# plotEmpiricalNulls: Plot empirical null distributions In OHDSI/EvidenceSynthesis: Synthesizing Causal Evidence in a Distributed Research Network

## Description

Plot the empirical null distribution for multiple data sources.

## Usage

 ```1 2 3 4 5 6 7 8 9``` ```plotEmpiricalNulls( logRr, seLogRr, labels, xLabel = "Relative risk", limits = c(0.1, 10), showCis = TRUE, fileName = NULL ) ```

## Arguments

 `logRr` A numeric vector of effect estimates for the negative controls on the log scale. `seLogRr` The standard error of the log of the effect estimates. Hint: often the standard error = (log(lower bound 95 percent confidence interval) - l og(effect estimate))/qnorm(0.025). `labels` A vector containing the labels for the various sources. Should be of equal length as `logRr` and `seLogRr`. `xLabel` The label on the x-axis: the name of the effect estimate. `limits` The limits of the effect size axis. `showCis` Show the 95 percent confidence intervals on the null distribution and distribution parameter estimates? `fileName` Name of the file where the plot should be saved, for example 'plot.png'. See the function `ggplot2::ggsave()` for supported file formats.

## Details

Creates a plot showing the empirical null distributions. Distributions are shown as mean plus minus one standard deviation, as well as a distribution plot.

## Value

A Ggplot object. Use the `ggplot2::ggsave()` function to save to file.

 ``` 1 2 3 4 5 6 7 8 9 10``` ```# Some example data: site1 <- EmpiricalCalibration::simulateControls(n = 50, mean = 0, sd = 0.1, trueLogRr = 0) site1\$label <- "Site 1" site2 <- EmpiricalCalibration::simulateControls(n = 50, mean = 0.1, sd = 0.2, trueLogRr = 0) site2\$label <- "Site 2" site3 <- EmpiricalCalibration::simulateControls(n = 50, mean = 0.15, sd = 0.25, trueLogRr = 0) site3\$label <- "Site 3" sites <- rbind(site1, site2, site3) plotEmpiricalNulls(logRr = sites\$logRr, seLogRr = sites\$seLogRr, labels = sites\$label) ```