1. Victimization and Factors Influencing Crime Reporting Lizzy Atkins, Dannia Guzman, Lerato Maphanyane, Marie Jacques Seignon

2. Objective ❖ What factors influence whether individuals report crimes?

3. Data ❖ National Crime Victimization Survey (NCVS), 2013 from the National Archive of Criminal Justice Data ❖ Person file: 182,699 observations of 240 variables ❖ Household file: 127,949 observations of 280 variables ❖ Incident file: 7,727 observations of 950 variables ❖ Merged file: 7,727 observations of 826 variables

4. Setbacks ❖ Data file format ❖ Variability within levels ❖ Variable selection not scalable ❖ Residues vs. NAs

5. Techniques Used ❖ For loops to classify variables into numeric vs. categorical ❖ Random forests ❖ Decision trees ❖ Cross validation

6. Results: Classification Tree type of crime activity at time of incident item taken property value damage type of crime

7. Types of Violent Crime Reported: ❖ Sexual attack with serious assault ❖ All types of robbery (attempted or completed, resulting major or minor injury) ❖ Aggravated assault (completed and injured & attempted with weapon) ❖ Threatened assault (with weapon) ❖ Simple assault (completed with injury) ❖ Verbal threat: sexual assault Not Reported: ❖ Rape (completed, attempted) ❖ Sexual assault (without injury) ❖ Unwanted assault contact (without force) ❖ Assault (no weapon or injury) ❖ Verbal threat: rape or assault

8. Types of Personal Theft Crime Reported: ❖ Purse snatching (completed) ❖ Personal larceny (completed ; no contact; $250 or greater value) Not Reported: ❖ Purse snatching (attempted) ❖ Pocket picking (completed) ❖ Personal larceny (attempted; no contact; $1-249 value)

9. Types of Household Theft Crime Reported: ❖ Burglary (completed; forcible entry or unlawful entry without force) ❖ Attempted forcible entry ❖ Household larceny (completed, $250 or greater value) ❖ Motor vehicle theft (completed) Not Reported: ❖ Household larceny (completed, $1-250 value) ❖ Household larceny (attempted) ❖ Motor vehicle theft (attempted)

10. Case Study type of crime activity at time of incident item taken property value damage type of crime

11. Limitations ❖ Variability of data and getting complete set ❖ Other potential predictive factors ➢ Previous criminal record ➢ Immigration status ➢ Geographic location