Skip to main content

All Questions

Filter by
Sorted by
Tagged with
3 votes
2 answers
71 views

Limitations of propensity score matching

While studying propensity score matching, I was struck by the following thought: When we are running a logistic regression model to estimate $p(Z=1∣X)$ through some form of parametrization and we are ...
richardjoseph's user avatar
0 votes
1 answer
36 views

Modeling approaches for conditional probability distribution, applied to Propensity Score estimation for IPW (causal inference)

I'm trying to understand and ideally implement the Inverse Probability Weighting approach to estimate a causal effect. My ressources so far have been Pearl's Primer and the book "What If?". ...
ThighCrush's user avatar
4 votes
1 answer
255 views

In a doubly robust learner, do the covariates need to be the same for the outcome model and the propensity model?

In a doubly robust learner/estimator, do we need to use the same feature set X when creating the outcome model and the propensity model? Or could we use a subset of X for the propensity model or even ...
user427024's user avatar
3 votes
1 answer
120 views

What is the math rationale behind the inverse probability weighting?

Papers say IPTW (inverse probability weighting) is superior to PSM (propensity score matching) because it does not necessarily drop observations, whereas PSM drops those observation not paired. IPTW ...
Tom Hsiung's user avatar
2 votes
1 answer
41 views

Propensity score weighting with post-treatment variables

It's been emphasized to balance pre-treatment variables when doing propensity score weighting (PSW) as balancing post-treatment variables can introduce bias. I want to ask your insights on the case ...
HYL's user avatar
  • 377
1 vote
1 answer
272 views

In propensity score matching, is the estimand to be estimated the ATE or the ATT?

In the propensity score matching literature (Central Role of the Propensity Score by Rubin), the treatment effect estimand is referred to as the "Average Treatment Effect" (ATE). However, in ...
user321627's user avatar
  • 4,260
0 votes
0 answers
49 views

Does G-computation have any advantages over propensity score based methods for very small sample sizes (e.g., <40)

I am looking into the use of g-computation methods as an alternative for causal inference analysis to propensity score based methods (e.g., IPTW, matching). Does anyone have any examples of using this ...
brookskieran's user avatar
0 votes
1 answer
39 views

If I use entire data, the IPW is effective?

When it comes to causal inference, if I use the entire population data, is Inverse Probability Weighting (IPW) still effective? I have access to the entire population data and need to conduct some ...
user1190107's user avatar
1 vote
0 answers
108 views

Assessing whether the probability of being assigned treatment is equal (or reasonably close) between two individuals/groups [closed]

I'm currently studying the textbook Design of Observational Studies, second edition, by Rosenbaum. Chapter 3 Two Simple Models for Observational Studies says the following: 3.1 The Population Before ...
The Pointer's user avatar
  • 2,204
3 votes
1 answer
165 views

What are the main pros and cons of the most commonly used weighting methods?

There are many methods to generate balancing weights in observational studies (see, for example, the many methods implemented in the amazing WeighIt package). I have seen some great discussions about ...
Charly Marie's user avatar
0 votes
0 answers
60 views

Propensity Score Matching and Weighted Regression Analysis

I have a dataset of ~N=1000 and I want to estimate the average causal/treatment effect of an exposure on an outcome. I've used propensity score matching to balance baseline covariates, and my matched ...
J2019's user avatar
  • 1
1 vote
0 answers
37 views

How to use propensity scores in real examples

I am trying to understand how to use propensity score matching in a real world example (e.g. case control study). Step 1: Based on what I understand, I think a Logistic Regression is first used to ...
user avatar
0 votes
1 answer
78 views

Causal inference and Propensity score

I am trying to understand Rubin's causal model but I can not make the connection between certain notions. The problem of causal inference lies in calculating the counterfactual, i.e. knowing what the ...
Guillaume's user avatar
5 votes
1 answer
417 views

How to derive the GMM estimator for the Covariate Balancing Propensity Score?

The covariate balancing propensity score (CBPS) described by Imai and Ratkovic (2014) involves fitting a logistic regression for the propensity score $\pi_\beta(\mathbf{X}) = P(T = 1\vert\mathbf{X})$ ...
Noah's user avatar
  • 36.8k
1 vote
0 answers
20 views

Is a MSM with no lagged values equivalent to simply using IPW to balance a data set?

I am working on a project employing a panel data set with a large N but a fairly small T (5 time periods). MSMs seem like a good strategy, but I am wary of the incorporation of lagged values since ...
Brian Lookabaugh's user avatar
2 votes
0 answers
56 views

IPW Weights for Marginal Structural Models for Different Estimands

As Blackwell and Glynn 2018 note, an interesting property of marginal structural models is their ability to estimate treatment effects that account for the dynamic properties of panel data. For ...
Brian Lookabaugh's user avatar
2 votes
1 answer
111 views

How to obtain the (weighted or unweighted) L1 imbalance measure for "raw" data

I have two questions regarding the JASA paper, Multivariate Matching Methods That Are Monotonic Imbalance Bounding, by Iacus et al. (2011), the authors produce Figure 2 (left panel) where they compare ...
yungmist's user avatar
1 vote
0 answers
38 views

How to estimate interpretable treatment effects using a marginal structural model?

Say that I estimate a marginal structural model with weights obtained by inverse probability weighting. Imagine that my model looks something like: $Y_t = X_t + X_{t-1}$ again, with observations ...
Brian Lookabaugh's user avatar
1 vote
0 answers
126 views

Variance of Influence Functions, Cross-fitting, and the Propensity Score

Following example 2 in this paper, suppose I wanted to estimate $\psi = E[E[Y|X,A=a]] $ and I had an influence function follows: $$ IF(\psi) = \frac{A}{\pi(X)}\{Y-\mu(X)\} - \psi $$ where $\pi(X)$ is ...
Roy Z's user avatar
  • 43
2 votes
1 answer
77 views

Treatment Effect Insignificant with OLS but Significant After IPTW

I'm working with some observational data and wanted to assess the effect of variable (D) on outcome (Y) after controlling for a vector of covariates (X). As the data is observational, I wanted account ...
statslearner12's user avatar
1 vote
0 answers
26 views

Is there relationship between propensity score based causal inference and sampling weights?

Consider observational study with single outcome $Y$, single covariate $X$ and treatment assignment variable $W$. Under unconfounded treatment assignment assumption, $E_{sp}[Y(1)]=E[\frac{Y_i^{obs}W_i}...
user45765's user avatar
  • 1,465
1 vote
0 answers
303 views

Do the weights of IPTW have to sum up to the population size?

I'm new to Inverse Probability of Treatment Weighting and trying to understand the mechanism. From several practical guides I understood, that the weights should add up to the population size for ...
TiTo's user avatar
  • 281
3 votes
0 answers
343 views

Estimation of Propensity Score using Random Forests

Suppose that one has a binary treatment $Z$, and assume that $Z=1|X=x \sim Bern\left(e(x)\right)$. Furthermore, suppose I want to estimate the propensity score by a random forest. Are there ...
mich95's user avatar
  • 111
2 votes
0 answers
63 views

can someone explain the application of row.weights and sampling.weights in lavaan? [closed]

I am trying to include the weight derived from Inverse Probability of Treatment Weighting (IPTW) into a structural equation model (SEM). However, it is unclear how it should be incorporated into the ...
stat_ocean's user avatar
1 vote
1 answer
482 views

Difference between normalized difference and standardized mean difference in cobalt?

In Imbens & Wooldridge (2009, p. 19), they define the normalized difference as: whereas the cobalt's package standardized mean difference uses by default (for the ATE) "the 'pooled' standard ...
SEL's user avatar
  • 187
1 vote
1 answer
168 views

Propensity Score Matching at the district level and selecting variables

I am trying to use PSM for program evaluation. My data is at the individual level and I would like to do the PSM at the district level (match districts with each other rather than individuals). Based ...
mridhula's user avatar
0 votes
1 answer
759 views

Formula for standardized mean difference in Cobalt package for categorical variables

I am having troubles in understanding the formula in cobalt package used for standardized mean difference calculation in BINARY variables ...
user19745561's user avatar
0 votes
0 answers
31 views

Confounding variables are nested with treatment, not able to be measured, how to address the influence from confounding factors?

We gathered driving data from two cohorts of drivers belonging to the same age group. The first cohort, Group A, utilized System A (treatment group), whereas Group B drove vehicles without this system ...
AsleepOrDead's user avatar
1 vote
1 answer
79 views

How can you rewrite the estimand in terms of propensity scores? Dowhy question

I am going through the backdoor criterion and how we get from an expression involving do to one which doesn't as below. What i don't quite get is how to rewrite this estimand in terms of propensity ...
Maths12's user avatar
  • 579
1 vote
1 answer
67 views

Invalid use of Propensity Score Matching?

I wonder if using a propensity score in the following situation is wrong. Imagine I have the next causal model $$X = N_x$$ $$Y = f(X, N_y)$$ $$ Z = g(X, Y, N_z)$$ Where $N_z, N_y, N_x$ are ...
Nicolas Beltran's user avatar
1 vote
1 answer
236 views

How to Evaluate and Visualize the Positivity Assumption for the ATT

I am trying to formally evaluate and visualize the satisfaction of the positivity assumption when estimating the ATT using R and I am having a tricky time figuring out how to do so. As Greifer and ...
Brian Lookabaugh's user avatar
2 votes
1 answer
321 views

How do matching/weighting outperform regression adjustment for making causal inferences? [duplicate]

In reviewing my notes about making causal inferences under the selection on the observables identification strategy, I reviewed some pieces that make critiques against contemporary strategies in ...
Brian Lookabaugh's user avatar
1 vote
1 answer
166 views

Whether covariates that are balanced at baseline should be put into propensity score matching

I am performing a logistic regression under propensity score matching. Before matching, the baseline characteristics of intervention group A and intervention group B are statistically described, where ...
tumidou's user avatar
  • 75
2 votes
0 answers
116 views

Using propensity score methods with multilevel time series data

I wanted to understand whether it would be feasible to use propensity score matching/weighting/stratification on my data. I'm investigating a region of the world where a number of countries joined an ...
David's user avatar
  • 21
3 votes
1 answer
53 views

Does Propensity Score theorem invalidate linear regression?

The propensity score theorem in Causal Inference implies that $E[T|X]=E[T|p(X)]$, i.e. it is sufficient to control for the propensity score to retrieve the average causal effect. Then, we can use a ...
Oragonof's user avatar
2 votes
0 answers
148 views

Propensity score non parametric estimation

In several papers, in the 'double machine learning' literature, the propensity score (a nuisance parameter) is estimated non parametrically. It is a bit unclear how this estimation is performed, as ...
mich95's user avatar
  • 111
2 votes
0 answers
27 views

What to make of differeing results from standardized means and density when balancing a data set?

I am attempting to estimate the effect of a treatment (pko) on a specific outcome and I am using IPW to do so, along with nearest neighbor matching and coarsened ...
Brian Lookabaugh's user avatar
7 votes
1 answer
265 views

Are only confounders used to generate propensity scores for propensity score matching/IPW?

If the purpose of a propensity score is to generate a "propensity" of a unit receiving treatment, then is it correct to say that the predictors of the treatment need not be confounders (...
Brian Lookabaugh's user avatar
3 votes
0 answers
242 views

IPW Weights Are "1" For Treated Units

I am in the process of setting up my analysis using IPW with the R package WeightIt. My issue is that my weights seem off from the examples and reading materials I ...
Brian Lookabaugh's user avatar
1 vote
0 answers
35 views

Experiment Design with Known, Targeted Probability of Receiving Treatment

Is there a name in the literature for the following experimental design? Suppose we have $i=1,...,n$ individuals in our sample. Denote their baseline covariates, binary treatment assignment indicator, ...
gbrlrz017's user avatar
  • 185
2 votes
1 answer
233 views

Merits of different matching & weighting methods for multiple treatments

I have three land use classes (natural farming, chemical farming, and forest) and would like to compare the densities of different bird species between them. I would like to get the ATE (I think). I ...
user372167's user avatar
1 vote
1 answer
129 views

Selecting optimal iteration for GBM purposed to obtain propensity score estimation

I am interested in propensity score estimation by GBM. I am reading Propensity Score Analysis by Bai and Pan. The book suggested several metric to evaluate balancing of propensity score by GBM. In GBM ...
user45765's user avatar
  • 1,465
1 vote
1 answer
124 views

Positivity, Causal Inference and Machine Learning methods

I ran into a problem where the predicted probabilities of being treatment/control from a machine learning model (the XGB model) matches the actual outcome almost exactly and have area under the curve (...
Stat Novice's user avatar
2 votes
0 answers
149 views

Marginal structural model - help with some concepts

I'm trying to gain some (deeper) understanding of MSM's - what exactly they are and when they might be appropriate to use. Are my thoughts on the following correct (please feel free to correct any ...
LucaS's user avatar
  • 857
1 vote
0 answers
205 views

Power calculation for observational study vs using propensity score matching estimating treatment effect

For case-control study study, one can calculate sample size to determine power of the study with respect to particular estimator of interest. Suppose I am interested in treatment effect in case ...
user45765's user avatar
  • 1,465
1 vote
0 answers
49 views

Why does normalizing difference score>0.25 indicates selection bias which cannot be corrected by regression?

I am reading Propensity Score Analysis(2014) by Guo and Fraser chapter 1 section 4. Denote $\Delta_X$ normalizing difference score of covariate $X$. "Following Imbens and Wooldridge, a $\Delta_X$ ...
user45765's user avatar
  • 1,465
3 votes
1 answer
421 views

Entropy balancing---how do we assess overlap?

I am familiar with propensity score weighting. I set up the propensity score model, and then generally check for balance and overlap in propensity score to ensure that assumptions are met. However, I'...
random_walk's user avatar
0 votes
0 answers
45 views

Is propensity score matching out of favor? [duplicate]

I came across this post, which was largely nonsensical, but a respondent suggested the original poster follow up with two articles: Ho, D. E., Imai, K., King, G., & Stuart, E. A. (2007). Matching ...
tchoup's user avatar
  • 399
1 vote
0 answers
320 views

Regression discontinuity vs propensity score matching

I have recently read some pieces suggesting that regression discontinuity designs could be the best statistical approach for causal inference stemming from non-randomized studies (eg 1 and 2). However,...
Giuseppe Biondi-Zoccai's user avatar
4 votes
1 answer
563 views

What is the positivity assumption required for matching and ATT estimand?

Does ATT estimand require a less stringent positivity assumption in matching? For example, if a small treated group is matched to a large control group, most of the control subjects will be discarded ...
hehe's user avatar
  • 773