HMP Peterborough Social Impact Bond - learning exercise

In 2010, the world’s first Social Impact Bond (SIB) was launched at Peterborough Prison. It was used to fund an intervention – ‘The One Service’ – aimed at reducing the reoffending among prisoners discharged after serving a sentence of less than 12 months. Under the terms of the SIB, investors are paid according to how successful the One Service is in reducing reconvictions. If a minimum threshold of a 7.5% reduction in reconviction events is reached across the pilot, payment is triggered. Additionally, there is an option to trigger an early payment if a 10% reduction is noted in the number of reconviction events in individual cohorts. A propensity score matching (PSM) approach was used to estimate impact. For cohort 1, the impact was estimated, by a previous team of independent assessors, to be a reduction in reconviction events of 8.4% (Jolliffe and Hedderman, 2014). Anders and Dorsett (2017a) reviewed the PSM approach, prompted in part by the desire to understand the reasons behind the differences in reconviction rates between prisoners discharged from HMP Peterborough and prisoners discharged from other prisons. They were unable to replicate the results of Jolliffe and Hedderman (2014). This should perhaps be no surprise given the difficulties often encountered with replication attempts. However, the difference between the replication result and the Jolliffe and Hedderman (2014) result was not statistically significant. Following their review, Anders and Dorsett (2017a) recommended that the cohort 1 methodology approach be maintained for cohort 2. They did recommend a change to the sample definition for cohort 2. This was adopted for cohort 2. It is important to note that matching was performed using a dataset that excluded reoffending data. In order to learn more from the evaluation, a separate analysis examined the sensitivity of the estimated impacts to this change in sample definition. This report presents the findings of the sensitivity analysis. The main result is that estimated impacts can vary according to the definition of the sample. However, the differences between the estimates are not statistically significant

New Deal for Young People: Relative effectiveness of the options in reducing male unemployment

The New Deal for Young People was introduced throughout Great Britain in April 1998 as a key element of the government’s welfare-to-work strategy. Participants enter a period of intensive job search known as the ‘Gateway’ and then enter one of four options. In this paper, the relative effectiveness of these options on unemployment exit and job entry is evaluated. The evaluation uses a non-parametric matching approach and finds that the employment option dominates the other NDYP options. Remaining on the Gateway appears more effective than entering the remaining options. The relative strength of these effects changes over time

A Bayesian structural time series analysis of the effect of basic income on crime: Evidence from the Alaska Permanent Fund*

This paper examines the impact of Alaska’s Permanent Fund Dividend on crime. The Dividend has been payable annually to state residents since 1982 and is the world’s longest-running example of a basic income. Initially universal, from 1989 onwards eligibility was withdrawn from an increasing proportion of those in prison. A Bayesian structural time series estimator is used to simulate Alaskan crime rates in the counterfactual no-Dividend case. A comparison with actual rates provides an estimate of the Dividend’s impact. This does not provide strong evidence of an effect. However, incorporating information on Dividend amounts suggests the size of payments is important, with larger amounts reducing crime. There is no evidence that this effect is reinforced by the 1989 change to eligibility. The results demonstrate the potential for a basic income to encourage positive outcomes and lend support to payment being universal rather than conditional

A review of the matching process for the impact analysis of the HMP Peterborough Social Impact Bond

In 2010, the world’s first Social Impact Bond (SIB) was launched at Peterborough Prison. It was used to fund an intervention – ‘The One Service’ – aimed at reducing the reoffending among prisoners discharged after serving a sentence of less than 12 months. Under the terms of the SIB, investors are paid according to how successful the One Service is in reducing reconvictions. If a minimum threshold of a 7.5% reduction in reconviction events is reached across the pilot, payment is triggered. Additionally, there is an option to trigger an early payment if a 10% reduction is noted in the number of reconviction events in individual cohorts. A propensity score matching (PSM) approach was used to estimate the impact. For cohort 1, the impact was estimated, by a previous team of independent assessors, to be a reduction in reconviction events of 8.4% (Jolliffe and Hedderman, 2014). This report reviews the PSM approach, prompted in part by the desire to understand the reasons behind the differences in reconviction rates between prisoners discharged from HMP Peterborough and prisoners discharged from other prisons. Its primary aim is to identify whether there is a need to revise the approach taken before it is applied to cohort 2 (and the final cohort - the weighted mean of cohort 1 and cohort 2). To do this, various amendments to the methodology were explored. It was not possible to replicate the results of Jolliffe and Hedderman (2014). This should perhaps be no surprise given the difficulties often encountered with replication attempts. However, the difference between the replication result and the Jolliffe and Hedderman (2014) result was not statistically significant. Since this review did not identify any clear improvement in the matching process, the conclusion is that the cohort 1 approach be maintained. We also recommend an adjustment to the sample selection in cohort 2. It is important to note that this recommendation is based on the analysis of cohort 1 data and is not informed by cohort 2 reoffending data

Peterborough social impact bond: final report on cohort 2 analysis

In 2010, the world’s first Social Impact Bond (SIB) was launched at Peterborough Prison. It was used to fund an intervention – ‘The One Service’ – aimed at reducing the reoffending among prisoners discharged after serving a sentence of less than 12 months. Under the terms of the SIB, investors are paid according to how successful the One Service is in reducing reconvictions. If a minimum threshold of a 7.5% reduction in reconviction events is reached across the pilot, payment is triggered. Additionally, there is an option to trigger an early payment if a 10% reduction is noted in the number of reconviction events in individual cohorts. A propensity score matching (PSM) approach was used to estimate impact. For cohort 1, the impact was estimated, by a previous team of independent assessors, to be a reduction in reconviction events of 8.4% (Jolliffe and Hedderman, 2014). Anders and Dorsett (2017) reviewed the PSM approach, prompted in part by the desire to understand the reasons behind the differences in reconviction rates between prisoners discharged from HMP Peterborough and prisoners discharged from other prisons. Following their review, Anders and Dorsett (2017) recommended that the cohort 1 approach be maintained for cohort 2. They also recommended an adjustment to the sample selection in Cohort 2. It is important to note that this recommendation was based on the analysis of cohort 1 data and was not informed by cohort 2 reoffending data. Matching was performed for cohort 2 using a dataset that excluded reoffending data. We estimate that the One Service reduced the number of reconviction events among those discharged from HMP Peterborough by 9.7% for cohort 2. The reduction across both cohorts is estimated to be 9.0%, which reached the minimum threshold of 7.5% across all cohorts. This reduction is sufficient to trigger an outcome payment