README.Rmd

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output: github_document
---

<!-- README.md is generated from README.Rmd. Please edit that file -->

```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  fig.path = "man/figures/README-",
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)
```

# fect

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**R** package for implementing counterfactual estimators in panel fixed-effect settings. It is suitable for panel/TSCS analysis with binary treatments under (hypothetically) baseline randomization. It allows a treatment to switch on and off and limited carryover effects. It supports linear factor models---hence, a generalization of [**gsynth**](https://yiqingxu.org/packages/gsynth/index.html)---and the matrix completion method. 

**Repo:** [GitHub](https://github.com/xuyiqing/fect) (1.0.0) 

**Examples:** R code used in the [tutorial](https://yiqingxu.org/packages/fect/articles/tutorial.html) can be downloaded from [here](fect_examples.R).

**Reference:** Licheng Liu, Ye Wang, Yiqing Xu (2021). [A Practical Guide to Counterfactual Estimators for Causal Inference with Time-Series Cross-Sectional Data](https://yiqingxu.org/papers/english/2022_fect/LWX2022.pdf). *American Journal of Political Science*, conditionally accepted.

## Installation

You can install **fect** directly from CRAN by typing the following command in the **R** console: 

```{r eval=FALSE}
install.packages('fect')
```

You can install the development version of **fect** from GitHub by typing the following commands:
```{r eval=FALSE}
devtools::install_github('xuyiqing/fect')
```

**panelview** for panel data visualization is also highly recommended:
```{r eval=FALSE}
devtools::install_github('xuyiqing/panelView')
```

**fect** depends on the following packages, which will be installed automatically when **fect** is being installed. You can also install them manually.
```{r message = FALSE, warning = FALSE}
## for processing C++ code
require(Rcpp) 
## for plotting
require(ggplot2)  
require(GGally) 
require(grid)
require(gridExtra)
## for parallel computing 
require(foreach)
require(future)  
require(doParallel) 
require(abind) 
```

### Notes on installation failures

1. Mac users who have updated to MacOS BigSur or Monterey will likely encounter compilation problems. See [here](http://yiqingxu.org/public/BigSurError.pdf) for a potential solution.
2. Windows users please consider upgrading R to 4.0.0 or higher and installing the [latest Rtools](https://cran.r-project.org/bin/windows/Rtools/) to avoid C++17 complier errors when installing fastplm. 
3. For Rcpp, RcppArmadillo and MacOS "-lgfortran" and "-lquadmath" error, click [here]( http://thecoatlessprofessor.com/programming/rcpp-rcpparmadillo-and-os-x-mavericks-lgfortran-and-lquadmath-error/) for details.
4. Installation failure related to OpenMP on MacOS, click [here](http://thecoatlessprofessor.com/programming/openmp-in-r-on-os-x/) for a solution.
5. To fix these issues, try installing gfortran from [here]( https://gcc.gnu.org/wiki/GFortranBinaries#MacOS clang4 R Binaries from https://github.com/coatless/r-macos-clang).

## Report bugs

Please report bugs to **yiqingxu [at] stanford.edu** with your sample code and data file. Much appreciated!