carprice
31. New Car Prices. Kelley's Blue Book (www.kbb.com) publishes data on new and used cars. The following table contains the fair market value for five new 2013 and 2014 vehicles (data recorded July 2014). We are interested in the difference in price between the 2013 models and the 2014 models. Assume that the population of price differences is normally distributed.
| Toyotay Camry |
Honda Civic |
Ford F-150 |
Chevy Corvette |
Tesla Model S |
|
|---|---|---|---|---|---|
|
2014 (sample 1) |
$20,672 | $17,069 | $24,362 | $45,684 | $68,738 |
|
2013 (sample 2) |
$20,284 | $16,499 | $22,674 | $44,021 | $68,674 |
10.1.31
Differences: $388, $570, $1688, $1663, $64 (a) and (b) versus . Reject if the . = 0.0301463228; The is , so we reject . There is evidence at level of significance that the population mean of the differences in price of cars is greater than 0. That is, there is evidence at level of significance that the 2014 models of cars are on average more expensive than the 2013 models of cars.