Presentation on theme: "C RIME I N A MERICA : L ET ’ S C LEAN U P T HE S TREETS ! Chris Blees Conner Faught Ryan Shaffer."— Presentation transcript:
C RIME I N A MERICA : L ET ’ S C LEAN U P T HE S TREETS ! Chris Blees Conner Faught Ryan Shaffer
V IOLENT C RIME IN A MERICA Question: What factors lead to violent crime and do those factors vary by the size of the city? –Factors Examined: Percentage of Population Under the Poverty Line People per Family Distance from State Capitol Size of Police Force High School Graduation Rate Annual Precipitation Divorce Rate Average Travel Time to Work Percentage of Population that are Civilian Veterans Median Age
C ITIES U SED IN A NALYSIS 250,000+ Atlanta, GA Aurora, CO Buffalo, NY Phoenix, AZ Pittsburgh, PA Tampa, FA Toledo, OH Santa Ana, CA Oakland, CA Arlington, TX 100,000-250,000 Richmond, VA San Bernardino, CA St. Petersburg, FA Portsmouth, VA Charleston, SC Paterson, NJ Westminster, CO Orange, CA Birmingham, AL Syracuse, NY 60,000-100,000 Upper Darby Township, PA Tustin, CA Tuscaloosa, AL Tracy, CA Temecula, CA Sugar Land, TX Beaverton, OR Bellflower, CA Clifton, NJ Columbia, MO 20,000-60,000 Ames, IA Anderson, IN Binghamton, NY Bloomfield, NJ Bowling Green, KY Bullhead City, AZ Greenburgh Town, NY Hendersonville, TN Kirkland, WA Mansfield, TX
D ESCRIPTIVE S TATISTICS MeanMedianStd DeviationMinimumMaximumCount Under Poverty Line 15.3316.17.6803846063.931 40 People/Family 3.192253.1050.3454650342.84.72 40 Distance from State Capitol 134.599.5125.99104570426 40 Police Officers 421.425166569.313842493220 40 HS Graduation % 65.3665.9516.3330141731.290.1 40 Precipitation 34.2138.815.088096854.755 40 % Divorced 10.267510.72.708712224.215.1 40 Time to Work 24.595245.4482624851541.9 40 % Civilian Veterans 11.4911.553.081441554520.8 40 Median Age 33.06533.23.85543572323.641.8 40
E XPECTED R ESULTS Independent VariableExpected Relationship Percentage of Population Under the Poverty Line Positive People Per FamilyPositive Distance From State CapitolPositive Size of Police ForceNegative High School Graduation RateNegative Annual PrecipitationPositive Divorce RatePositive Average Travel Time to WorkNegative Percentage of Population that are Civilian Veterans Negative Median AgeNegative
R EGRESSION A NALYSIS Regression Statistics Multiple R0.883752474 R Square0.781018435 Adjusted R Square0.70550755 Standard Error244.764056 Observations40 ANOVA dfSSMSFSignificance F Regression106196507.9619650.792510.3433.76919E-07 Residual291737373.8559909.4431 Total397933881.775
R EGRESSION A NALYSIS, CONT. CoefficientsStandard Errort StatP-value Intercept995.13551381269.0848420.7841363170.439318415 % under Poverty Line28.5909644210.179921512.8085643290.008813091 Average Number of People/Family-261.5593937231.4495346-1.1300925450.267697831 Distance From State Capital(Miles)0.6340591330.4273809861.4835922820.14870513 Police Officers (2008)0.1561900910.0854067161.8287799610.077734615 High School Graduates (Percentage)-9.9124983624.127235369-2.4017283910.022949078 Average Precipitation (inches)6.8740696693.8865496081.7686818290.087465669 % population divorced34.6559014221.01482041.6491171830.109916154 mean travel time to work27.8606954812.241405362.2759392950.030416635 % of population that are civilian veterans-44.1099945720.55095204-2.1463723180.040341187 median age-6.94604119314.88362894-0.4666900270.644208808
L INEAR R ESULTS Independent VariableExpected Relationship Percentage of Population Under the Poverty Line Positive People Per FamilyNegative Distance From State CapitolPositive Size of Police ForcePositive High School Graduation RateNegative Annual PrecipitationPositive Divorce RatePositive Average Travel Time to WorkPositive Percentage of Population that are Civilian Veterans Negative Median AgeNegative
V ALIDITY Because the test for homoscedasticity for the predicted values versus the residuals produces a notable ovoid shape, and because the histogram of the residuals produced a curve with a normal, bell-curve shape, the model appears to be valid.
C ONCLUSIONS Of the factors we chose, only four had a significant impact on violent crime rates nationwide. –Percentage of the population under the poverty line. –High school graduation rate. –Mean travel time to work. –Percentage of the population that are civilian veterans. Possible limitations of our model could include: –Small sample size (40 cities). –Data taken from 2000. –Only examines violent crimes.
S OURCES http://www.city-data.com/ 2000 U.S. Census Bureau of Justice Statistics