This paper proposes a test for missing at random (MAR). The MAR assumption is shown to be testable given instrumental variables which are independent of response given potential outcomes. A nonparametric testing procedure based on integrated squared distance is proposed. The statistic\'s...

I derive the polar representation of Fieller's estimation of confidence sets for ratios and construct a polar plot of the test statistics for all angles associated with the ratios. This procedure helps in visualizing and clarifying, but also systematizing, the features of the Fieller solution....

This study focuses on the role of heterogeneity in network peer effects by accounting for network-specific factors and different driving mechanisms of peer behavior. We propose a novel Multivariate Instrumental Variable (MVIV) estimator which is consistent for a large number of networks keeping...

As mixture regression models increasingly receive attention from both theory and practice, the question of selecting the correct number of segments gains urgency. A misspecification can lead to an under- or oversegmentation, thus resulting in flawed management decisions on customer targeting or...

There is considerable uncertainty about how reproductive factors affect child mortality. Joint determinants are difficult to control adequately for, and the studies that have dealt with selection in the most advanced ways have given diverging results. According to very simple models estimated...

I derive the exact small sample properties of the instrumental variables estimator using a trigonometric approach. The distribution for the estimation error is decomposed into a product of three components - each with an intuitive interpretation. This approach helps the discussion on what...

The Pareto distribution has been used to describe firm sizes in many theoretical models for its convenience and empirical validity. We provide estimates of the Pareto parameters across industries and investigate the determinants of the shape of the firm size distribution in Brazil. The Pareto...

The goal of this paper is to test the Husted model and to inspect the long-run sustainability of Brazilian current account in a very specific period of time (1996-2005) by the use of monthly data. We have tested the inter-temporal budget constraints (IBC) condition via unit root test with...

This paper develops a two-step inference procedure to test for a local one-for-one relation of contemporaneous jumps in high-frequency financial data corrupted by market microstructure noise. The first step develops a new bivariate Lee-Mykland jump test for pre-averaged, intra-day returns. If a...

This paper develops high-frequency econometric methods to test for jumps in the spread of bond yields. We derive a coherent inference procedure that detects a jump in the yield spread only if at least one of the two underlying bonds displays a jump. We formalize the test as a sequential...