Working papers

We investigate the role of training in reducing the gender wage gap using the UK-BHPS which contains detailed records of training. Using policy changes over an 18 year period we identify the impact of training and work experience on wages, earnings and employment.

This paper studies inference for the average treatment eect in randomized controlled trials where treatment status is determined according to a \matched pairs" design.

Factor structures or interactive effects are convenient devices to incorporate latent variables in panel data models. We consider fixed effect estimation of nonlinear panel single-index models with factor structures in the unobservables, which include logit, probit, ordered probit and Poisson specications.

In this paper we investigate panel regression models with interactive fixed effects. We propose two new estimation methods that are based on minimizing convex objective functions.

We propose to combine smoothing, simulations and sieve approximations to solve for either the integrated or expected value function in a general class of dynamic discrete choice (DDC) models.

Efron's elegant approach to g-modeling for empirical Bayes problems is contrasted with an implementation of the Kiefer-Wolfowitz nonparametric maximum likelihood estimator for mixture models for several examples. The latter approach has the advantage that it is free of tuning parameters and consequently provides a relatively simple complementary method.

This paper examines the asymptotic behavior of the posterior distribution of a possibly nondifferentiable function g(θ), where θ is a finite-dimensional parameter of either a parametric or semiparametric model. The main assumption is that the distribution of a suitable estimator θ^n, its bootstrap approximation, and the Bayesian posterior for θ all agree asymptotically.

This paper considers inference on fixed effects in a linear regression model estimated from network data.

We find that automatic enrolment substantially increased workplace pension participation among those working for small employers by around 45 percentage points to reach 70% of targeted employees – with most, but not all, brought in at relatively low rates of pension saving.

Many children in developing countries grow up in unstimulating environments, leading to deficiencies in early years’ developmental outcomes, particularly cognition and language. Interventions to improve parenting in the first 3 years of life have a clear impact on these outcomes, but the sustainability of effects is mixed, particularly for scalable interventions. There is little evidence of the effect of following-up an early life intervention with another one immediately afterwards. The objective of this study is to help fill this gap.

I develop a model of a randomized experiment with a binary intervention and a binary outcome. Potential outcomes in the intervention and control groups give rise to four types of participants. Fixing ideas such that the outcome is mortality, some participants would live regardless, others would be saved, others would be killed, and others would die regardless. These potential outcome types are not observable. However, I use the model to develop estimators of the number of participants of each type.

We propose a new specification test for assessing the validity of fuzzy regression discontinuity designs (FRD-validity). We derive a new set of testable implications, characterized by a set of inequality restrictions on the joint distribution of observed outcomes and treatment status at the cut-off.

The LATE monotonicity assumption of Imbens and Angrist (1994) precludes "defiers," individuals whose treatment always runs counter to the instrument, in the terminology of Balke and Pearl (1993) and Angrist et al. (1996). I allow for defiers in a model with a binary instrument and a binary treatment.

Rajasthani women typically leave school early and marry young. We develop a novel discrete choice methodology using hypothetical vignettes to elicit average parental preferences over a daughter’s education and age of marriage, and subjective beliefs about the evolution of her marriage market prospects.

This paper provides inference methods for best linear approximations to functions which are known to lie within a band. It extends the partial identification literature by allowing the upper and lower functions dening the band to carry an index, and to be unknown but parametrically or non-parametrically estimable functions.

This paper is concerned with learning decision makers' (DMs) preferences using data on observed choices from a finite set of risky alternatives with monetary outcomes.

We develop a new methodology to estimate the impact of a financial transaction tax (FTT) on informational efficiency, liquidity and volatility.

In this paper, we exploit a policy designed to randomly allocate roommates in a large South African university to investigate whether inter-racial interaction affects stereotypes, attitudes and performance.

The particular concern of this paper is the construction of a confidence region with pointwise asymptotically correct size for the true value of a parameter of interest based on the generalized Anderson-Rubin (GAR) statistic when the moment variance matrix is singular.