*Click on this picture to see it larger in a new window.*

We all know that a Super Bowl commercial costs a ton of money. What about a World Series commercial? If you were representing a company that wanted to buy World Series commercial time over the next several years, how much should they pay? We know that a 30-second commercial ad for the Super Bowl costs $4 million and reaches about 108 million viewers. Based on the value of a Super Bowl commercial, consider the cost of future World Series commercials. *Note: the 2013 World Series averaged 14.9 viewers per game. You might consider using this info when using this lesson.

Show the graph to your class.

- What do you see? ... general trend, decreasing viewership, looks roughly linear?
- What do you wonder? ... will it continue to decrease?, why the decrease? When will it reach zero?

Students will need to predict viewership from 2013 to 2017. How? You can expect different levels of sophistication based on grade level ... reasoning, estimating, rough line of best fit, more accurate best fit with Excel or graphing utility. Check out our graph and sliders on Desmos. How can we calculate the cost based on Super Bowl costs? ... proportional reasoning? According to your model when will World Series viewership approach zero? Will it ever reach zero? What are the limitations of your model?

If you are focusing on a line of best fit, let students determine that without technology first. Might be good for them to do on their own, then compare with a neighbor. How do slight differences in the line affect future predictions? After creating their own by hand have them play around with the Desmos graph and its sliders. Students can also look at residuals, number of points below and above the trend line and consider values within a certain percent range of the line of best fit.

This data in this task is linear, but does not produce a correlation coefficient terribly close to 1. Want to explore some data with a correlation closer to 1? Check out the data and graph at Desmos that compares share and rating. This data is in our Excel file and there are questions to go with this task at the Desmos link.

A big thank to our friends at Desmos for the help with the graphing applications for this lesson!

CCSS: 8.SP.1, 8.SP.2, 8.SP.3, HSS.ID.B.6

WorldSeries-viewership-and-ads.pdf Viewership-data-since-1973.pdf

For members we have a Word doc, solutions, and an Excel file of the charts and data.

WorldSeries-viewership-and-ads.doc WorldSeries-viewership-and-ads-solutions.pdf