- In Example 1 3 In The Textbook The Least Squares Line Of Best Fit Was Obtained From Statistical Software And Was Given 1 (86.96 KiB) Viewed 442 times
In Example 1.3 in the textbook, the least squares line of best fit was obtained from statistical software, and was given
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In Example 1.3 in the textbook, the least squares line of best fit was obtained from statistical software, and was given
In Example 1.3 in the textbook, the least squares line of best fit was obtained from statistical software, and was given as price = 20.81 – 0.1198 mileage In the example worked in the book, the luthors showed that the predicted price for the first car in the data set was $11,800. Whereas the actual price for that car was $12,000. This means the prediction was off by $200, and in particular, the actual value was slightly higher than the predicted value. Let's work a similar style problem with a different value from the data set. This time we will use the twenty-third car in the data set. This car had a mileage value of 139.4 (139,400 miles) and a price value of 5 ($5,000). The fitted line would predict the price to be price = 20.81 – 0.1198(139.4) = 4.1 The residual would be price-price = 5 – 4.1 = 0.9 which shows that the actual price is a bit higher than the predicted price. Practice Problem: To help solidify your understanding of this model, repeat this analysis with the seventeenth car in the data set. For this car, report the observed values: • the mileage value is 68.4 which means 54.9 x miles • the price value is 13.5 which means $ 123.3 Х For the mileage from this observation, the model would predict a price value of: price = which has a residual of price-price