# npqcs.Q: Function to plot the Q chart In qcr: Quality Control Review

## Description

This function is used to compute statistics required by the Q chart.

## Usage

 ``` 1 2 3 4 5 6 7 8 9 10``` ```npqcs.Q(x, ...) ## Default S3 method: npqcs.Q(x, G, data.name = NULL, limits = NULL, method = c("Tukey", "Liu", "Mahalanobis", "RP", "LD"), alpha = 0.01, plot = FALSE, ...) ## S3 method for class 'npqcd' npqcs.Q(x, data.name, limits = NULL, method = c("Tukey", "Liu", "Mahalanobis", "RP", "LD"), alpha = 0.01, plot = FALSE, ...) ```

## Arguments

 `x` An object npqcd (Non parametric Quality Control Data) `...` arguments passed to or from methods. `G` The x as a matrix, data frame or list. If it is a matrix or data frame, then each row is viewed as one multivariate observation. `data.name` a string that specifies the title displayed on the plots. If not provided it is taken from the name of the object x. `limits` a two-value vector specifying the control limits lower and central. `method` Character string which determines the depth function used. method can be "Tukey" (the default), "Liu", "Mahalanobis", "RP" Random Project or "LD" Likelihood depth. `alpha` it is the the significance level (0.01 for default) `plot` a logical value indicating it should be plotted.

## References

Regina Liu (1995)

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27``` ```## Not run: ## ## Continuous data ## library(qcr) set.seed(12345) mu<-c(0,0) Sigma<- matrix(c(1,0,0,1),nrow = 2,ncol = 2) u <- c(2,2) S <- matrix(c(4,0,0,4),nrow = 2,ncol = 2) G <- rmvnorm(540, mean = mu, sigma = Sigma) x<- rmvnorm(40,mean=u,sigma = S) x <- rbind(G[501:540,],x) n <- 4 # samples m <- 20 # measurements k <- 2 # number of variables x.a <- array(,dim=c(n,k,m)) for (i in 1:m){ x.a[,,i] <- x[(1+(i-1)*n):(i*n),] } M <- G[1:500,] data.npqcd <- npqcd(x.a,M) str(data.npqcd) res.npqcs <- npqcs.Q(data.npqcd,method = "Liu", alpha=0.025) str(res.npqcs) summary(res.npqcs) plot(res.npqcs,title =" Q Control Chart") ## End(Not run) ```

qcr documentation built on May 29, 2017, 3:01 p.m.