BiTSLS: Bidirectional Two-Stage Least Squares

A simple R package for estimating bidirectional causal effects using proxy variables.

Installation

# Install from GitHub
# install.packages("devtools")
devtools::install_github("Fhoneysuckle/BiTSLS")

Usage

The Bi_TSLS() function estimates bidirectional causal effects between X and Y:

library(BiTSLS)

# Prepare your data with required variables
data <- data.frame(
  X = ...,  # Treatment variable
  Y = ...,  # Outcome variable
  Z = ...,  # Negative control exposure
  W = ...,  # Negative control outcome
  # Additional covariates (At least one covariate)
)

# Run the estimation
result <- Bi_TSLS(data)

# View results
print(result)  # Effect of X on Y and Y on X

Requirements

Your data must contain: - X: Treatment/exposure variable (numeric) - Y: Outcome variable (numeric) - Z: Negative control exposure (numeric) - W: Negative control outcome (numeric) - Additional covariates are optional (At least one covariate)

Sensitivity Analysis

You can test sensitivity to violations of the proxy structural conditions:

# With sensitivity parameters
result <- Bi_TSLS(data, R_w = 0.1, R_z = -0.1)

License

MIT License