, those who fear violent crime, differences among population subsets, etc.

  34. 34 Application • Utilize the research you’ve conducted and the conclusions you’ve reached • Make your findings known to others • Develop policy to address your findings • Determine what mistakes were made that could be corrected in the future • Determine how your research might feed into future research

  35. 35 Linking Measurement and Association • Traditional Deductive Model • Theory Construction • Derivation of Theoretical Hypotheses • Operationalization of Concepts • Collection of Empirical Data • Empirical Testing of Hypotheses

  36. 36 Theory Construction • The scientist creates an abstract deductive theory to describe an aspect of the world • This is largely a logical exercise – the theory must make sense and include concepts relevant to the aspect being studied • Importation theory – individuals import traits and characteristics from one setting which manifest themselves in a new setting

  37. 37 Derivation of Theoretical Hypotheses • Based on this theory, the scientist derives hypotheses relating to the inherent concepts • Prison misconduct stems from the importation of a preexisting belligerent and antagonistic mentality into the correctional institution

  38. 38 Operationalization of Concepts • The scientist specifies precise and specific indicators to represent theoretical concepts – converting the theoretical hypothesis into an empirical one • Misconducts – number of major and minor rule violations while in prison • Importation – measure of gang involvement, race, socioeconomic status as a reflection of strain

  39. 39 Collection of Empirical Data • The scientist collects data relating to the operationalized concepts • Survey 500 prison inmates and the correctional officials in that institution • Discover race, prior gang involvement, prior socioeconomic status, number of rule violations while incarcerated

  40. 40 Analysis • Theoretical concepts seldom permit unambiguous operationalization • All empirical indicators have some defects and can be improved on (the search is endless, though) • Empirical (statistical) associations between variables are imperfect • Specifying the extent that represents acceptance and that which represents rejection is arbitrary

  41. 41 Application • “No statistically significant relationship was found between race, socioeconomic status, and number of misconducts while in prison.” • Communicate the findings to others • Implement the findings if possible • Consider what further research must be done

  42. 42 The Research Proposal • Data Collection Methods • Analysis • References • Schedule • Budget • Problem • Literature Review • Research Questions • Subjects for Study • Measurement

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