Statistical Modelling in the Investigation of Stranger Rape

• NCJ Number: 231492
• Journal: Journal of Investigative Psychology and Offender Profiling Volume: 7 Issue: 1 Dated: January 2010 Pages: 31-47
• Author(s): Mirjam Ter Beek; Paul Van Den Eshof; Bas Mali
• Date Published: January 2010
• Length: 17 pages
• Publication Format: Article
• Publication Type: Research (Applied/Empirical)
• Language: English
• Country: United Kingdom

Annotation

The objective of this study was to develop statistical models for the prediction of basic offender characteristics in offenses of stranger rape.

Abstract

A sample of stranger rape offences (n = 271) registered in the Dutch Violence Crime Linkage Analysis System database in the Netherlands between 1997 and 2007 was studied with the objective of developing statistical models, which give an indication of the probability of basic offender characteristics. Observable crime characteristics concerning the modus operandi, interaction between the offender and the victim, violence, precautionary measures, and sexual behaviors were selected in the dataset. Offender characteristics were selected based on their usefulness for the police organization in narrowing the scope of a criminal investigation. Spatial behavior, criminal history, and living situation of the offender were selected. From the predictive models, four out of five achieved a correct rate of over 70 percent, and all models predicted better than the best guess method. The proposed models for distance and prior convictions for violence seem particularly promising. Both these models show an improvement of correctly predicted offender characteristics of more than 20 percentile points compared with that which could have been estimated based on the average in the total sample. The predictive value of the models needs to be tested further with 'new offences', which were not used to construct the model. In general, the current study supports the finding that crime characteristics can be used to get an indication of the probability of certain offender characteristics. Nevertheless, for an understanding of the relationship between the crime characteristics and offender characteristics, a further development of a theoretical framework is urgently necessary. Tables and references (Published Abstract)