Two years I started doing CrossFit and have since gotten kind of into it. After the CrossFit Open last year, I decided to dive a little deeper into the stats available and was able to prove, using public data, that I’m not very good at CrossFit.

Even still, the data set was amazing — over a hundred thousand people participated in a series of workouts, with details like height, age, gender and weight on most of them. With this, I started looking for patterns. Do taller people do better at a specific movement? How much does experience in CrossFit affect ranking? This lead me down a rabbit hole that is the statistics community.

## Getting Started with R

I got my introduction to R when writing the JavaScript/HTML front-end for the Code Schools Try R course. Jay McGavren did an amazing job on the content. I still laugh thinking about finding the mean number of limbs in a group of pirates who had obviously been through some hard times.

Try R is still one of my favorite Code School courses. It’s free and only takes about an hour to go through. It also introduces some of the core concepts of R that come in handy by reading the code below.

## (Re)Learnings Statistics

Like most people, I took some statistics in college, but don’t use too much of it on a daily basis. Lucky for me, Coursera has some amazing stats classes. The one I ended up going through was called Statistics: Making Sense of Data, which hit close to what I was wanting to learn.

One of the nice parts about the format was it was taught similarly to how it would be taught at a university — with the main instructors teaching the statistics side, then with shorter follow-up videos detailing how to do the same thing in R.

## A Boxplot Graph

Armed with new information about how to draw information fromβ¦ other information, I went ahead and started making my first graph — a handy boxplot. All the information is loaded into a Postgres database and put together in the following script.

```
# Setup Postgres connection
library('RPostgreSQL')
drv <- dbDriver("PostgreSQL")
con <- dbConnect(drv, dbname="crossfitopen_development")
# Query the database
rs <- dbSendQuery(con,"select info_time_crossfitting, wod1_score
from athletes where mens=FALSE and info_time_crossfitting
is not null and wod1_score > 5")
# Load in our 70k rows
results <- fetch(rs,n=-1)
# Give names to our columns
colnames(results) = c('Experience', 'Score')
# Create R variables for each column in the database
# Creates:
# Experience vector
# Score vector
attach(results)
# Order our Experience vector
Experience = factor(Experience, c('Less than 6 months', '6-12 months',
'1-2 years', '2-4 years', '4+ years', 'Decline to answer'))
# Create Barplot!
boxplot(Score~Experience, range=0, main='WOD 13.1 By Experience (Women)')
```

Code language: PHP (php)

This pulled up an easy-to-understand Boxplot.

Each vertical box represents what 50% of the population on that vertical achieved, with the line inside the boxplot representing the median for that segment. Seeing as how I’d been CrossFitting for 1-2 years, and only scored 100 on this workout, I was sad to see my score was in the bottom 25% for my group. I knew I had to look deeper to see how I compared.

## Having Fun With XKCD

I stumbled upon the XKCD Package For R not too long after, and decided to have some fun with this data. This library is plain out amazing, and impressive. Looking at the examples on the page alone I knew it was way over my head being still very new to R. But with one chart in mind — my ranking on the 5 workouts — I decided to start writing a graph using the XKCD style.

```
library(extrafont)
loadfonts()
library(xkcd)
# Bring in the data!
# workout=c(1:5) - creates a range from 1-5, so 1,2,3,4,5
# c(16...) - These are my percentiles for the five workouts, resepectively
scores <- data.frame(workout=c(1:5), rank=c(16.71, 4.21, 19.61, 4.9, 19.38))
# Define how much of the X and Y access to show.
# In our case, we'll show all of the Y access,
# but only 1-5 on the X access side.
xrange <- range(scores$workout)
yrange <- range(c(0,100))
ratioxy <- diff(xrange) / diff(yrange)
# Let's create XKCD style stick figure
# I blatantly copied this part from the sample code
mapping <- aes(x, y,
scale,
ratioxy,
angleofspine ,
anglerighthumerus,
anglelefthumerus,
anglerightradius,
angleleftradius,
anglerightleg,
angleleftleg,
angleofneck)
# The c(1.5,4.5) reprents the X coordinates of each of the 2 stick figures --
# likewise for the y coordinate. The rest of these control the arms and legs
dataman <- data.frame( x= c(1.5,4.5), y=c(80, 70),
scale = 17,
ratioxy = ratioxy,
angleofspine = -pi/2 ,
anglerighthumerus = c(-pi/6, -pi/6),
anglelefthumerus = c(-pi/2 - pi/6, -pi/2 - pi/6),
anglerightradius = c(pi/5, -pi/5),
angleleftradius = c(pi/5, -pi/5),
angleleftleg = 3*pi/2 + pi / 12 ,
anglerightleg = 3*pi/2 - pi / 12,
angleofneck = runif(1, 3*pi/2-pi/10, 3*pi/2+pi/10))
# Those squigly lines that connect text to a character are easy to draw.
# Each needs an x/y start point and an x/y end point. The library does the rest.
datalines <- data.frame(xbegin=c(1.9,4.2,2),
ybegin=c(80,70,77),
xend=c(2.1,3.9,2.8),
yend=c(88,80,68))
# Using ggplot to do the actual graphing -- an versatile graphing library for R
p <- ggplot() + geom_smooth(mapping=aes(x=workout, y =rank),
data=scores,
method="loess")
# Do ALL the generating!
# This includes putting everything together and adding the sample text we want to write.
# Of course, this text should be written using the xkcd font.
p + xkcdaxis(xrange,yrange) +
ylab("Percentile") +
xkcdman(mapping, dataman) +
annotate("text", x=2.4, y = 93, label = "There's a lot of\nroom up here", family="xkcd" ) +
annotate("text", x=4.1, y = 83, label = "Let's do 7 minutes of Burpees!", family="xkcd" ) +
annotate("text", x=2.8, y = 62, label = "I will use your face\nas a wallball target...", family="xkcd" ) +
xkcdline(aes(xbegin=xbegin,ybegin=ybegin,xend=xend,yend=yend),datalines, xjitteramount = 0.11)
```

Code language: PHP (php)

Running this in the R console generates a pretty slick graph:

Even if I don’t see myself creating loads of XKCD-style graphs, getting one made was a lot of fun.

If you’re curious about what else you can do with the XKCD library, check out the documentation.

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