Richard Williams, Notre Dame Sociology

Sociology 63993

Graduate Statistics II

Richard Williams, Instructor

Spring 2009


NOTES This web page is under development.  Links will become live when they are ready.  Click here if you want to see the online notes and handouts from the last time the course was taught.  Some of these will be updated for this course. My notes from Graduate Statistics I are also available.

My
Stata Highlights page includes links to Stata and statistical handouts from my other courses that may interest readers. 

Stata and SPSS are in the labs.  You can also order your own personal copy of Stata through the GradPlan package.  I recommend the Intercooled Stata 10 & Getting Started Manual for $155.  Cheaper and more expensive packages are also available.  You can get by with Stata 9 if you already have it, but the data file format changed in Stata 10 so that may occasionally cause you problems if you are using an older version.

 

The following special types of files are used on this web page:

PDF Pdf files. Require Adobe Acrobat.  Get Acrobat Reader
Tbk Toolbook files. Viewing Instructions
SPSS SPSSWIN files. Necessary for doing homework problems. Can probably be adapted for other SPSS platforms. You should save these files to your local hard disk and then use them with SPSS.
Stata 9 & 10 files.  Necessary for doing homework problems.You should save these files to your local hard disk and then use them with Stata.

In addition, some files are in zipped (compressed) format.  If you don't have an unzipping program (e.g. Winzip), you can use the free PC Magazine PCDEZIP utility.

Finally, please note that the answer keys for the exams and homework differ in the amount of detail provided.  I sometimes give very detailed answers, other times the answers are much more minimal (and given the information provided I assume the student can figure out the rest).  Students should always aim for complete answers in their homework and exams.  In particular, it is hard to give partial credit when it is not clear why an error was made.

Syllabus

Readings Packet (You need a Notre Dame NETID to access these)

Example First Draft - Karen Boyd, 2002 (Used with Permission)

Example First Draft - Selected RW comments on Boyd Draft

Notre Dame's Social Research Data Services Web Page (has links to several data sets and describes support services)

Useful sites for learning about Stata and SPSS

Rich Williams' Stata Highlights Page

UCLA's Statistical Computing Resources 
RW Suggestions for Using Stata at Notre Dame 

UCLA's Stata Starter Kit

RW's Suggested downloads

UCLA's SPSS Starter Kit
Resources for learning Stata UCLA - How does Stata compare with SAS and SPSS?
The Stata User Support Page Ben Jann's estout/esttab support page (esttab & estout are great for formatting output from Stata)

PART I: In this section, we briefly review the basics of OLS regression. We talk about some of the most common issues (measurement error, missing data, violations of OLS assumptions) encountered in regression analysis.

Using SPSS for OLS Regression (Read on your own & ask questions in Lab as needed)

reg01.sav - Data file used in the SPSS Regression handout

Using Stata for OLS Regression (Read on your own & ask questions in Lab as needed)

reg01.dta - Data file used in the Stata Regression handout

Overview

Review of Multiple Regression

Homework # 1 (Due Jan 28)

sphrd.dta (Stata data file required for HW # 1)

Homework # 1 Answer Key

Multicollinearity

mulicoll.dta - Stata data file used in the Multicollinearity handout

Missing Data

md.dta - Stata data file used in the Missing Data handout

Homework # 2 (Due Feb 4)

longley.dta

missing.sps

missing.sav

missing.dta

Homework # 2 Answer Key

missing-ak.sps (adds some additional analyses to the earlier program)

hw02-III.do (Stata program for problem 3)

Measurement Error

Measurement Error Example (Supplemental)

Scale Construction (Very Brief Overview)

anomia.dta - Stata data file used in the Scale Construction handout

anomia.sav - SPSS data file used in the Scale Construction handout

Outliers

outliers.dta - Stata data file used in the Outliers handout

outliers.sav - SPSS data file used in the Outliers handout

Also Recommended: Robert Yaffee's Robust Regression Modeling with Stata (This is 93 pages long but it is basically overhead slides and hence much shorter than it at first appears to be.  Nice discussions of how to deal with outliers and with heteroskedasticity.)

Heteroskedasticity

reg01.dta - Stata data file used in the Heteroskedasticity handout

Serial Correlation (Very Brief Overview)

Also Recommended: UCLA's Regression Diagnostics Page.  Shows a lot of the techniques that are available with Stata for detecting outliers, heteroskedasticity, multicollinearity, serial correlation and other problems with regression models.

Homework # 3 (Due Feb 11)

resales.dta

resales.sav

Homework # 3 Answer Key

resales.do (Stata program for the real estate sales problem)

  resales.sps (Spss Program for the real estate sales problem)

Sample first exams and answer keys

 

PART II: This section shows how regression can be used to properly specify a causal model. We begin by introducing "the logic of causal order," which lets us understand the different kinds of causal relationships that might be present between variables. Common model mis-specifications are then addressed (e.g. omitted variables, extraneous variables, variables with nonlinear effects). We discuss how to choose between alternative causal models. Finally, we introduce path analysis as a method for causal modeling.

tbklogic.zip These are toolbook presentations which we will go over in class.  Viewing Instructions

[Optional] If you also want more conventional notes for the above material, click here and here. In class, I'll only use these notes if there is a problem with the Toolbook presentation.

Local of Causal Order, Handout 1: Variable Naming 

Local of Causal Order, Handout 2: Sample Problem, Logic of Causal Order

Local of Causal Order, Handout 3: Suppressor Effects

Local of Causal Order, Handout 4: Interaction Effects

Local of Causal Order, Handout 5: Another Sample Problem for the Logic of Causal Order

The Logic of Causal Order, Closing Comments

Homework # 4 (due Feb 25)

Homework # 4 Answer Key

Specification Error

Imposing and Testing Equality Constraints in Models

blwh.dta - Stata data file used in the constraints & group comparisons handouts

Group Comparisons: Differences in Composition Versus Differences in Models and Effects

Group Comparisons: Using "What If" Scenarios to Decompose Differences Across Groups

Homework # 5 (Due March 4)

gender.dta

gender.sav

Homework # 5 Answer Key

Interaction Effects and Group Comparisons

Models for Group Comparisons - Summary

blwh.dta - Stata data file used in the Interaction Effects handout

Interpreting Interaction Effects; Interaction Effects and Centering

drinking.dta - Stata data file used in the Interpreting Interaction Effects handout

Discussion Questions for Group Comparisons and Interaction Effects (Cover these on your own if we don't get to them in class)

  Interactions Between Continuous Variables (Read on your own if we don't get to it in class)

Homework # 6 (Due March 18)

gender.dta

gender.sav

jgqes2.sps

jgqes2.sav

Homework # 6 Answer Key

Nonlinear Relationships

Introduction to Path Analysis

Introduction to Path Analysis - Highlights

Homework # 7 (Due March 25)

nonlinhw.sps

nonlinhw.sav

Homework # 7 Answer Key

Sample second exams and answer keys

 

PART III: Here, we develop path analysis techniques more fully. We talk about more complicated models that cannot be accurately estimated through conventional OLS regression techniques (e.g. nonrecursive models). We also talk about situations where the nature of the data make OLS regression inappropriate (e.g. dichotomous dependent variables) or less than optimal.

Structural Coefficients in Recursive Models/ Evils of Standardization

Computing R Square/ Evils of R Square

Homework # 8 (Due April 8)

evilstnd.sps

Homework # 8 Answer Key

Logistic Regression I: Problems with the Linear Probability Model (LPM)

Logistic Regression II: The Logistic Regression Model (LRM)

Logistic Regression III: Hypothesis Testing, Comparisons with OLS

Using Stata for Logistic Regression (be sure to read this on your own, as it covers important details we may not go over in class)

logist.dta - Stata data file used in the Logistic Regression handout

Homework # 9 (Due April 15)

lrb.sps

lrb.sav

lrcalc.sps

lrb.dta

Homework # 9 Answer Key

Ordered Logit Models

Multinomial Logit Models

shuttle2.dta - Stata data file used in the Ordered Logit and Multinomial Logit handout

Nonrecursive Models

nonrecur.dta - Stata data file used in the Nonrecursive Models handout

Brief Overview of Manova

blwh.dta - Stata data file used in the Manova handout

Brief Overview of LISREL

 Extremely Brief Overviews of Event History Analysis and Hierarchical Linear Modeling --

Read Ch. 9 of Paul Allison's Multiple Regression Primer, paying particular attention to section 9.9 (Multilevel Models) and section 9.12 (Event History Analysis)

Homework # 10 (Due April 29)

Homework # 10 Answer Key

Sample final exams and answer keys

 

Other materials may be available upon request.