Victimization and Factors Influencing

Crime Reporting Lizzy Atkins, Dannia Guzman, Lerato Maphanyane, Marie Jacques Seignon

Objective

❖What factors influence whether individuals report crimes?

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

Setbacks

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

Techniques Used

❖ For loops to classify variables into numeric vs. categorical

❖Random forests❖Decision trees❖Cross validation

Results: Classification Tree

type of crime

activity at time of incident

item taken

property value

damage

type of crime

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

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)

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)

Case Study

type of crime

activity at time of incident

item taken

property value

damage

type of crime

Limitations

❖ Variability of data and getting complete set❖Other potential predictive factors

➢ Previous criminal record➢ Immigration status➢ Geographic location