Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Methodological considerations for estimating policy effects in the
  context of co-occurring policies   Objective. Understanding how best to estimate state-level policy effects is
important, and several unanswered questions remain, particularly about optimal
methods for disentangling the effects of concurrently implemented policies. In
this paper, we examined the impact of co-occurring policies on the performance
of commonly used models in state policy evaluations.
  Data Sources. Outcome of interest (annual state-specific opioid mortality
rate per 100,000) was obtained from 1999-2016 National Vital Statistics System
(NVSS) Multiple Cause of Death mortality files.
  Study Design. We utilized Monte Carlo simulations to assess the effect of
concurrent policy enactment on the evaluation of state-level policies.
Simulation conditions varied effect sizes of the co-occurring policies as well
as the length of time between enactment dates of the co-occurring policies,
among other factors.
  Data Collection. Longitudinal annual state-level data over 18 years from 50
states.
  Principal Findings. Our results demonstrated high relative bias (>85%) will
arise when confounding co-occurring policies are omitted from the analytic
model and the co-occuring policies are enacted in rapid succession. Moreover,
our findings indicated that controlling for all co-occurring policies will
effectively mitigate the threat of confounding bias; however, effect estimates
may be relatively imprecise, with larger variance estimates when co-occurring
policies were enacted in near succession of each other. We also found that the
required length of time between co-occurring policies necessary to obtain
robust policy estimates varied across model specifications, being generally
shorter for autoregressive (AR) models compared to difference-in-differences
(DID) models.

32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat