How to create a Marimekko/Mosaic plot in ggplot2

Question

The Marimekko/Mosaic plot is a nice default plot when both x and y are categorical variables. What is the best way to create these using ggplot?

Answer 1

Thanks all who created this entry which really helped me as ggmosaic wasn't doing what I wanted (and not labelling axes properly). The nice function from Z.Lin throws a warning sort of explained in https://github.com/tidyverse/ggplot2/issues/3142 which seems to say that warning, which is technically untrue in its content, is really warning us that the ggplotocracy, bless and thank them, feel that geom_bar shouldn't really have variable widths. I guess I see the point so I went for the function from Jake Fisher and tweaked it to my own needs. In case it's useful to others, here it is:

makeplot_mosaic2 <- function(data, x, y, statDigits = 1, residDigits = 1, pDigits = 3, ...){
  ### from https://stackoverflow.com/questions/19233365/how-to-create-a-marimekko-mosaic-plot-in-ggplot2,
  ### this from Jake Fisher (I think)
  xvar <- deparse(substitute(x))
  yvar <- deparse(substitute(y))
  mydata <- data[c(xvar, yvar)]
  mytable <- table(mydata)
  
  widths <- c(0, cumsum(apply(mytable, 1, sum)))
  heights <- apply(mytable, 1, function(x){c(0, cumsum(x/sum(x)))})
  
  alldata <- data.frame()
  allnames <- data.frame()
  for(i in 1:nrow(mytable)){
    for(j in 1:ncol(mytable)){
      alldata <- rbind(alldata, c(widths[i], widths[i+1], heights[j, i], heights[j+1, i]))
    }
  }
  colnames(alldata) <- c("xmin", "xmax", "ymin", "ymax")
  
  alldata[[xvar]] <- rep(dimnames(mytable)[[1]],rep(ncol(mytable), nrow(mytable)))
  alldata[[yvar]] <- rep(dimnames(mytable)[[2]],nrow(mytable))
  
  chisq <- chisq.test(mytable)
  df <- chisq$parameter
  pval <- chisq$p.value
  chisqval <- chisq$statistic
  # stdResids <- chisq$stdres
  alldata$xcent <- (alldata$xmin + alldata$xmax)/2
  alldata$ycent <- (alldata$ymin + alldata$ymax)/2
  alldata$stdres <- round(as.vector(t(chisq$stdres)), residDigits)
  # print(chisq$stdres)
  # print(alldata)
  
  titleTxt1 <- paste0("Mosaic plot of ",
                      yvar,
                      " against ",
                      xvar,
                      ", ")
  titleTxt2 <- paste0("chisq(",
                     df,
                     ") = ",
                     round(chisqval, statDigits),
                     ", p = ",
                     format.pval(pval, digits = pDigits))
  titleTxt <- paste0(titleTxt1, titleTxt2)
  subTitleTxt <- "Cell labels are standardised residuals"
  
  ggplot(data  = alldata, 
         aes(xmin=xmin, xmax=xmax, ymin=ymin, ymax=ymax)) + 
    geom_rect(color="black", aes_string(fill=yvar)) +
    geom_text(aes(x = xcent, y = ycent, label = stdres)) +
    xlab(paste0("Count of '", 
                xvar,
                "', total = ",
                max(alldata$xmax))) + # tweaked by CE
    ylab(paste0("Proportion of '", 
                yvar,
                "' per level of '",
                xvar,
                "'")) +
    ggtitle(titleTxt,
            subtitle = subTitleTxt) +
    theme_bw() +
    theme(plot.title = element_text(hjust = .5),
          plot.subtitle = element_text(hjust = .5))
}

makeplot_mosaic2(mtcars, vs, gear)
makeplot_mosaic2(diamonds, cut, clarity)