The Probability of Madness (Revised Final)

1.27 Joey’s first 14 quiz grades in a marketing period were

86           84           91           75           78           80           74           87           76           96           82           90           98

(a) Use the formula to calculate the mean. Check using “1-Var Stats” on your calculator

Wow that’s an easy one. I hope she doesn't want me to show my work, I hate when math teachers make me prove my brilliance step by step on the simplest problems. Where’d my calculator go? I swear I had it like five seconds ago. Oh, there it is.

A) 85.

(b) Suppose Joey has an unexcused absence for the 15^th quiz, (Ooooohhhh, playing hookie again Joey. Bad seed.) and he receives a score of zero. (Well! That's a little harsh.) Determine his final quiz average. What property of the mean does this situation illustrate? Write a sentence about the effect of the zero on Joey’s quiz average that mentions this property.

How does this affect his quiz average? Right now, I'm far more worried about the effect that this will have on his emotional health, given his fragile condition and propensity for missing important quizzes in school... and why can’t I just write down the answer? What’s with all this complete sentence crap? It’s statistics not English. I miss precalc. Ms. Nastri never made me write complete sentences.

B) 79, this illustrates that the mean is not resistant to outliers. The zero is an outlier, and lowers Joey’s quiz average by 6 percent and will likely lead to a life of crime given that his every error is hurled in his face and announced to the world in math books across the country. 

c) What kind of plot would best show Joey’s distribution of grades? Assume an eight-point grading scale (A: 93 to 100; B: 85 to 92; etc.). Make an appropriate plot, and be prepared to justify your choice.

What if I don’t want to justify my choice?  Can’t you just take my word for it? This isn't my only class you know.

C) A stem and leaf plot, because it’s a medium amount of data, it will put the data in order, and allow me to access the original data from the plot.

7     4,5,6,8

8     0,2,4,6,7

9     0,1,3,6,8

2 problems and half an hour later…

1.30 Last year a small accounting firm paid each of its five clerks $22,000, two junior accountants $50,000 each, and the firm’s owner $270,000. What is the mean salary paid at this firm? How many of the employees earn less than the mean? What is the median salary? Write a sentence to describe how an unethical recruiter could use statistics to mislead prospective employees.

I’m hungry, but I don’t have time to cook. Screw you, Stats Homework!! Ooooo... Popsicles! I thought I talked to my dad about not keeping junk food in the house. I’m trying to be healthy. Whatever, Popsicle for dinner I guess… God, I’m weak... but then again, they are made with real fruit. They can't be that bad for you; they're practically health food.  

Mean= 60,000, 7 employees earn less than the mean. An unethical recruiter could present the mean to make people think that they would receive more money than they actually would, because the mean is greatly affected by an outlier—270,000. Is the recruiter really responsible for someone stupid enough to think they are going to rake in 60 Gs as a mail boy? 

Two problems and 1 hour later…

1.40 Which measure of center and spread should be used for the following blah blah blah blah blah blah blah?

I think this work is actually making me dumber! I CAN FEEL MY IQ PLUNGING. Fortunately, my starting point is so high I can take a 30% loss and still be sitting pretty.

Two problems and an eternity later...

.54 The mean and standard deviation measure center and spread but are not a complete description of a distribution. Data sets with different shapes can have the same mean and standard deviation. To demonstrate this fact, use your calculator to find the mean and standard deviation for the following two sets of data. Then make a stemplot of each and comment on the shape of each distribution.

I think the shape of each is deplorable. They are pudgy, pale and in desperate need of a few hundred hours on some gym equipment. A better diet wouldn't hurt either... Knock off the Twinkies, Boys!

Unfortunately, the quantity of remaining homework > the amount of time left in the day. I JU-UST WANNNA TAKE A NA-AP!!!!!!!!!!!!!!!!!!