Science in General

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Science in General
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Science in General

• Definition a systematically organized body of
  knowledge
• Assumptions
• 1. there is order in nature
• 2. every event has an explanation
• 3. we will never know everything
• Definitions of important terms
• Variable any trait or characteristic which can
  take on a range of values

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Science (continued)

• Hypothesis Question or statement about the
  relationship between two or more variables i.e.,
  is there a relationship between number of police
  on the streets and the crime rate?
• Independent variable (IV) a variable thought to
  have an effect
• Dependent variable (DV) affected variable

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Science (continued)

• Theory an explanation that systematically
  organizes observations and hypotheses
• Basic vs. Applied Research
• Basic--why questions Applied--solve problems
• Cross-sectional vs. Longitudinal Research
• Experimental vs. Ex Post Facto Research

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Some notes about research

• Much research does not pan out
• Some research gets results accidentally
• Research which seems trivial sometimes turns out
  to be important (Golden Fleece award is sometimes
  undeserved)
• We cannot assume that commonsense is correct
• Study of patterns, not individuals

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Errors in observation

• Inaccurate observation (measure record)
• Overgeneralization (sufficient number of
  subjects, replication of studies)
• Selective observation (sufficient number)
• Illogical reasoning, such as gamblers fallacy
  and ex post facto reasoning (logic)
• Ego involvement, Premature closure, Reductionism

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Research methods

• Experiments (manipulation and control)
• Surveys (written and interviews)
• Field or observational research
• Record or archival research (content analysis,
  secondary analysis)
• Case study
• Evaluation research

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Theories

• Importance of theories--they drive research
• Criteria for a good theory
• 1. consistent with known facts
• 2. internally consistent, not contradictory
• 3. parsimonious
• 4. subject to empirical investigation
• 5. able to predict

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Theory building

• Deductive reasoning start with an explanation,
  derive hypotheses and test them. ex family
  instability as a result of social upheaval
• Inductive reasoning gather information and then
  develop a theory. ex Durkheim and crime and
  suicide
• Relationship between research and theory

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Examples of research studies

• Hirschi and social control theory
• Policewomen on patrol
• Kansas City Patrol Experiment
• Group therapy in California prisons

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Relationships vs. Causation

• To be a cause, one variable must be necessary and
  sufficient to affect another variable.
• Something may be necessary but not sufficient
  (intelligence and good grades)
• Could be sufficient but not necessary (isolation
  in early life and mental retardation)

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Three criteria to establish a cause

• 1. Cause must precede effect
• 2. Two variables must be empirically correlated
  (as one changes, the other changes, in a
  systematic fashion)
• 3. Relationship must not be explained away by a
  third variable.
• Storks and babies, polio and pavements
• Large family size and delinquency

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Relationship child abuse Delinquency

• Two methods of study
• Retrospective
• Private residential treatment center, 66 abused
• Runaway shelter, Ohio, 75 abused
• Juvenile delinquents, 40 abused, neglected or
  abandoned

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Relationship (continued)

• Prospective
• 5000 children referred for abuse followed after
  5 years, 14 adjudicated, after 10 years, 32
• A N.Y. study found that 50 of families reported
  had at least one child taken to court as
  delinquent

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Conclusions

• Not cause and effect
• Need for a base rate of comparison--how many
  children are abused, and how many go to juvenile
  court
• There would appear to be a relationship
• Abused children at greater risk, higher p
• Other explanatory variables for the relationship

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Purposes of research

• Exploration--satisfy curiosity, test feasibility
  of a study, develop methods
• Description (Census, polls)
• Explanation
• Units of analysis units observed and described
  to create summary descriptions of all units and
  to explain differences among them

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Units of analysis

• Individuals
• Groups (i.e., families, gangs)
• Organizations (police departments)
• Social artifacts (traffic accidents, court cases,
  prison riots)

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Steps in designing research

• Choosing a research problem
• Reviewing the literature abstracts and
  journals, books, collected readings, computer
  searches (NCJRS), CD ROMS, and the internet
• Conceptualization of variables, hypotheses,
  questions

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Steps in research (continued)

• Selecting how to measure variables
  (operationalization)
• Selecting subjects for the study population and
  sample
• Method making observations and measurements
• Data processing and analysis

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Steps in research continued

• Interpreting the results and their applications

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Research articles

• Who does research?
• Process for getting into print
• Abstract
• Introduction--problem, literature review
• Method--description of subjects, instruments,
  procedure, data analysis used
• Results--descriptive and inferential statistics

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Research article (continued)

• Tables and graphs in results section
• Discussion interpretation of results,
  cautionary notes, directions for future
  research--the next questions

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Research proposal

• Abstract
• Introduction (introduction of the topic,
  literature review, statement of what this study
  would do)
• Method
• Subjects how many? What are their
  characteristics? How will they be selected?
• Instruments what questions will be asked?

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Research proposal (continued)

• Procedure--how will the study be carried out?
• Schedule List each step, and estimate how much
  time each would take (sometimes steps can be done
  simultaneously), and indicate the total length of
  the project
• Budget List all items, the cost of each, and
  the total costs.

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Research proposal (continued)

• Indicate supplies, travel, personnel costs, etc.
  and justify
• Bibliography (based on Introduction--every
  reference in the introduction should have an
  entry in the bibliography, and vice versa
• Appendices

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Layout of research proposal

• Abstract
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• Introduction
• (a few paragraphs)

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Layout (continued)

• Method
• Subjects
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• Instruments
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

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Layout (continued)

• Procedure
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• Schedule
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• (a table is also useful)

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Layout (continued)

• Budget
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
• (again, a table may be used)
• Item Cost

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Layout (continued)

• Bibliography
• author, year of publication, title, journal,
  volume , pages.
• Author, year of publication, title, city of
  publisher, publisher.

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Measurement

• Concepts, hypothetical constructs theoretical
  ideas based on observation but which cannot be
  observed directly
• aggressiveness
• intelligence
• prejudice

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Measurement

• Difficulty of measurement of hypothetical
  constructs
• LaPiere study
• Interchangeability of indicators if several
  different indicators follow the same pattern,
  they are measuring the same concept
• Definition of concept dictionary

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Operational definition

• definition that describes how a concept will be
  measured (intelligence will be measured by the
  scores on the Stanford-Binet and the WAIS-R)
• Considerations for operational definitions
  reliability, validity, norms, precision
• Reliability consistency of measurement.
  Different from accuracy

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Assessing reliability

• Test-retest Scores should not change much over
  a short period of time
• Split-half divide test into two parts, scores
  should be the same on one part as on the other
  for the same individual
• reliability affected by (1) reliability of
  observers and by (2) poor questions

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Validity

• Does the test measure what you want it to
  measure?
• Four types of validity face, criterion or
  predictive, content, construct
• Face validity does it appear to measure what
  you want it to? Do the questions appear relevant?

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Validity (continued)

• Criterion or predictive does the measurement
  predict something we would like to predict?
• Examples ACT and success in college (GPA),
  Screening tests and future job performance
• Determined by applying measure, and then
  determining how well it would have predicted

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Validity (continued)

• Content validity degree to which a measure
  covers the range of meanings in the concept
• Example achievement test, senior test, attitude
  test, personality trait
• Construct based on way a measure relates to
  other variables within a system of theoretical
  relationships (Hirschi)

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Other considerations

• A measure could be reliable but not valid. It
  cannot be valid unless it is reasonably reliable
• Norms measures which provide a basis for
  comparison
• Precision fineness of distinction in measuring.
  How precise? In the social sciences, we are not
  very precise