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Full-Text Articles in Statistics and Probability
Estimating Effects On Rare Outcomes: Knowledge Is Power, Laura B. Balzer, Mark J. Van Der Laan
Estimating Effects On Rare Outcomes: Knowledge Is Power, Laura B. Balzer, Mark J. Van Der Laan
Laura B. Balzer
Many of the secondary outcomes in observational studies and randomized trials are rare. Methods for estimating causal effects and associations with rare outcomes, however, are limited, and this represents a missed opportunity for investigation. In this article, we construct a new targeted minimum loss-based estimator (TMLE) for the effect of an exposure or treatment on a rare outcome. We focus on the causal risk difference and statistical models incorporating bounds on the conditional risk of the outcome, given the exposure and covariates. By construction, the proposed estimator constrains the predicted outcomes to respect this model knowledge. Theoretically, this bounding provides …
On The Exact Size Of Multiple Comparison Tests, Chris Lloyd
On The Exact Size Of Multiple Comparison Tests, Chris Lloyd
Chris J. Lloyd
No abstract provided.
Theory And Methods For Gini Coefficients Partitioned By Quantile Range, Chaitra Nagaraja
Theory And Methods For Gini Coefficients Partitioned By Quantile Range, Chaitra Nagaraja
Chaitra H Nagaraja
The Gini coefficient is frequently used to measure inequality in populations. However, it is possible that inequality levels may change over time differently for disparate subgroups which cannot be detected with population-level estimates only. Therefore, it may be informative to examine inequality separately for these segments. The case where the population is split into two segments based on non-overlapping quantile ranges is examined. Asymptotic theory is derived and practical methods to estimate standard errors and construct confidence intervals using resampling methods are developed. An application to per capita income across census tracts using American Community Survey data is considered.
Fixed Bandwidth Theory For Tail Index Estimation, Tucker Mcelroy, Chaitra H. Nagaraja
Fixed Bandwidth Theory For Tail Index Estimation, Tucker Mcelroy, Chaitra H. Nagaraja
Chaitra H Nagaraja
No abstract provided.
On The Size Accuracy Of Combination Tests, Chris Lloyd
On The Size Accuracy Of Combination Tests, Chris Lloyd
Chris J. Lloyd
One element of the analysis of adaptive clinical trials is combining the evidence from several (often two) stages. When the endpoint is binary, standard single stage tests statistics do not control size well. Yet the combined test might not be valid if the single stage tests are not. The purpose of this paper is to numerically and theoretically examine the extent to which combining basic tests statistics mitigates or magnifies the size violation of the final test.