To estimate the effect of an exogenous intervention on a treated unit, such as the implementation of a new criminal justice policy in a given state, a control unit is necessary. Comparing the treated unit’s (let’s say the state of California) time series of the outcome of interest (i.e. violent crime) to the population in which the treated unit is nested (i.e. national time-series) post-intervention would not yield interpretable findings, because it is unknown whether the difference in crime rates was caused by the intervention or some other factor. To navigate this obstacle, California’s crime rates would be compared to a weighted combination of other states chosen to optimally match California’s pre-intervention violent crime trends.
New book publication: Design and Analysis of Time Series Experiments
June 8, 2017 by
SimLab Director Dr. Richard McCleary, co-author Dr. David McDowell, and SimLab Graduate Student Brad Bartos published a new book. Design and Analysis of Time Series Experiments presents the elements of statistical time series analysis while also addressing recent developments in research design and causal modeling. A distinguishing feature of the book is its integration of design and analysis of time series experiments. Readers learn not only how-to skills but also the underlying rationales for design features and analytical methods. Building on the earlier time series books by McCleary and McDowall, Design and Analysis of Time Series Experiments includes recent developments in modeling, and considers design issues in greater detail than does any existing work. Read more about the book and purchase here: https://global.oup.com/academic/product/design-and-analysis-of-time-series-experiments-9780190661564?cc=us&lang=en&#
Manuscript Published to SSRN: Generic Discrete-Event Simulation Model of a Prison
June 6, 2017 by
SimLab graduate student Bradley J. Bartos and SimLab Director Dr. Richard McCleary published a new paper to SSRN, “Generic Discrete-Event Simulation Model of a Prison”. The paper describes a generic discrete-event simulation (DES) model of a prison system. The model tracks individual entities through a prison “career,” beginning with admission and ending with release from custody. Career stage transitions are modeled as discrete events that occur in real time. With each career transition (or state-change) the model pauses to update the appropriate subpopulation databases. Entities carry information tags into and through the model. The tags can be used to create arbitrary subpopulations for forecasting or analysis. Download a version of the paper here.
Manuscript under review: Restoration to Competency of Forensic Patients in California with Dementia/Alzheimer’s Disease
June 6, 2017 by
SimLab graduate students Bradley J. Bartos, Matthew Renner, & Carol Newark along with SimLab Director Dr. Richard McCleary and UCI Criminology professor Dr. Nicholas Scurich have a forthcoming publication, “Restoration to Competency of Forensic Patients in California with Dementia/Alzheimer’s Disease”. The study focuses on criminal defendants found incompetent to stand trial (IST) are sent to state hospitals for treatment to be restored to competency. IST patients diagnosed with dementia and related disorders present a particular challenge to clinicians, since they must be restored successfully within a statutorily mandated timeframe (e.g., 3 years in California for defendants charged with a felony offense). This study examined a comprehensive dataset that included all forensic patients served by California’s Department of State Hospitals from September 2003-February 2016. Download the manuscript here.
Discrete-Event Simulation Modeling
July 10, 2016 by
A discrete-event simulation (DES) model is a type of queuing model that is widely used to analyze phenomena in demography, logistics, transportation, and operations research. Entities enter a system, compete with other entities for resources, and after a waiting period, exit the system. DES models assume that entities in the model experience the system in a series of discrete “career” stages, and movement from one stage to the next is based on transition probabilities. System models become quite complicated rather quickly, requiring computer simulation in order to produce useful output.
Prop 36
June 21, 2016 by
An inefficient reliance on incarceration as a means to reduce crime has led to massive incarceration costs and widespread demand for reform. Criminal Justice policymakers fear they will not be re-elected if they support reforms that are perceived to endanger public safety. The current study examines an instance of the diminishing returns paradox, California’s Substance Abuse and Crime Prevention Act. Using synthetic control group methods, this study evaluates whether SACPA threatened public safety or cost more than it saved, as critics predicted. The results suggest UCR Part 1 property crimes increased and aggravated assault decreased following SACPAs enactment.