Introductory Statistics

I've finished grading and have input the scores and grades into GradeQuery. If you have any questions, please let me know as soon as possible. I"ll be submitting grades to the registrar in the next couple of days.

Thank you for all your hard work over the course of the semester. I hope that you fell more confident about quantitative analysis now. I look forward to seeing you in 713 in the spring.

Because we did not get to logistic regression in class, you should skip questions 4, 5 and 8 on Assignment 4.

I've moved the due date for the third assignment to Sunday, 11/29. Also, I've updated the PUMS2000 data so it should work for assignments 3 and 4. If you are in the sociology lab, use PUMS2000new. If you are somewhere else, download the PUMS2000 data and then open it in SPSS.

Post the summary interpretation of your results here. Remember to identify who is in your group in your response.

I've added a forum question about standard scores. Respond before T Nov. 10.

Let's say that we are interested in the problem of population density in urban communities. We decide to look at neighborhoods as our unit of analysis. Suppose the mean density for all neighborhoods in a particular city (our study population) is 375 people per block with a standard deviation of 200 people per block.

What is the probability of selecting a random sample of 100 neighborhoods from this city with:

1. a mean of 380 people per block or more?
2. a mean of 368 people per block or less?
3. a mean between 370 and 380 people per block?
   

I'm not going to make it to campus on TH, 10/8, but I will finish grading assignment 1 and post the grades tonight. I'll have written feedback for you on T.

As a group, identify one of the fallacies we've discussed, or some other point about how everyday thinking is at odds with the way that probability works, and describe how people are often led to the incorrect conclusion based on a misunderstanding about probability. For example, you might consider the gambler's fallacy as an explanation of why gambling is so popular. Explain the logic of everyday reasoning and how a correct understanding of probability would lead to a different conclusion. Post a one paragraph summary of your discussion as a comment to this page.

I have copies of the probability reading (Handout A on the schedule) in my office. Stop by during office hours to pick up a copy before our next class meeting.

We'll be using SPSS for data analysis this semester. I've created a couple of datasets for us to work with, and I'll add more as the semester goes along. If you have access to SPSS off campus, you can use links on this page to download a copy of the data files for your own use. Links to the SPSS system files are in the comments, below.

CBSNYT_May2007
This is a public opinion study done by CBS News and the New York Times. Most of the major news organizations do regular public opinion polling.

PUMS2000
This is a random sample from the public use Census 2000 data.