Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [causalimpact]

CausalImpact R package for estimate the effect of an intervention on a time series.

7
votes
1answer
689 views

Using Google Causal Impact package to assess the significance of a planned intervention

I am using the Causal Impact package in R to infer the causal effect of an intervention in some data which are highly correlated and seasonal. Specifically, i got 17 days of hourly data, intervetion ...
3
votes
2answers
514 views

Odd behaviour in CausalImpact (R)

I'm finding some odd behaviour in Google's CausalImpact R package and wondered if anyone has found the same and knows the cause. If you feed the package a certain length time series, the model snaps ...
3
votes
1answer
827 views

Bayesian Structural Time Series in BSTS package: implementing mixed model

I have been using BSTS package for quite a while and I have found it pretty effective with respect to ARIMAX models. I was wondering whether it would be possible to share regression coefficients in ...
3
votes
1answer
134 views

Synthetic control and unobserved confounders

The synthetic control (cohort) method is a very promising approach to causal inference that has been used in a number of interesting studies. It's particularly useful in situations where data are only ...
3
votes
0answers
62 views

How to calculate causal effects with repeated exogenous shocks over a time series

A rather frequent problem in causal inference is that we come across various shocks over time and try to measure their impact. In the case of a single shock we can use bayesian methods to predict how ...
3
votes
0answers
306 views

Pro and cons between Bayesian structural time series (BSTS) vs difference-in-differences?

Google's paper markets BSTS's benefits over DID such that "In contrast to classical difference-in-differences schemes, state-space models make it possible to (i) infer the temporal evolution of ...
3
votes
0answers
354 views

Specifying seasonality component in Causal impact

How do I supply yearly(month/week of the year) + day of the week seasonality in causal impact? I have 1 year of data in the pre period at daily granularity i.e. 365 data points. would, nseasons =52 ...
2
votes
1answer
289 views

Reduce credible intervals in Causal Impact model

I'm hitting an issue with a causal impact model that I'm building. I'm trying to create a counter factual for daily sales at one store (nseasons = 7). I've included sales for 5 other stores nearby. ...
2
votes
1answer
844 views

causal impact - adding multiple control groups

I want to run an analysis using causal impact tool. I have one test group but multiple control groups. Can I use multiple control groups all together in one model? Eg: Y = test and A,B,C as control ...
2
votes
1answer
201 views

How to choose Control groups for Causal Impact algorithm?

I'm running an experiment and want to use the Causal Impact function to assess how well it performs. I have 10 different cities. I'm looking to find out what is the best method for choosing which ...
2
votes
0answers
341 views

Remove price and promotion effects from sales time series

I'm trying to measure the effect of an in-store media campaign on the sales. I have sales data along the time for test (treated) stores and control (not treated) stores. Before comparing test and ...
1
vote
2answers
663 views

How to study the causal impact on multiple time series of interest against multiple baselines

My data consist of time series of Wikipedia hits for football players. I want to use the CausalImpact package to explore the effect of the World Cup on their ...
1
vote
1answer
168 views

How to reason about causal effect in time series when the treatment group reacts even before treatment?

Context: I'm running into a strange phenomenon about treatment effect and causality that I'll try to recreate here. Let's say I'm doing an observational study: Do people spend more time online as a ...
1
vote
1answer
474 views

Difference between using propensity score matching and CausalImpact for causal inference?

I'm investigating causal effect in some financial data, and I'm using two different approaches: propensity score matching with stratification and the CausalImpact package for Bayesian structural time ...
1
vote
1answer
139 views

Evaluating the Impact of National Policies Using Panel Data

I have a panel data set covering various countries over various years. I have information about the years in which these countries published an entrepreneurship policy - some countries only published ...
1
vote
2answers
121 views

CausalImpact: Valid for Single Market [closed]

Is it possible to use the R package CausalImpact (Brodersen et. al, 2015) to estimate the incremental lift of running a local TV ad campaign in Iowa City,IA? We are also running national TV ads across ...
1
vote
1answer
300 views

Scaling control time series with CausalImpact

I'm doing Causal Impact analytics with this python package. Since my control time series have a much larger scale (100-10000 times larger) than my modeled variable, at some point I tried to scale the ...
1
vote
1answer
197 views

Synthetic Control and Causal Analysis

I am creating a synthetic control variable in which I want to use in order to perform a causal impact analysis of our marketing campaign. The goal is to find a set of predictor time series that are ...
1
vote
1answer
276 views

Causality Analysis and test of Independence

First the problem: I am refering to lecture note, on page 480, 2nd paragraph, it mentions If X is in fact useless for predicting Y given Z, then an adaptive bandwidth selection procedure (like ...
1
vote
1answer
333 views

CausalImpact: model in the paper and default in the package

I was utilising CausalImpact for a study. Only recently did I realise that the model described in the associated paper was different to the default model implemented in the package. The paper was ...
1
vote
1answer
710 views

What does Posterior tail-area probability mean in Causal Impact?

I'm new to CausalImpact package in R. I'm trying to understand what the p-value or Posterior tail-area probability mean in the summary. Does it mean that because the p-value is very low, the chance ...
1
vote
1answer
123 views

Estimation of treatment effect when there is an unknown and variable coverage of the population

I am not sure if I am using the correct terminology, something must be written about the following problem, but I cannot find it by searching. I am presently analyzing data about the effect of ...
1
vote
1answer
230 views

Missing Data in CausalImpact and Additional Covariates

I am looking at the fantastic R package CausalImpact and had a couple questions hopefully someone can help with. What should be done when there are 0 values in a ...
1
vote
0answers
55 views

Default CausalImpact Package

I am trying to gain an understanding of the CausalImpact package and the BSTS approach. Consider the following model: $y_t = \mu_t + z_t + \epsilon_t$, where $\epsilon_t \sim N(0,s^2)$, and $\mu_{t+...
1
vote
0answers
30 views

inclusion of static variables as covariates [closed]

Is there a clear way to include static variables e.g. elevation as covariates in the CausalImpact pacakge. Any guidance would be greatly appreciated. Anand
1
vote
0answers
26 views

Assesing impact for rolling enrollment data

I'm running an experiment where some of the users are shown a new widget when they become eligible (some conditions that are unrelated to the experiment itself). I have a control counterfactual group ...
1
vote
1answer
65 views

Is it possible to predict the pre-intervention period rather than the post-period using Google's CausalImpact function?

I want to use to Google's causal impact function to impute the effect of an intervetion. However, my data is structured as: pre-period=1991-1995, intervetion occurs, post-period=1996-2017. To clarify, ...
1
vote
1answer
108 views

Explaining the results of the CausalImpact package where effect is not statistically significant

I've been using the CausalImpact package to compare patent renewal rates across different classes of patents (to determine whether subject matter decisions have particular impacts on the rise or fall ...
1
vote
0answers
155 views

Causal Impact: Continuous Pre-Intervention to Post-Intervention Time Periods?

Within the context of using R package CausalImpact (Brodersen et. al, 2015), is it valid to use time Periods that are noncontinuous for the Pre-Intervention and Post Intervention time periods? For ...
1
vote
0answers
114 views

(CausalImpact) How to incorporate prior trend into counterfactual? [closed]

I'm working with the CausalImpact package for predicting a counterfactual time series. From prior analysis, I know that the true counterfactual series ought to show a downward trend, but the package ...
1
vote
2answers
209 views

Meta-Analysis on Effect Sizes with 95% Bayesian CI from CausalImpact R package

I am using the CausalImpact package in R to calculate the impact of a marketing intervention using Bayesian Structural Time Series. This methodology and package is explained in Broderson et al. 2015 ...
1
vote
0answers
281 views

Bayesian structural time series with few data points (using CausalImpact)

I am experimenting with the CausalImpact package https://google.github.io/CausalImpact/CausalImpact.html (Brodersen et al. 2015) which uses Bayesian structural time-...
1
vote
0answers
146 views

Chow Test and Structural Breaks

I am an economics student and we are tasked to make a mini thesis. I was thinking in getting smoking demand determinants and the effect of sin tax (excise tax on tobacco here in the Philippines and ...
1
vote
1answer
55 views

Comparing store sales based on time period

I am trying to refine the way my company validates tests in retail stores for products that we sell. The prior way was only to look at immediate change in dollar and unit sales without taking into ...
1
vote
0answers
94 views

Counterfactual analysis in the absence of an exogenous intervention

I am interested in exploring the causal effect of poverty on the adoption of a number of climate-resilient agriculture practices in sub-Saharan Africa. In exploring the causal effect of poverty (a ...
1
vote
0answers
73 views

Use of accelerated longitudinal designs with interrupted time series or difference and difference models

I am seeking some resources or specific equation specifications for whether or not it is possible to specify comparative interrupted time series models or difference and difference models with some ...
0
votes
1answer
453 views

Q: R - CausalImpact | order of control time series [closed]

My colleagues and I have been using Google's R-package CausalImpact for a while but recently discovered something that we can't quite explain. Depending on the order of including the different control ...
0
votes
1answer
731 views

Extracting Statistics from CausalImpact Summary

Say I have a CausalImpact Summary like this: ...
0
votes
1answer
81 views

How to use a custom model in CausalImpact where preperiod.start is not right after preperiod.end?

I want to train on a period that isn't immediately preceding the prediction period. You can do this using the default causal model but I'm not sure how with a custom model. Straight from the ...
0
votes
2answers
164 views

Interpreting Mediation Output when ACME is stat. sig but ADE and Total are not

The mediation package in R returns results in which: The Average Causal Mediated Effect (ACME) (the effect of the mediator alone) is positive and statistically significant Average Direct Effect (ADE) ...
0
votes
1answer
303 views

The Causal Impact Package in R could not trace the right number in the test group

I have this sample dataset which is as follow: head(data) ...
0
votes
1answer
274 views

How does CausalImpact Prevent Overfitting

I'm using Google Research's Causal Impact package, and I'd like to understand more fully how the package prevents overfitting and selecting a bad batch of the covariates by chance. Here's the ...
0
votes
1answer
546 views

What does the error “pre.period must span at least 3 time points” in the CausalImpact R package mean?

I've been encountering the error "pre.period must span at least 3 time points" when using the package. Can someone help me understand why the package requires me to have at least 3 time points and ...
0
votes
0answers
16 views

Endogenous subgroups in impact estimation

I am using RCT data to estimate the impact of a program. After doing the straightforward analysis, I decided to estimate the program impact by subgroups (treatment status*subgroup). The subgroups were ...
0
votes
1answer
40 views

Using CausalImpact in R, observed data affected by event that could not affect priors

I am just starting out using the Causal Impact package in R. I am looking at observed data where I know there will be periods of extra traffic due to outside forces. However I cant find any unbiased ...
0
votes
0answers
38 views

Impact of propensity model

I have built a propensity model, which gives out probabilities of a customer paying given a collection intervention using a xgboost model. The model has an AOC-ROC of 81% with an accuracy of 77% ...
0
votes
1answer
72 views

How is the posterior tail-area probability calculated?

I am currently using the CausalImpact package for some research and in this context I need to know and be able to explain, how the posterior tail-area probability is calculated in order to reproduce ...
0
votes
1answer
59 views

Incorporating Fixed Effects with Causal Impact

I have observations on a dependent variable of interest, $Y_{ijt}$, where $t \in [1,2,...T]$ denotes the time, $i$ denotes a particular brand and $j$ a specific product item. At $t=k$, there was an ...
0
votes
1answer
50 views

Pre.intervention and post.intervention should be contiguous in CausalImpact?

I am running a CausalImpact analysis on a time series and my pre.period goes from 01.01.15 to 30.03.15. I want my post period to be from 15.04.15 to 17.04.15. Is it ok if I create a time series that ...
0
votes
0answers
145 views

Generalizing “Causal Impact” synthetic controls, to multiple outcomes

Does anybody know a way to generalize the use of the Causal Impact google R package to multiple outcome time series? Say I ran a time series experiment and was able to set up multiple test outcome ...