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Theory PowerPoint Presentation

Theory

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Theory

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Presentation Transcript

  1. Theory • An explanation that systematically organizes the facts • Five criteria for a good theory • Consistent with the known facts • Logical, internally consistent • Parsimonious • Subject to empirical investigation • Able to predict

  2. Empirical Research Methods • Case study • Survey • Written (group or mailed) • Interviews (face to face or telephone) • Observation • Records • Experiments • Longitudinal

  3. Theory models • Elephant model • Proportion of variance model • St. Louis model

  4. Proportion of Variance Model

  5. St. Louis Model

  6. Measuring crime • How much crime is there? • What are the patterns and trends • Who commits crime? • What is the nature of criminality? • Without such information • Explanations would not be possible • Rational policies would not be devised

  7. Three ways to measure crime • Uniform Crime Reports (UCR) • Victimization surveys (NCS) • Self-report studies • Necessity of having more than one way of measuring crime

  8. Uniform Crime Reports • Compiled by the FBI as received from over 16,000 police departments • Type I offenses (murder, rape, robbery, aggravated assault, burglary, larceny, motor vehicle theft, arson) • Type II offenses: all other offenses other than traffic violations • Characteristics of individuals arrested

  9. UCR (continued) • Crimes cleared by arrest • Crime rates (number per 100,000 people, for comparison purposes) • Per cent change between last year and current year

  10. Problems with the UCR • Many crimes are not reported (“Dark Figure” of crime) • Law enforcement practices, politics and PR • Methodological problems • Does not include federal crimes • Police department reporting varies • Element of subjectivity in deciding how to categorize acts

  11. Problems with NCS • Overreporting due to misinterpretation of events • Underreporting (fear, embarrassment, forgetting) • With self-report, might lie

  12. Crime patterns • More crime reported in warm weather • More murders and robberies in December • Higher rates in urban areas, especially violent crime • Highest rates in the West and the South • Lower in the Northeast, lowest in the Midwest

  13. Crime patterns (continued) • Crime more common among the poor, according to UCR • Self-report indicates less class difference • Serious crime is more prevalent among lower SES, while less serious offenses are more evenly spread among all social classes