SSDforR (version 1.1)

Rchart: SPC R-chart using mean range

Description

The R-Chart is designed to detect changes in variation over time. This is one of two forms of the R-chart and should be used with small samples. This function uses the mean range of samples to track variation.

Usage

Rchart(behavior, groupX, bandX, ABxlab, ABylab, ABmain)

Arguments

behavior

behavior variable

groupX

grouping variables (e.g., day)

bandX

number of standard deviations desired (e.g., 2)

ABxlab

x-axis label in quotation marks (e.g., "weeks")

ABylab

y-axis label in quotation marks (e.g., "amount")

ABmain

main title for graph in quotation marks (e.g., "Problem Range")

References

{Orme, J. & Cox, M.E. (2001). Analyzing single-subject design data using statistical proces control charts. Social Work Research, 25(2), 115-127.

} {Go to www.ssdanalysis.com for more information.}

Examples

admit<-c(85,90,80,84,82,79,75,76,80,84,75,80,79,83,88,78,80,85,83,82,89,84,89,91,87,84,77,86,80,
89,81,86,88,83,86,90,86,85,85,87,80,89,NA,86,87,88,89,79,73,75,74,70,75,81,85,75,73,75,
79,70,72,71,69,70,64,60,59,54,53,55,50,54,51,49,48,50,46,55,51,55,49,50,48,51,33)

day<-c(1,1,1,1,1,1,1,2,2,2,2,2,2,2,3,3,3,3,3,3,3,4,4,4,4,4,4,4,5,
5,5,5,5,5,5,6,6,6,6,6,6,6,NA,7,7,7,7,7,7,7,8,8,8,8,8,8,8,9,
9,9,9,9,9,9,10,10,10,10,10,10,10,11,11,11,11,11,11,11,12,12,12,12,12,12,12)

padmit<-c("A","A","A","A","A","A","A","A","A","A","A","A","A","A","A","A",
"A","A","A","A","A","A","A","A","A","A","A","A","A","A","A","A",
"A","A","A","A","A","A","A","A","A","A",NA,"B","B","B","B","B","B","B","B",
"B","B","B","B","B","B","B","B","B","B","B","B","B","B","B","B",
"B","B","B","B","B","B","B","B","B","B","B","B","B","B","B","B","B","B")
Rchart(admit, day, 2, "week", "amount", "Admits to Hospital")