## Wednesday, January 21, 2015

### The Probability of Madness (original)

The Probability of Madness
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 do that for 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 15th quiz, and he receives a score of zero. 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.
Why can’t I just write down the answer? What’s with all this complete sentence crap? It’s statistics not English. I miss pre calc. 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.
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 answer? 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 keeping junk food in the house. I’m trying to be healthy. Whatever, popsicle for dinner I guess… God, I’m weak.
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)
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.
Two problems and an eternity later…
1.54 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.

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