Tableau

How Do 40 Times Change From Round to Round? A Study Using a Flimsy Question to Show Off a Cool Tableau Feature

In the months leading up to the NFL Draft, potential players are poked, prodded, and tested in just about every imaginable way.  Perhaps the most well-known of all of these measurements taken by teams is the 40-yard dash, which is the agreed-upon way to test speed of players.

Today we are going to take a look at how the average 40 times change by round.  Is there a direct relationship between draft round and 40 time?  Let's find out!

To begin, I have connected Tableau to a table showing 40 times for all draft picks from 1999-2015. 

Once the data was uploaded, I created a simple bar chart showing average 40 yard dash times by position.

Once the basics were there, I color-coded the positions and grouped them to clean up the view (Offensive Linemen, Defensive Linemen, Defensive Backs, and Linebackers were put into their own categories, and special teams players were removed).  This resulted in the view below.

Ok, it at least looks better than Excel now.  But this doesn't answer the question we originally posed, and it certainly is not a cool Tableau feature!  So let's dive deeper.  How can we show the round-by-round comparison? 

Pages!  Pages is a new-ish feature for Tableau that allows us to animate our graphs based on an attribute.  In this case, I will use the round of the draft.

To do this, I just drag round onto the Pages card as is shown below.

By doing this there is now a new control under our color legend, that will allow for scrolling the graph by draft round, and even allows animation!  The control, and an explanation of its features, is below.

These controls allow us not only to scroll from round to round, but to let Tableau do it automatically for us!  Let's take a look at our updated graph (first round and seventh round).

If you look closely you can see some differences, but it doesn't really "pop".  Let's make a few more small changes (fix the axis, clean up the titles). 

There you have it!  We can now clearly see the rise in times from the first round to the seventh.  This is even more apparent when you animate the graph using the page feature.

I hope you enjoyed this demo of the page feature thinly veiled as draft analysis! 

Author: Chris Bick

Tableau and Modified Paretos of NFL Injuries (or Why I am Okay with a Desk Job)

It is no secret that playing in the NFL is a physically demanding job, and along with that comes the unfortunate side effect of injuries.

Today we will take a bit of a break from the NFL Draft and will look into creating a cool-looking Pareto Chart of the current list of NFL injuries, including some key prospects.  At least I think it is cool-looking.  Don't judge.

In order to map injuries, the first step is to obtain data on who is injured.  This was done from RotoWorld (thanks guys!) and compiled in Excel.  It looks like this.

Exciting, right?  and that is just 20% of it!

Exciting, right?  and that is just 20% of it!

Once data was collected, the next step to making the pareto is to map the various body parts listed in the injury report onto an image.  This is where the Tableau magic happens. 

The next step is to create a new tab in Excel that you can use to map the body parts.  Once you get the size of the image you're using (in my case it is 289x525) into the table (this is done to force Tableau into the correct data conventions, you don't need it otherwise).

Now, we can open Tableau and load in the data set.  The tables created will need to be joined, so do that now.

The next step is to load our player image in as a map.  First, make sure your X and Y columns from the mapping table come in as measures.

Capture.PNG

Then, you will follow the path shown below, and fill in the screen with your corresponding picture size (again, mine is 289x525, but yours will likely differ).

Capture.PNG

Once this is all done, click OK.  Then, right click and drag X to columns and Y to rows as unique values.  This should load your picture onto the screen.

Now, you will need to plot your data points.  For every point to be mapped (in my case, for all body parts with an injury), right click on the area and select Annotate-->Point. 

Example: point annotation for abdomen injuries

Example: point annotation for abdomen injuries

Copy the corresponding X and Y values into your table.  Repeat until all points are plotted, then save your data file.  It should now look comparable to this.

Now we're on the home stretch!  Add the item being counted in the Pareto to the Size Card, adjust coloring and shapes as you desire, and you're all set.

Capture.PNG

Hmm, our football player appears to have lost an arm.  Let's fix that.  Go back to the Map-->Background Images menu and click edit the background image you created earlier.  On the second tab, there is a check box that forces the entire image to be shown.  Select that to correct the issue.

Voila!  The entire Pareto Chart is now shown.  The only steps remaining are to adjust the title and Tooltip, add a filter by position, and hide the axes.  Let's have a look at the finished product.

I'll be back next week with another Tableau nugget!

Author: Chris Bick