Sunday, 21 January 2018

Data Visualization Analysis: NFL Championships Per Year of Existence

On October 2011, a user named Andrew posted an article on graphgraph.com where he showed the percentages of each NFL team winning either the Super Bowl or an NFL championship per the number of years that team has been in existence. He expressed the data on a normal bar graph with each team listed by the highest percentage of championships per year. Teams that had identical records were listed by oldest to newest.

The graph provides a great deal of information, but because all thirty-two teams are listed, the information is very compressed and hard to see. It's easy to tell that the Green Bay Packer's bar is by far the longest while the teams listed below Arizona have not won championships, but actually reading the percentage for any given team is difficult.

Omitting the teams have not won a Championship and noting that the bottom of the graph, would allow for the graph to be more easily understood and visible. Similarly, utilizing two bar graphs, one for the AFC and one for the NFC, would improve comprehension and make the percentages easier to see. Expressing the information this way would benefit users by illustrating which conference has historically been stronger.

It is also difficult for non-NFL fans to understand how many championships a specific team has won or the number of years a specific team has been in existence. This information is not shown on this graph. For these reasons, I think that expressing the information on a scatter plot with time on the x-axis and the number of championships on the y-axis, would make for a more informative graph. Expressing the data in this way would show more information about a team's history. The graph would however, be very spread out, as certain teams have been in the NFL for almost 100 years.

The graph does do a lot of things right. It clearly tells which teams have a better record based on the length of the bars and the graph starts at zero which makes sure that the information is not misleading. The bars are also shown with each team's primary or secondary colour. Although some colours are very similar (Patriots and 49ers), this is a helpful touch that adds to the graph.

This graph was created in 2011, so it does not show the changes to the records of the teams that have won the Super Bowl in the last 6 years. The Patriots winning two Super Bowls would greatly improve their record, while the Seahawks would no longer be lumped with the teams that have never won. This is not a problem of the graph, I just wish that it would be updated to reflect these changes.

Overall Andrew's graph is very informative, but would benefit if the information could be presented in a more visually understandable way.

7 comments:

  1. I have to agree with most of the improvements you recommend in your blog post (the scatter plot would be a bit too awkward as you conceded). I also noted the point you made about colour of the bars in the graph - if he eliminated teams that haven't won the Super Bowl, or separated AFC and NFC colours would not get confusing! Good post!

    ReplyDelete
  2. Teams that haven't won yet shouldn't be on the chart, as it just makes the bottom half of the chart blank. As you also mentioned, it would be nice to see the amount of championships, to see if teams have sustained their good (or bad) numbers. It would be hard to visualize, but it would also be interesting to see how many teams were in the league when the championships were won, to see whether certain teams can only win with less competition.

    ReplyDelete
  3. I also agree that teams that have not won a championship should be left off the chart because it makes the bottom half of the chart useless. Even though a chart should not heavily rely on numbers alone the percentages provided in this graph are so small they are barely visible. I agree that making the percentages more visible would improve this graph.

    ReplyDelete
  4. Hi Marcus,

    You are right with your assessment. As a non-NFL fan, I did not quite understand what it was trying to say. I also agree that the use of the same or strongly similar colors is confusing to the eye, as one may think of the other team.
    Perhaps to simplify the data, non-winning teams should not be depicted. Instead, the author could focus on the teams most likely to win the Super Bowl or other championships.

    ReplyDelete
  5. Eliminating the teams that have not won would make the chart less confusing. Also, switching to a scatter plot would be helpful to view a teams history even tho it some teams may have a long history.

    ReplyDelete
  6. I agree that the graph is informative and it for sure could have been presented in different way that would be easier to understand. Teams that have not won a championship should not have been put on the chart because it makes part of the chart useless.

    ReplyDelete
  7. I agree with the points you made Marcus. The chart itself was very heavy in data and made it difficult to view. The changes you recommended would have been able to give the readers a clearer understanding of where each team stands. Great job

    ReplyDelete