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We develop a new Bayesian split population survival model for the analysis of survival data with misclassified event failures. Within political science survival data, right-censored survival cases are often erroneously misclassified as failure cases due to measurement error. Treating these cases as failure events within survival analyses will underestimate the duration of some events. This will bias coefficient estimates, especially in situations where such misclassification is associated with covariates of interest. Our split population survival estimator addresses this challenge by using a system of two equations to explicitly model the misclassification of failure events alongside a parametric survival process of interest. After deriving this model,we use Bayesian estimation via slice sampling to evaluate its performance with simulated data, and in several political science applications. We find that our proposed “misclassified failure” survival model allows researchers to accurately account for misclassified failure events within the contexts of civil war duration and democratic survival.
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Causal Evidence for Theories of Contagious Civil Unrest
Abstract Many types of civil unrest, including protest, violent conflict, and rebellion, have been found to be subject to both inter- and intra-state contagion. These spillover effects are conventionally tested through the application of parametric structural models that are estimated using observational data. Drawing on research in methods for network analysis, we note important challenges in conducting causal inference on contagion effects in observational data. We review a recently developed non-parametric test—the “split-halves test”—that is robust to confounding and apply the test to replication data from several recent studies in which researchers tested for contagion in civil unrest. We find that about half the time findings in the published literature fail to replicate with the split-halves test. Across ten total replications, we do not see strong patterns in terms of which results do and do not replicate. We do, however, find evidence for general contagion in six of the replications, indicating that contagion is a prevalent phenomenon in civil unrest. As such, we recommend that researchers (1) use the split-halves test as a general-purpose robustness check for parametric models of contagion in the study of civil unrest, and (2) consider modeling contagion in research on civil unrest.
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- Award ID(s):
- 2318460
- PAR ID:
- 10548339
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- International Studies Quarterly
- Volume:
- 68
- Issue:
- 4
- ISSN:
- 0020-8833
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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