Lecture 12 - Semester 2 - Take Home Message
Hi Everyone
Well, that certainly was an attack of sillies yesterday wasn't it?! But, I guess we needed it. It was pretty confusing for a first go-over. So let's review everything:
(1) We reviewed the basics of sampling and discussed the notational differences between the sample parameters and the world or total population parameters
(2) We discussed different kinds of sampling and the problems associated with the different sampling protocols.
(3) We discussed some basic probabiliy and how to define the probability P(E) that an event E would occur.
(4) We discussed how to use SPSS to draw a random sample from a dataset
We then went and examined the problem of estimation of population parameter values from samples of that population. We noted that there are two kinds of estimates, point estimates and confidence interval estimates.
(5) We looked at what a confidence interval meant and how one would define a confidence interval using the area under the normal curve
(6) We then used this argument and used the z-table to understand how to computer the z-score associated with a certain "degree of confidence" for a result. That is, "I would like to be 95% sure that my confidence interval contains the true population mean." We translated this into a graph that we then used to find the associated z-score for different degrees of confidence. We called this the z-score of confidence or zconf.
(7) Using the idea of area under the curve, we then demonstrated how we could use the z-transform equation to calculate the confidence interval formula for the population mean, based upon knowing the sample mean and the sample standard deviation. At this point, we all got very giddy and decided to go home because our brains were fried. So here are the lecture notes for today.
Lecture 12 Sampling/Estimation Lecture Notes
Have a great week everyone. We will continue this work and move into the next chapter.
Tarynn
Other things to remember:
(1) If you are waiting IRB approval, stay on top of it. Let me know if there are any problems.
(2) If you are having problems obtaining decent datasets, let me know.
(3) If you are having problems setting up your database/entering your data, let me know.
At this point you should have the following things pretty well completed:
(4) Your opening slide, review of talk slide, and your problem slide for your presentation completed
(5) You should have the material for your cover page and your introduction to your paper gathered along with your bibliographic material
Other than those individuals waiting for the IRB, everyone should now be gathering data and entering it into their database in SPSS. You should be seriously considering the questions you wish to ask and how to analyze them.