Overrated
How much confidence should you place in online ratings?
Students will
- Summarize the distribution of product ratings using different methods, including the mean and the mode
- Discuss which methods of summarizing ratings are the most/least trustworthy
- Understand that the average rating stabilizes as the number of reviews grows, and that average ratings of products with a small number of reviews are less trustworthy
- Discuss what a website can do to ensure that its reviews are helpful
Before you begin
Students should have experience adding and subtracting integers, and should be able to calculate simple ratios. The most complicated mathematical questions involve averaging, and prior experience calculating averages is assumed.Common Core Standards
Content Standards
Mathematical Practices
Downloads
Shoutouts
Amazon.com, NPR's Planet Money
Related Lessons
Ballot Boxing
How do the rules of an election affect who wins? Students calculate (as a percent) how much of the electoral and popular vote different presidential candidates have received, and add with integers to explore elections under possible alternative voting systems.
Harmony of Numbers
Why do certain pairs of notes sound better than others? Students use ratios and fraction division to explore what makes two notes sound good or bad when played together.
Nothing But Net
How do you determine the best scorer in basketball? Students compare LeBron James and Tyson Chandler in various ways, from total points, to points per game/minute, to a new measure called net points in order to decide.
Leonardo Numbers
Are there numbers hidden in nature? Students use the Fibonacci Sequence and Golden Ratio to uncover the mathematical mysteries of the universe.
My Two Left Feet
Should shoe companies sell left and right shoes separately? Students collect survey and measurement data, construct bar graphs, and discuss distributions and measures of central tendency in order to figure out whether shoe companies should necessarily be selling their products in same-size pairs.
Origin Stories
How can we compare similar items? Students plot points with positive and negative coordinates in order to compare items across two different attributes. They use the plots to decide which item is the “best” in different scenarios, and discuss whether or not negative numbers always represent the “opposite” of positive numbers.
Bookie Nights
What's the best way to bet on the Super Bowl? Students add and subtract positive and negative numbers to determine which bets have been the most effective and consider the best ways to win big on the big game.
Downside Up
Is there an upside to negative feelings? Students use integers to compare good and bad days and use absolute value to explore what happens when we reinterpret negative moments in a more positive light.
Jenius!
How does the what we see affect our happiness? Students explore the concept of the jen ratio – the ratio of positive to negative observations in our daily lives – and use it to discuss how the content we consume and the things we observe influence our experience of the world.
Wealth of Nations
How is wealth distributed in the United States? Students use measures of center, five-number summaries, and box plots to examine different distributions while digging into one of the most important economic and political issues facing any nation.
