Introductory Quantitative Methods

This course introduces the graduate student to basic methods of empirical inquiry in the social sciences. The overwhelming majority of studies that test hypotheses, empirically fit models, produce predictions, or estimate policy impacts are based upon some form of quantitative or statistical analysis. This course will provide a basic introduction to statistical methods for political scientists and policy analysts. The course will provide an introductory foundation in statistical inference, enabling the student to become a competent producer of basic statistical research. In addition the skills acquired will enable the student to become a somewhat more sophisticated consumer of more advanced research methodologies.

The level of mathematical treatment is somewhat more advanced than an undergraduate class, but will still be moderate (high school algebra). We will not dwell upon derivations. [While it is desirable to have had some prior coursework in statistical inference, this course does begin with the basics. Statistical inference seems to require several repetitions to sink in, so Statistics 211 (or its equivalent) is considered a prerequisite. The student taking PS601 without having had a prior stats class will find that the class will be somewhat more difficult, but can be survived. Please discuss this with me if you have not had any prior coursework in statistics.]

The basic organization of the course is: (1) a general introduction to research methodology, (2) descriptive statistics, their use and interpretation, (3) the essential elements of probability, (4) the foundations of statistical inference, (5) and finally an overview of selected hypothesis tests.

Course Requirements

The course requirements are two in-class open-book examinations and a moderate number of assignments (~12).  The 'midterm' will be late in the semester due to the desire to spread the more mathematical elements across two tests rather than place it all in the final. No seminar paper is required, however, the assignments will contain written work in which clarity and sophistication of presentation are critical elements of the assignments. In addition, the assignments will be required to be turned in as Web pages. I will provided detailed instructions on how to create web pages and how to accomplish this task. Don't worry...It's easy!
 

• Elementary Statistics in Social Research. by Jack Levin and James Alan Fox. Allyn and Bacon. (2006 - 10th Edition) [Order]
• Quantitative Methods in Practise. Davids A. Rochefort (Ed.). CQ Press (2006) [Order]
• The Lady Tasting Tea by David Salsburg. Holtzbrinck Publishers (2002) [Order]
• Selected Pages on the World Wide Web (See Course Outline Below)
  • Sites used in this syllabus
    • Rice Virtual Lab in Statistics:
      • Hyperstat Online by David Lane
      • Simulations and Demostrations
    • The World of Visual Statistics
      • Visual Statistics with Multimedia
  • Some General Sites:
    • Research Methods Knowledge Base by William Trochim
    • Statnotes: An Online Textbook, by G. David Garson
    • StatSoft: Electronic Textbook
  • Also, for those inclined to mathematics and puzzles, Cut-the-Knot

Also of some value, but not required are:

• Statistics with Stata. Lawrence C. Hamilton. Thompson-Brookes/Cole. (2004) [Order]
• The Elementary Forms of Statistical Reason. by R. P. Cuzzort and James S. Vrettos. St. Martins (1996 - Out of Print) [Order]

Additional Features

A few other articles and books will be placed on reserve in 316 Woodburn.  In addition there are several Web assignments in the course outline.

Also, my class notes and presentation slides will be available via the Web.  These notes are under development and will change constantly throughout the semester.  I expect them to change just before each class.  I strongly recommend against extensive printing of the entire file! [Instructions on saving paper when printing Powerpoint.] I recommend printing just before class. I will frequently revise these notes right up until 9:55.

• PowerPoint Version of Notes (recommended if you wish to print them)
  • Part I
  • Web Page Design
  • Logic
  • Microcomputer Architecture
  • Statistical Decision Making
  • Probability
  • Part II
  • Regression Slides

A Word about Computers

All of the assignments for the course may be accomplished with either Microsoft Excel, Corel's Quattro Pro, or Lotus 123 if it involves spreadsheets, or SPSS, SAS or Stata if it uses statistical packages. In addition, all written assignments are required to be posted as or linked from web pages. Some assignments may be spreadsheets, while others will require the use of a Web page editor. Instruction will be provided on how to create web pages for those who have never done so.

If you wish, you may elect to use your own graphics, spreadsheet, or statistical software. I will be, however, be unable to provide support except for these three packages Excel and Stata. To facilitate the assignments, I will provide some basic instruction in both Excel and Stata. Students have generally found spreadsheet software to be relatively easy to use and it also provides a powerful graphics 'toolkit'. Supplementary instruction on its use will be provided. I encourage you to become comfortable with computers to whatever degree you can. . Basic computer literacy will be an increasingly critical component of job placement.

Free software used in course.  Please download at your leidure:

• NVU (web page editor - Windowes, Linux and Mac versions available)
• Filezilla (FTP file transfer propgram)

Students with Special Needs

Social Justice Statement

Course Outline with Readings (* = Recommended)

This is an initial reading list. I may add more as the semester goes on.

Statistics Homework Assignments for PS601

All of the statistics assignments for the course may be accomplished with either Excel and Stata 9.0. If you wish, you may elect to use your own graphics, spreadsheet, or statistical software. I will, however, be unable to provide support. To facilitate the assignments, I will provide some basic instruction in Excel. Spreadsheet packages are quite easy to use and also provides a powerful graphics 'toolkit'. Supplementary instruction on Excel will be provided. I encourage you to become comfortable with computers to whatever degree you can. They are becoming increasingly important and useful, and this trend will intensify substantially over the next few years. Basic computer literacy will be an increasingly critical component of job placement.

• Name your Table of Contents web page portfolio.htm (so I can find it)
  • Put a mailto link on it with your email address.
  • Make it graphically presentable
• Make your assignments readable.
  • Spend some time cleaning up and formating your assignments to be as clear and aestheticaly appealing as is reasonable.
• Please put your name on the top of your assignments, so that when I print it I will know who's it is!
• Always print preview your web page. I will have to print them to give you feedabck, so try not to waste too much paper. It is easy to have spreadsheets print too wide and be unwieldy as a result
• See the my sample PS601Portfolio.htm page.
• You may use any web page editor
  • I will give some basic web page development instruction using Symantec's Visual Page

These assignments are still in draft. They will be modified before assignment.

Assign #	Assignment Name	Points1	Recommended Software	Description of Work Required	Due Date2
1	Acquiring Data from the Web	6/4	Netscape & Excel	5 spreadsheets	2/15
2	Measures of Central Tendency and Dispersion	6/4	Excel	spreadsheet	2/22
3	Stem-and-Leaf Plot and Histogram	6/4	Excel	Graph + Paragraph	3/1
4	Pie Graph	6/4	Excel	Graph + Paragraph	3/8
5	Bar Chart	6/4	Excel	Graph + Paragraph	3/8
6	Line Graph - Time Series Plot	6/4	Excel	Graph + Paragraph	3/8
7	Converting Nominal Dollars to Real Dollars (Controlling for Inflation)	6/4	Excel	Graph + Paragraph	3/15
8	T-Test	8/2	Excel	2 Paragraph	4/5
9	Two-sample t-test	8/2	Stata	2 Paragraphs	4/12
10	Regression	16/4	Stata	1-2 Pages	4/26

1. The point totals reflect points for content/presentation. How you the display the information is an important part of getting your point actross. 6/4 means 6 points for content plus 4 more for presentation for a total of 5 points.

2. These dates are highly tentative.

Description of Assignments

The following is a description of the assignments for PS 601. Several of them require that you select your own data to make some point. The Statistical Abstract of the United States (SAUS) is available online to assist you in finding data. You might also try a few data sources available on the PolyCy Guide 

Using MS Internet Explorer and Microsoft Excel (or your own favorite Web browser and Spreadsheet) find data for that you can use for the next several assignments. These "data sets" should be for a number of cases (e.g. 50 states,) and should measure some political variables of interest to you. I would like for you to acquire this data from the Internet, so I suggest that you start with the Statisitical Abstract of the United States.

Because you will need several different sets of data, you can make this a "Data Scavenger Hunt". You need to find the following general types of data:

• Two 50-state sets of data
• some data that is monetary (measured in dollers) that spans at least 10 individual years (e.g GNP, per capita income)
• A set of data that has between 4 and 10 cases (e.g voting returns by candidate)
• Another set of data that consists of a set of pewrcentages of a whole (e.g voting returns in % of votes by candidate)

Save these, and their web addresses to your disk/drive. You will need the data, and its reference, later!

One of these 50 state data sets you will need to turn into a dataset for a statistical package. In order to do this, you need to:

• Remove extra labeling
• Give data columns "variable names" of 8 characters or less using only letters, numbers, and the characters "-" and "_".
• Remove blank lines
• remove any extraneous text
• Save as Excel Spreadsheet

In order to facilitate this, I have set up some basic instructions for capturing data from a Web Source. Please follow them for this assignment. The end product will be a data set saved on disk for use with Assignment #2.

Goals:

1. Use Windows XP
2. Learn fo find a variety of data sources on the Web.
3. Lern to save the URL shortcut to return to the data at a later time.
4. Learn to capture data from an Internet data source.
5. Find and execute Excel within Windows.
6. Learn how to move around inside Excel and examine the layout of the software.
7. Learn to use the Button Bars.
8. Enter data in spreadsheet.
9. Learn to convert text data to numeric data, if needed
10. Learn to remove extraneous 'stuff' from data sources/tables to make a dataset.
11. Save spreadsheet data and return to it later.

For full Content points: At least one variable, with row labels (or row number for ID). Cell entries for data are numbers - not text. It must be 'cut-and-pastable' for Stata, or readable by StatTransfer.

For full Presentation points: No extraneous rows or labeling, no fancy formating. Nothing outside what is required to be read as a data set.

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Assignment # 2 Modeling compound growth 

In this excercise, you will develop a scenario or model that will teach you how to use a spreadsheet to model a process.  The particular process I want you to be familiar with is compound interest.  Additionally, you need to look at information on the existing social security program to estimate what you will collect in retirement from it. See SSA's Calculator (which is an online simulation similar to this one!).

You are to develop a retirement fund estimator for yourself, calculating several assumptions.  In order to complete this exercise, you will need to use estimates of the following information.  Note that some assumptions can be either a % per year or a specific/variable $ amount - your choice.

1. Your starting salary ($)
2. Your expected rate of salary increased (% or $/year)
3. The number of years you plan to work (n) (or retirement date.)
4. The starting date for contributions to your retirement fund (year)
1. A second scenario with a different starting date. (Just a second column)
5. The rate of interest on funds you put into retirement (% or $/year)
6. The rate that you will withdraw funds from your retirement account after you retire (% or $/year)
7. The annual or monthly $ amount you expect to receive from social security ($/year)

Use reasonable guesses, not just what you'd like. Perform the calculations rather than using the @Functions. Then make the spreadsheet presentable. The bottom line is your estimate of your annual retirement income. At this point, you do not need to worry about inflation.  We will return to that later.  For a similar example, look at this car loan calculator.

You may template your calculator from this example.

Use labels. Explore the fonts. Make the page you write well formated for printing! This exercise is designed to get you used to Windows and a Spreadsheet as a calculator.

Goals:

1. Use Windows 3.x or Windows 95
2. Find and execute Excel within Windows.
3. Learn how to move around inside Excel and examine the layout of the software.
4. Learn to use the Button Bars.
5. Enter data in spreadsheet.
6. Save spreadsheet data and return to it later.
7. Learn to construct formulas.
8. Learn to construct labels.
9. Learn to visually enhance your presentation.
10. Learn to print output.

Assignment_3 Frequency Histogram and Stem-and-Leaf Plot

Using Stata 8.0, produce a Stem-and-Leaf plot and a Frequency Histogram using the data that you collected in assignment 1.
Goals:

1. Input a data set into Stata
2. Learn how a stem-and-leaf plot shows the shape of the distribution while preserving the data.
3. Learn how to generate a Frequency Histogram using Stata.
4. Successfully caputure the image of the graph and import it into your web page. Instructions for perfoming a screen capture of an image.
5. Interpret a frequency distribution in terms of measures of central tendency, dispersion and general shape (modality, symmetry, etc)

Assignment_4 Pie Graph

Using Excel and some new data that you select, produce a pie graph. I suggest that you provide data which makes some point. Provide a paragraph which articulates how the graph demonstrates your case.

Goals:

1. Use spreadsheet to input data.
2. Produce a pie graph using the software. Use Titles, Labels and Legends where relevant.
3. Provide a link to the data, and identify the source.
4. Successfully capture the graph and put it on the web page.
5. Interpret the graph.

Assignment # 5 Bar Graph

Using Excel and the 'raw magnitude' data you obtrained inAssignment #1, produce a bar (or column) graph. I suggest that you provide data in order to make some point. Provide a paragraph which articulates how the graph demonstrates your case.

Goals:

1. Use spreadsheet to input data.
2. Produce a bar graph using the software. Use Titles, Labels and Legends where relevant.
3. Provide a link to the data, and identify the source.
4. Successfully capture the graph and put it on the web page.
5. Interpret the graph.

Assignment # 6 Line Graph - Time Series Plot

Using Excel and data tiome series data from Assignment #1, produce a line graph which shows data across time (Time series data is not strictly required for this assignment, however, it is usually what is needed for this type of graph to be preferable to a bar graph.). Provide a paragraph which articulates how the graph demonstrates your case.

Goals:

1. Use spreadsheet to input data.
2. Produce a time-series plot using the software. Use Titles, Labels and Legends where relevant.
3. Provide a link to the data, and identify the source.
4. Successfully capture the graph and put it on the web page.
5. Interpret the graph.

   
   

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Assignment # 7 Converting Nominal Dollars to Real Dollars (Controlling for Inflation)

Using Excel and the time series data used in Assignment #6 that involves money over time (e.g. per capita income for the period 1960-1995) convert the raw (nominal) dollar values into real dollars. See the handout for this assignment.

Goals:

1. Use spreadsheet to input data
2. Produce a time-series plot using the software. Use Titles, Labels and Legends where relevant.
3. Using the appropriate deflator, and merthod, adjust the nominal dollar data to real dollars.
4. Provide a link to the price deflator data, and identify the source.
5. Successfully capture the graph and put it on the web page.
6. Interpret the graph.

Assignment # 8 T-Test

Develop a hypothesis about whether some sample is different from some population? Collect data for which you have a population mean, and then define a sub sample from it. For instance, using one of your 50 state data sets, test whether a subsample is different from the population mean.

Goals:

1. Formulate a hypothesis about the difference between a population and a sample.
2. Specify the subset.
3. Perform the calculations in Excel.
4. Interpret a t-test output and write up a 1 page description of the results of the hypothesis test. See the example of the t-test.

Assignment # 9 Two-sample t-test

Develop a hypothesis about the difference between two groups. Collect the data and perform the appropriate comparison between them.
Goals:

1. Formulate a hypothesis about the difference between two sample means.
2. Specify the two subgroups.
3. Properly interpret the F-test for different sample variances.
4. Produce and capture the output using STATA
5. Interpret a t-test output and write up a 1 page description of the results of the hypothesis test. Include a table of yuour t-test results. See the example of the t-test.

   Demonstration of how to do this assignment.

For full Content points:

For full Presentation points:

Assignment #10 Regression, Correlation, & Multiple Regression

Using a data set which I will supply, test a number of interrelated hypotheses. (Use the presidential popularity data. ??)
Goals:

1. Formulate a set of hypothesis about the relationships between several independent variables and a dependent variable.
2. Test a bivariate hypothesis.
3. Examine a bivariate scatterplot.
4. Test a multiple regression model.
5. Produce and print output using STATA.
   Interpret the regression output for all analyses and write up a 1 page description of the results of the hypothesis tests. See the example of the regression analysis.

For full Content points:

For full Presentation points: