The Center for Statistics and Applications in Forensic Evidence (CSAFE) will offer the Statistical Thinking for Forensic Practitioners Short Course on June 3, 10 and 17 from 10 a.m.–noon CDT.
Statistical Thinking for Forensic Practitioners is a three-part introductory online course covering fundamental concepts from probability and statistics motivated by forensic issues, followed by a detailed investigation of how they are used to assess forensic evidence’s probative value.
Hal Stern, CSAFE co-director and Provost and Executive Vice Chancellor and Chancellor’s Professor of Statistics at the University of California, Irvine, will teach all three sessions.
The short course is free, but registration is required. For more information or to register, visit https://forensicstats.org/courses/#short.
Session 1: Probability Concepts and their Relevance to Forensic Science
Friday, June 3 from 10 a.m.–noon CDT
Probability is the mathematical language of uncertainty. Probabilities are used to describe the frequency or likelihood of events or characterize measurement uncertainty. This session will introduce the laws of probability and their application in forensic settings. Topics will be illustrated with examples drawn from forensic science and relevant legal cases. Specific topics will include:
- Definition and interpretation of probability
- Basic laws of probability
- Conditional probability and independence of events
- Bayes’ Theorem and Bayesian statistics
Session 2: Sampling, Statistics and the Status Quo
Friday, June 10 from 10 a.m.–noon CDT
Statistical ideas such as sampling, point and interval estimation of population quantities and hypothesis testing have direct application in forensic science. This session will start with fundamental ideas about variability and its sources in measurements used in forensic analysis. It will also discuss methods to ameliorate, quantify, model, and interpret variation and uncertainty in evaluating forensic evidence. Session 2 will:
- Talk about variability and its sources, and introduce ideas such as reproducibility, repeatability and accuracy.
- Briefly talk about populations and samples, and describe some sampling methods useful in forensic applications.
- Introduce the idea of estimation of population quantities such as means and proportions and methods to report the uncertainty attached to those estimates.
- Describe how to carry out a test of hypothesis to compare two means and a test of equivalence to compare two means.
- Demonstrate how statistical concepts can be used in the study of current forensic science practice.
Session 3: Quantitative Tools for Forensic Evidence
Friday, June 17 from 10 a.m.–noon CDT
The National Academy of Forensic Science’s report in 2009 and the President’s Council of Advisors on Science and Technology (PCAST) report in 2016 encouraged consideration of quantitative approaches to assessing forensic evidence. This session will review two of the most often-suggested quantitative approaches, the two-stage approach and the likelihood ratio (Bayes factor) approach. Topics will include:
- The two-stage approach to assessing forensic evidence.
- Introduction to the likelihood ratio approach.
- Results of studies comparing different ways of expressing source conclusions.