runchart

A run chart is a simple analytical tool that helps us understand changes in data over time. - NHS Healthcare Improvement Scotland.

A number of R packages exist to automate statistical process control charts. For example:

The runchart package is different from the above because it focusses solely on run charts and provides the ability to automatically rephase baselines. The package exports a single easy to use function runchart().

Examples

By default - shifts and trends are displayed (triggering at 6 and 5 consecutive points respectively) and the baseline is not rephased:

library(runchart)
library(ggplot2)

df <- data.frame(date  = seq.Date(Sys.Date(), by = "day", length.out = 30),
value = c(4,3,3,2,2,3,3,4,4,4,4,3,3,2,2,1,2,1,0,3,3,4,5,6,7,9,8,7,6,6))

runchart(df)

Both shifts and trends can be independantly suppressed. The baseline can be rephased (triggering at 9 consecutive points):

runchart(df, shift = FALSE, trend = FALSE, rephase = TRUE)

Access the fields behind these plots by setting the output parameter to df:

head(runchart(df, output = 'df'))
#>         date base value shift
#> 1 2018-11-03    3     4    NA
#> 2 2018-11-04    3     3    NA
#> 3 2018-11-05    3     3    NA
#> 4 2018-11-06    3     2    NA
#> 5 2018-11-07    3     2    NA
#> 6 2018-11-08    3     3    NA

Installation

devtools::install_github('jsphdms/runchart')