1. Testing the Effectiveness of Geo- Behavioural Profiling Systems Professor David Canter & Laura Hammond Director, Centre for Investigative Psychology The University of Liverpool,UK www.i-psy.com

2. Study of effectiveness of various prioritisation strategies 92 offence series in a London borough. All identified series over four years/

3. Various Models Illustrated from the crimes of Jack the Ripper

4. The ‘canonical’ map Nichols 31.8 –3.40 Chapman 8.9 – 6.00 Stride 30.9 – 1.00 Eddowes 30.9 – 1.45 Kelly 9.11- 7.00?

5. The ‘canonical’ map

6. Circle Hypothesis Calculation to Locate Ripper’s Base

7. Central Circle in Whitechapel

8. Centre of Gravity of Murder Locations

9. Two further concepts Criminal Range Decay Functions

10. Criminal ‘range’

11. 0-0.1 0.11-0.5 0.51-0.99 1.00-1.5 1.51-2.00 2.01-2.5 2.51-3 3.01-4 4.01-5 5.01-6 6.01-7 7.01-8 10+ 0 5 10 15 20 25 30 35 Range of Distances traveled by Arsonists The Distance Decay Function, An example from serial arsonists

12. Optimal Function of Distance from Offence to ‘Home’

13. Offence Map: Developing the Search Tool that incorporates various distance functions. 1st Crime 2nd 3rd 4th 5th

14. The system assigns a priority to each known offender using various criteria. Offender IDAddressProbability MO Match 124Location A0.285743118640 427Location B0.270382338980 427Location C0.260351694920 226Location D0.255778610170 48Location E0.232829915250 124Location F0.224459847460.3 124Location G0.219326627120 Prioritised search area

15. 50% of actual offenders are in the top 5 prioritized just by geographical location. iOPS allows this to be improved by also using M.O. matching. Criteria Distance from centre of circle defined by 2 furthest crimes Distance from centre of gravity (centroid) Optimum negative log decay function Negative log decay function with buffer

16. (N = 92) ModelMean Rank (S.D)Median Rank Exponential Function - High B-value 8.86 (8.446)4 Logarithmic Function -Low B-value 9.04 (8.402)4.5 Logarithmic Function -High B-value 8.92 (8.350)5 Centre of Gravity 9.21 (8.256)5 Logarithmic Function -Optimal B-value 8.95 (8.349)5 Logarithmic Function with Buffer Zone- Optimal B-value 9.73 (8.674)5.5 Exponential Function - Low B-value 10.18 (8.411)7 Exponential Function - Optimal B-value 10.55 (8.461)7 Exponential Function with Buffer Zone- Optimal B-value 10.61 (8.888)7 Last Offence 11.11 (8.416)9 First Offence 11.96 (8.424)10..5 Centre of Minimum Distance 12.52 (8.066)14 Centre of Circle 15.15 (7.536)21 Straight Linear Function 21.00 (.000)21 COMPARISON OF 15 DIFFERENT MODELS

17. Need for more context specific examination of crime patterns Taking account of Land use Opportunities for crime Guardianship Targeting Transport routes Temporal sequences

18. Offender 1: 34 CRIMES 1 HOME LOCATION Offender 34 crimes 1 home location

19. Offender 2: 34 CRIMES 1 HOME LOCATION Offender 34 crimes 1 home location

20. 2 Offenders with different distributions of crimse in relation to Southside Centre in Wandsworth Southside Centre Offender 34 crimes 1 home location Offender 34 crimes 1 home location

22. EXAMPLES FROM BURLGARIES IN WANDSWORTH PNC data 12 offenders All crime types 1992-present Offender 1: 10 CRIMES 2 HOME LOCATIONS

23. Offender 8: 24 CRIMES 1 HOME LOCATION

24. Offender 3: 20 CRIMES 3 HOME LOCATIONS

25. Offender 2: 21 CRIMES 3 HOME LOCATIONS

26. Offender 7: 13 CRIMES 2 HOME LOCATIONS

27. Offender 5: 19 CRIMES 3 HOME LOCATIONS

28. Offender 11: 48 CRIMES 3 HOME LOCATIONS

29. Offender 12: 53 CRIMES 2 HOME LOCATIONS