| Hand in Monday: If you didn't, p. 277, 11.6 sampling distribution of exam scores Do a and a modified version of b; Do b this way. Close your eyes and put your finger down somewhere on table B (Don't use row 116!! unless you land there.). Start reading the table where your fingertip lands. Record your sampleof 4, and find xbar for your sample. Now Repeat part b, to get a total of 3 values of xbar. (You can just keep reading the table where you left off, or you can put your finger in a different spot). Record your 3 xbars, Make a dotplot of your 3 xbars and bring the values to class to be compiled with everyone else's.. = = = = = Ch. 11--= = = = p. 272 11.1 caffeine (Param./Stat.) p. 272 11.2 voters(Param./Stat.) p. 275, 11.4 means in action (LLN) p. 275, 11.5 insurance (LLN) Hand in the ones above. (Re)Read the ones below, will be part of next HW. DIST. OF XBAR(S) These problems use only the mean and standard deviation. p. 280, 11.7 (Teen cholesterol ) p. 280, 11.8 (lab measurements) For (b) they mean "what should n be?' These problems use the "sample mean of n independent observations from a normal distribution has a normal distribution." theorem (p. 278) p. 280, 11.9 NAEP math scores (n = 1, n = 4) p. 290, 11.37 and 11.39 Pollutants in auto exhausts For 11.39: You might want to know L so that if you tested your 25 cars and found a high value of x-bar, you would be able to compare it with L; if it was greater than L, you would go back to the manufacturer and say "I believe you sold me a batch of bad cars, because the chances of getting an average emission level this high if the exhaust system is working properly is only 1 in 100. It is more reasonable to believe the exhaust system is not working, than that we "are" that 1 in 100 possibility." p. 289-90 11.36 and 11.38 Glucose testing If we use this cutoff level L to say that people (with a mean of 4 tests) over L "have diabetes", then the chances of declaring that someone "has diabetes" when they really are OK (with mean 125mg/dl) is .05. .05 or 5% is the chance of a "false positive" using this protocol, when the real mean is 125. These problems use the Central Limit theorem (p. 281) p. 185, 11.10 What does the CLTh say? p. 286 , 11. 12 SAT scores, n = 1 and 70 p. 286, 11.13, insurance (Hint: find P(Xbar> $275)) p. 298, 11.41 auto accidents p. 298, 11.42 airplane overloads (Hint: to do the problem you have to assume all the seats are taken. Maybe not a reasonable assumption, but if there are empty seats, there's likely not a problem with overweight.) |
Read, to discuss |
Optional - - - - p. 272,11.3 Bearings (Param./Stat.) |
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