Stat Test and Hints for Problem Set #3

We took our stat test today. The highest grade was an 84% and it was actually achieved by multiple students - nice job! The lowest grade was a 23%. If you want to ZAP a test that's completely fine, but remember, you have to STUDY first. Good grades in classes (ESPECIALLY college level classes) don't happen by pure luck. Actual effort is involved.

Below are some hints that you might find helpful for the problem set that's due tomorrow:

Problem1:
Part A: Only one answer is correct. The other three are false. Full credit will be provided to those who give an explanation WHY.
Part B: This is a GREAT question - really shows if you understand std. dev. or not. You must pick 4 numbers between 0 and 10. They can be the same, or different. Basically, I want to know that, in order to minimize std. dev (so sx is as small as possible), what should all your numbers be that you're picking? What must be true about these four numbers to make the std. dev. small? Remember, std. dev. is the distance from the mean - the more different your numbers are, the bigger your std. dev. becomes....
The reverse is true for making the std. dev. as large as possible.
Part C: A "resistant measure of spread" means that, if we stuck an outlier into the data set, the spread wouldn't really change much/at all. Recall that the IQR is the middle 50% of the data....
Part D: Remember that means are calculated by adding up all the numbers and dividing by how many there are. That doesn't necessarily mean that there must be equal amounts of men and women in this company.

Problem 2:
Another GREAT question. Think of a graph that you can make with the given information (for both male and female doctors) that would help you to determine the shape of the data. Hint: it's NOT a Normal Curve. Why? Well, just because we have a mean and a std. dev, that doesn't imply normality. EVERY quantitative data set in the world has a mean and a std. dev, but that doesn't imply that EVERY data set is also symmetrical (which the Normal Curve is). So, given all that information, what other graphs can be created?

Problem 3:
Part a: Find the standard deviation using the formula we used in class. There should be an example of this in your notes.
Part b: Remember how to interpret: also in your notes. IN THE CONTEXT OF THE PROBLEM! INCLUDE UNITS FOR FULL CREDIT.
Part c: This one you should be able to figure out on your own, but my advice is to BE SPECIFIC. A one-sentence answer isn't going to cut it here.

If you write I love Math at the top of your problem set tomorrow I will give you 5 bonus points.

Problem 4:
Part a: TITLE, LABELS, AND SCALE
Part b: CUSS
Part c: Think about the shape of your boxplot in regards to what we talked about in class
Part d: Again, be specific. More would change than just the spread of the data, although that's certainly part of it. Remember to tell me WHY along with the WHAT.

Problem 5:
Graphically means make some type of graph that makes sense given the type of data. Numerically means 5-number summary. Summarize your findings means write a paragraph, using SPECIFIC language, units, and such to talk about what you SEE.

Good luck!