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Subgroup analyses after propensity score matching

For moderation analysis, you need to ensure you have achieved balance within each subgroup of the moderator. The most straightforward way to do so is to match separately within each level of the ...
Noah's user avatar
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1 vote

Subgroup analyses after propensity score matching

If you do the analysis separately for men and women then you cannot get statistics about the interaction -- no p values or confidence intervals or standard errors. On the other hand, the output may be ...
Peter Flom's user avatar
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5 votes
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In propensity score matching, is the estimand to be estimated the ATE or the ATT?

Which estimand is targeted by matching depends on how the matching is specified. There are specifications that allow you to target the ATE or ATT. The most common form of matching in some fields, k:1 ...
Noah's user avatar
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0 votes

Proving the balancing score property of propensity score

Heuristically you can simply think of this as a goodness of fit issue. Suppose that after accounting for PS there is an imbalance in baseline characteristic X. This means there is a defect in how X ...
Frank Harrell's user avatar
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Propensity score matching with near-perfect differentiation

There are a few things that might be going on here. First is that you don't have overlap in your sample, meaning the control units are so fundamentally different from the treated units that you cannot ...
Noah's user avatar
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1 vote

Propensity score matching with near-perfect differentiation

This indicates that the treated and the control units are a-priori not comparable at all. So, solely based on this data on its own, there is no propensity score analysis that can credibly compare them....
Björn's user avatar
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1 vote
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Propensity matching affects significance of polynomial degrees differently

A matched sample is smaller than an unmatched sample, so the variance of coefficient estimates will be larger after matching, leading to larger p-values. It doesn't matter, though; you should not ...
Noah's user avatar
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0 votes
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What to do with large standardized mean difference in ipw analysis

Balance on the propensity score itself is not essential for unbiased estimation of the treatment effect because of the propensity score tautology. The propensity score is a tool used to achieve ...
Noah's user avatar
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