"Obvious is the most dangerous word in mathematics." -- (Eric Temple Bell ) PAPPUS (ca 300): An excellent mathematician who lived in Alexandria, Pappus attempted to rekindle interest in the mathematical works of the Greeks. This was not an easy task, since Christians had destroyed much of the ancient Greek documents, but Pappus managed to create his Mathematical Collection which cites or references over thirty different ancient mathematicians. Much of our knowledge of Greek mathematics has been derived from the works of Pappus. Why did Herkimer have trouble making a phone call to the zoo? Answer: Because the lion was busy. Herky 's friends: JUSTIN TIME ...this guy always arrives at the very last minute. LEE KEEROOF ... a repairman who prevents rain water from dripping into your house. Reading: Section 3.3, pages 144 - 159 plus SUMMARY (Page 160) and CHAPTER REVIEW (Pages 164-165). Exercises: 3.39 (Page159), 3.49 (Page 163).

You are in Section 3.3.

Residual plots can be very useful in determininghow well a regression line "fits" the data. A residual is thedifference between an observed value and a predicted value.

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Text:
The Practice of Statistics, by Yates, Moore, McCabe. New York,W.H. Freeman and Company, 1999. (ISBN 0-7167-3370-6)

Supplemental books:
The Cartoon Guide to Statistics, by Gonick and Smith. NewYork, HarperCollins Publishers, 1993. (ISBN 0-06-273102-5)
How to Lie with Statistics, by Darrell Huff. New York, W.W.Norton & Company, 1982 (ISBN 0-393-09426-X)