Who doesn’t like a wikipedia entry control chart
If analysis of the control chart indicates that the process is currently under control (i.e., is stable, with variation only coming from sources common to the process), then no corrections or changes to process control parameters are needed or desired I mean gee whiz this sure could relate to something like I don’t know AFL total game scores?
First thing, lets use fitzRoy
library(fitzRoy) library(tidyverse) ## ── Attaching packages ──────────────── tidyverse 1.2.1 ── ## ✔ ggplot2 3.1.0 ✔ purrr 0.3.2 ## ✔ tibble 2.1.1 ✔ dplyr 0.8.0.1 ## ✔ tidyr 0.8.3 ✔ stringr 1.4.0 ## ✔ readr 1.3.1 ✔ forcats 0.4.0 ## ── Conflicts ─────────────────── tidyverse_conflicts() ── ## ✖ dplyr::filter() masks stats::filter() ## ✖ dplyr::lag() masks stats::lag() library(ggQC) fitzRoy::match_results%>% mutate(total=Home.Points+Away.Points)%>% group_by(Season,Round)%>% summarise(meantotal=mean(total))%>% filter(Season>1989 & Round=="R1")%>% ggplot(aes(x=Season,y=meantotal))+geom_point()+geom_line()+stat_QC(method="XmR")+ylab("Mean Round 1 Total for Each Game") +ggtitle("Stop Freaking OUT over ONE ROUND")
So if we were to look at the control chart just for round 1 in each AFLM season since the 90s it would seem as though that even though this round was lower scoring that there isn’t much too see here.
After all we can and should expect natural variation in scores, wouldn’t footy be boring if scores were the same every week.