EDUR 8132
Educational Statistics 2
Spring 2016
Instructor: Bryan W. Griffin (bwgriffin@GeorgiaSouthern.edu)
My personal web pages:
http://www.bwgriffin.com
Course Index (e.g., tests, activities, reading and other material to review for each class session)
- Regression
- Regression: One Qualitative Predictor with Two Categories
- One Qualitative Predictor with Three or more Categories
- Multiple Qualitative Predictors
- Multiple Quantitative Predictors
- Both Qualitative and Quantitative Predictors
- ANOVA
- One-way ANOVA
- Two-way ANOVA without Interaction
- Two-way ANOVA with Interaction
- One-way ANCOVA
- Two-way ANCOVA
- One-way ANCOVA with Covariate by Factor Interaction
- Other Statistics
- Review of Basics
- Introductory notes -- to be discussed during initial chat; covers variables, IV vs. DV., modeling behavior, central tendency, variability, correlation, t-test, hypothesis testing logic.
- Hypotheses -- Watch video "Section 5: Hypotheses" below to ensure you understand how to write hypotheses. The supplemental notes referenced in the video are linked below and entitled "Supplemental Notes Displayed in Videos".
- Supplemental Review Material Taken from EDUR 8131 Educational Statistics 1
- Notes 1 Descriptive Statistics (content of videos below, taken from EDUR 8131 Educational Statistics 1)
- Displaying Data (frequency distributions, stem-and-leaf, bar charts, histograms, pie charts, box plots, scatterplots)
- Instructional Videos and Related Materials
- Supplemental Notes Displayed in Videos
- Supplemental Excel File Displayed in Videos
- Section 1: Descriptive vs. Inferential Statistics (also SPSS data entry explained)
- Section 2: Variables
- Section 3: Scales of Measurement
- Section 4: Types of Variables
- *Section 5: Hypotheses
- Sections 6, 7, and 8: Central Tendency (also SPSS showing descriptive statistics)
- Section 9: Distributions and Central Tendency
- Section 10: Mean of Groups
- Section 11: Inference and Sampling Error
- Sections 12 and 13: Measures of Variability (also SPSS examples)
- *Section 14: Frequency Distribution and Percentile Ranks (SPSS examples; Supplemental Notes for this video)
- *Section 15, 16, 17: Graphical Displays (SPSS examples)
- Supplemental Reading and Exercises:
- Variables and scales of measurement (variable/constant; scales; quan./qual.; IV/DV) (practice exercise)
- Hypotheses (directional/nondirectional/null; qual. vs. quan. wording; categories compared; writing; problematic-no difference between IV and DV, qual. IV affects DV [e.g., type of instruction affects DV]) (practice exercise #1, practice exercise #2)
- Notes 4 Hypothesis Testing and One Sample Z Test (logic of hypothesis testing, errors in hypothesis testing)
- Videos for Notes 4 Hypothesis Testing and One Sample Z Test
- Supplemental Excel File Shown in Videos
- Section 1: Logic of Hypothesis Testing with a Fair Coin
- Sections on One-sample Z test omitted
- Sections 4 and 5: Errors in Hypothesis Testing (and assumptions of Z Test)
- Section 6: Power
- Notes 5b Independent Samples t-test
- Critical t-values table: t-tables.pdf
- Instructional Videos and Related Materials
- Excel File: Two-group t-test and F-max Test
- Sections 1 and 2: Overview, Purpose, Steps in Hypothesis Testing
- Sections 3 and 4: Hypotheses and Decision Rules
- Section 5: t-test with Equal Variances -- Formula, Standard Error, and df
- Section 6: Finding Critical Values for t-test
- Section 7: Example 1 t-test with Equal Variances -- Formulas
- Section 7: Example 1 t-test with Equal Variances -- SPSS
- Section 7: Example 1 t-test with Equal Variances -- Excel
- Section 7: Example 2 t-test with Equal Variances -- Formulas and SPSS (SPSS starts at about 5:45 in video)
- Section 7: Example 2 t-test with Equal Variances -- Excel
- *Section 8: Heterogeneity of Variances
- Section 9: Assessing Homogeneity of Variance -- Levene's Test (SPSS)
- Section 9: Assessing Homogeneity of Variance -- F-max Test
- Section 9: Assessing Homogeneity of Variance -- F-max Test with Excel
- Section 10: t-test with Unequal Variances -- Formula, Standard Error, and df
- Section 11: Example 1 t-test with Unequal Variances -- SPSS and Excel
- Section 11: Example 2 t-test with Unequal Variances -- SPSS and Excel
- Section 12: Confidence Intervals - Example 1 (SPSS)
- Section 12: Confidence Intervals - Example 2 (SPSS)
- *Section 13: Equal vs. Unequal t-test - Comparison of Results
- Section 14: APA Style Presentation - t-test with Equal Variances
- Section 14: APA Style Presentation - t-test with Unequal Variances
- Section 14: APA Style Presentation - Multiple t-tests with same Group and Text Format
- Notes 6 Correlation
- Critical Pearson r values table: critical r
- Critical t-values table: t-tables.pdf
- Video - Correlation and Causation: English is the Cause of Death (4 minutes)
- Instructional Videos and Related Materials
- *Section 1: Correlation
- *Section 2: Properties of Pearson's r (used SPSS to create scatter plots)
- *Section 3: Factors that May Alter Pearson's r
- *Sections 4 and 5: Correlation and Causation, Pearson r Calculation (use of SPSS to calculate Pearson r starts 4:18 in video)
- Section 6: Hypothesis Testing with t-ratios (Section 6, subsections a through e)
- Section 6: Hypothesis Testing with Critical r values (Section 6, subsection f)
- Section 6: Hypothesis Testing with p-values (Section 6, subsection g)
- SPSS data files used in subsection g (note that data are fictitious):
- Hours Studied and Statistic Grades
- Academic Self-efficacy and Test Anxiety
- Section 6: Hypothesis Testing Exercise (Section 6, subsection h)
- *Section 7: Correlation Matrices
- Section 8: APA Style Presentation
- Section 9: r2 - proportional reduction in error
- Section 10: Alternative Correlations (to be added)
- Excel file showing Z score formula for finding a correlation: Z score formula for finding correlation
- Supplemental Readings:
- Read this: Correlation Coefficients and Scatterplots
- http://www.wadsworth.com/psychology_d/special_features/ext/workshops/correlation.html
- http://www2.chass.ncsu.edu/garson/pa765/correl.htm
- http://davidmlane.com/hyperstat/A34739.html
- http://www.wellesley.edu/Psychology/Psych205/pearson.html
- http://www.une.edu.au/WebStat/unit_materials/c6_common_statistical_tests/test_signif_pearson.html
- Simple Regression with One Quantitative Predictor
- Notes 8a Simple Regression
- Critical F Ratio Table: Critical F-ratio
- Critical t values Table:: Critical t
- Instructional Videos and Related Materials
- Supplemental notes shown in video: Supplemental Notes 8a
- *Sections 1 and 2: Regression Model and Figure 1
- *Section 2: Figure 2
- *Section 2: Figure 3
- *Section 3: Least Squares and Residuals
- *Section 4: Literal Interpretation of Coefficients
- *Section 4: Example 1 Barometric Pressure and Water Boiling Point
- Data File in SPSS Format: Barometric Pressure and Boiling Point of Water
- Section 4: Example 2 Irrigation and Cotton Yield
- Data File in SPSS Format: Irrigation and Cotton Yield
- Section 4: Example 3 Car Weight and Mile Per Gallon (MPG)
- Data File in SPSS Format: Car Weight and MPG
- Section 5: Model Fit
- Section 6: Inference in Regression - Overall Model Fit (Part 1, Overall Model Fit on page 10 through Calculated and Critical F Ratio on page 11)
- Section 6: Inference in Regression - Overall Model Fit (Part 2, starts with Exercises on page 11 and ends at Coefficient Inference on page 12)
- Section 6: Inference in Regression - Coefficient Inference
- Section 6: Inference in Regression - Confidence Intervals for Coefficients
- Section 7: APA Style for Student Grades and Instructional Ratings
- To be revised -- Detailed notes: Notes 8a Regression with One Quantitative Predictor
- Differences between Summary notes above and these Detailed notes will be highlighted soon
- Model Fit: R2, SEE and MSE, and Adjusted R2
- Multiple Regression with Multiple Quantitative Predictors
- Notes 8b Multiple Regression
- Regression Coefficient Interpretation
- Critical F Ratio Table: Critical F-ratio
- Videos and Related Material for Summary Notes 8b:
- 01 Purpose, Equation, and Partial Effects
- 02 Partial Effects
- 03 Partial Effects Part 2
- 04 Residuals and Literal Interpretation
- 05 Ice Cream Example
- 06 House Price Example
- 07 Model Fit
- 08 Inference
- 09 Confidence Intervals (Short video showing Confidence Interval with SPSS with difference confidence levels)
- 10 APA Styled Results (Word document of House Price Example in APA Style )
- To be revised -- Detailed notes: Notes 8b Regression with Two Quantitative Predictors (Minor update to Notes 8b: the value of ΔR2 is actually the squared semi-partial correlation)
- Differences between Summary notes above and these Detailed notes will be highlighted soon
- Reading Published Research Results:
- Squared Semi-partial Correlation (ΔR2)
- Notes 8c Regression Squared Semi-partial Correlation
- Detailed notes: Read Notes 8b page 5 section entitled "ΔR2, Semi-partial Correlation, and the Partial F Test of ΔR2"
- Video: ΔR2 Discussed and Illustrated in SPSS; ΔR2 Notes used in video; Test Score Data (in SPSS format) used in video
- (Note: SPSS syntax offers easy way to obtain several ΔR2 values and F ratios simultaneously: change Method=enter x1 x2 x3 x4 to Method=test (x1) (x2 x3) (x4). For Video data above, this command change produces summary output: "/METHOD=ENTER Study_Time IQ Griffin Moore" to this "/METHOD=TEST (Study_Time) (IQ) (Griffin Moore)" Add video segment to video above demonstrating this.
- Table of Critical F-ratios: Critical F at .05 and .01
- Instructor's note: Review all notes and change label from "semi-partial correlation" to "squared semi-partial correlation"
- Regression with One Qualitative Predictor
- Summary notes for on-line chat: One qualitative dichotomous predictor (2 categories)
- Summary notes for on-line chat: (to be added One qualitative predictors with 3+ categories
- Detailed notes: Notes 8d Regression with One Qualitative Predictor
- Detailed notes: Notes 8e Regression Multiple Comparisons
- Table of Bonferroni Critical t-ratios: Dunn's Critical Values for Bonferroni t
- Excel file for Bonferroni and Scheffe Confidence Intervals
- SPSS Data: Cars with Origin Dummies and Missing Data Removed
- Creating Dummy Variables in SPSS using the Computer and Recode Commands
- Regression with Multiple Qualitative and Quantitative Predictors
- Summary notes for chat: Notes 8f Regression with Two Qualitative Predictors Summary
- Summary notes for chat: Notes 8g Regression with Both Qualitative and Quantitative Predictors Summary
- Detailed notes: Notes 8f Regression with Two Qualitative Predictors
- Detailed notes: Notes 8g Regression with Both Qualitative and Quantitative Predictors
- Excel file for Bonferroni and Scheffe Confidence Intervals
- SPSS Data: Cars with Origin Dummies and Missing Data Removed
- Effect sizes in regression (to be added)
- Sample size for regression (to be added)
- Standardized Regression Equation
- Notes 8h Regression Standardized Coefficients (Note to instructor - update formatting, also check standardized equation subscripts)
- One-way ANOVA Models (Note to instructor -- briefly discuss finding and using critical F values)
- Notes 9 ANOVA
- Homework answers to problems found in Notes 9 ANOVA
- Some ANOVA Exercises with APA answers (note table missing R2 values, these should be added)
- Critical F Ratio Table: Critical F-ratio
- Instructional Videos and Related Materials
- Supplemental Excel File used in videos: Notes 9 Video Excel File
- Sections 1 and 2: Purpose and Hypotheses
- Section 3: Inflation of Type 1 Error
- Section 4: Linear Representation of ANOVA Model
- Section 5a: ANOVA Computation -- Logic of F-ratio
- Section 5a: ANOVA Computation -- Graphical Illustration of F-ratio
- Partition of Variation Illustration 1: Google Docs Distributions
- Partition of Variation Illustration 2: F-ratio with Sample Data (Rossman/Chance Applet)
- Partition of Variation Illustration 3: F-ratio with Sample Data (Monash University; excellent demonstration when functioning)
- Partition of Variation Illustration 4: F-ratio with Sample Data (WH Freeman and sumanasinc.com )
- Section 5b: ANOVA Computation -- Sums of Squares Total and Between
- Section 5b: ANOVA Computation -- Sums of Squares Within
- Section 5c: ANOVA Computation -- degrees of freedom
- Section 5d and 5e: ANOVA Computation -- Estimating Variance; F-ratio and Critical F
- Section 6: SPSS both One-way ANOVA and General Linear Model Univariate Commands Illustrated
- Section X: Equivalence Among ANOVA, Regression, Correlation, and Independent Samples t-test
- Section 7: Multiple Comparisons (VIDEO AND NOTES TO BE ADDED)
- Section 8: SPSS Multiple Comparisons
- Section 9: APA Style Presentation of ANOVA Results (TO BE ADDED)
- Multiple Comparisons for Regression Coefficients (TO BE ADDED)
- Excel Spreadsheet: Bonferroni and Scheffe
- Online with EditGrid: Bonferroni and Scheffe
- Online with Zoho: Bonferroni and Scheffe (this spreadsheet does not work correctly)
- Multi-way ANOVA Models
- Notes 9b ANOVA without Interactions
- Notes 9c ANOVA with Interactions (Video: ANOVA with Interactions in SPSS)
- Notes 9d ANCOVA
- Supplemental Reading: Stevens Chapter 7 ANCOVA
- Excel Spreadsheet for Interactions
- Video: One-way ANCOVA with three groups
- Video: Two-way ANCOVA
- Video: One-way ANCOVA with Factor*Covariate Interaction (Unfortunately sound spikes and breaks occasionally)
- EdS Read Aloud, Think Aloud Data Results (Chat 15 worked example of ANCOVA with interaction)
- ANCOVA Data Examples
- Sample Data 1: Fictional salary discrimination
- Sample Data 2: Gun control and homicides by state
- Sample Data 3: Fictional achievement data - homework with parental support
- Sample Data 4: FFictional data showing ANCOVA power vs ANOVA
- Sample Data 5: Car MPG by country of origin controlling for horsepower and weight
- Add Waldron data to illustrate difference between gain score and ANCOVA
- Spreadsheet to Calculate Bonferroni and Scheffé Confidence Intervals (based on Editgrid.com)
- Same as above, except in Excel format
- Multiple Comparisons in Excel: Bonferroni and Scheffe (speadsheet may provide incorrect CIs)
- Multiple Comparisons in Zoho (on-line spreadsheet): Bonferroni and Scheffe (speadsheet may provide incorrect CIs)
- Possible Additional Content
- Effect sizes in ANOVA
- Sample size for ANOVA
- Interactions in Regression
- Polynomial Regression
- Model fitting and assessment (multicollinearity, nonlinearity, etc.)
- Common Research Designs and Related Statistical Analysis (e.g. Post-test only control, Pretest-posttest control, Non-equivalent control group, etc.)
- Logistic regression or Factor Analysis
Topic |
Readings |
1. Hypothesis Testing Logic | Chapters 5, 6 |
2. Regression | Chapter 9 |
3. Multiple Regression | Chapters 10, 11 |
4. ANOVA | Chapter 12 |
5. ANCOVA/Regression | Chapter 13 |
6. Modeling building in Regression/ANOVA | Chapter 14 |
7. Logistic Regression | Chapter 16 |
Course Calendar (will be revised throughout term)
Week 1 (1/11)
- Syllabus
- Introductory Notes (variables, IV vs. DV, modeling behavior, central tendency, variability, correlation, t-test, SPSS, hypothesis testing logic)
- Instructor's note - live chats covered through correlation
Self -Assessment Activity
Review of Basics - Writing Hypotheses, Descriptive Statistics t-test, Pearson r, Hypothesis Testing
Question 5 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week01/Week01Q5Data.sav
Excel: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week01/Week01Q5Data.xlsxReview of Basics - Answers
Videos of Answers
Question 3 (Time = 2:20): SPSS Frequencies and descriptive statistics
Question 4 (Time = 4:20): SPSS Independent samples t-test
Question 5 (Time = 4:45): SPSS Pearson Correlation
Week 2 (1/18)
- Complete Introductory Notes (as needed)
- Simple Regression: Notes 8a (with one quantitative predictor)
- Instructor's note - live chats covered through student ratings example, resume at Additional Examples
Self -Assessment Activity Regression - with One Quantitative Predictor
Question 2 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week01/Week01Q5Data.sav
Excel: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week01/Week01Q5Data.xlsxRegression Answers - to self-assessment linked above
Videos of Answers (to be added)
Question 2 (Time = ):
Week 3 (1/25)
- Resume "Simple Regression: Notes 8a" as needed
- Model Fit
Activity for Weeks 2 and 3 are combined, so see activity in Week 2.
Week 4 (2/1)
- Multiple Regression: Notes 8b (two or more quantitative predictors)
- Instructor's note - covered 8b, but not APA presentation of final example
Self -Assessment Activity
Multiple Regression -- examining the partial contribution of several predictorsQuestions 2 and 3 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week04/cars_missing_deleted.sav
Multiple Regression Answers
Other: Let me know if you prefer a different data file format other than SPSS
Week 5 (2/8)
- Continue with "Multiple Regression: Notes 8b"
- Regression Squared Semi-partial Correlation (ΔR2) Notes 8c
Activity for Weeks 4 and 5 are combined, so see activity in Week 4.
Test 1 posted after Multiple Regression and Model Fit covered, approximately 2/8 or 2/15
Week 6 (2/15)
- Regression with One Qualitative Predictor: Notes 8d
Self -Assessment Activity
Regression with a Qualitative Predictor -- group comparisons with regressionQuestion 5 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week04/cars_missing_deleted.sav
Regression with a Qualitative Predictor Answers
Other: Let me know if you prefer a different data file format other than SPSS
Week 7 (2/22)
- Resume Notes 8d
- Regression Multiple Comparisons: Notes 8e
- Possibly begin Regression with Two Qualitative Predictors: Notes 8f
- Instructor's note - covered 8d
Activity for Weeks 6 and 7 are combined, so see activity in Week 6.
Week 8 (2/29)
- Regression with Two Qualitative Predictors: Notes 8f
- Instructor's note - completed qual. predictor, briefly discussed interpretation with two qual IVs, began multiple comparisons
Self -Assessment Activity
Regression and Multiple Comparisons with Several Qualitative Predictors -- group comparisons with regressionQuestion 4 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week04/cars_missing_deleted.sav
Answers for Regression and Multiple Comparisons with Several Qualitative Predictors
Other: Let me know if you prefer a different data file format other than SPSS
Week 9 (3/7) (Instructor's Note: Fall 2010 covered notes on multiple comparisons)
- Regression with Both Qualitative and Quantitative Predictors: Notes 8g
- Instructor's note - covered MCs
Self -Assessment Activity
Regression with both Qualitative and Quantitative Predictors (and Multiple Comparisons)Question 2 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week09/BloodPressureDrugs.sav
Excel: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week09/BloodPressureDrugs.xlsxQuestion 3 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week04/cars_missing_deleted.sav
Answers for Regression with both Qualitative and Quantitative Predictors (and Multiple Comparisons)
Other: Let me know if you prefer a different data file format other than SPSS
Spring Break - March 14 to 18
Week 10 (3/21)
- Notes 8h: Standardized Regression Equation? (present this during week 14?)
- Effect sizes?
- Sample sizes?
- Instructor's Note - covered notes on multiple comparisons with two qual IVs.
Test 2 posted once regression completed, approximately 3/21
Week 11 (3/28)
- ANOVA: Notes 9 and 9b.
Self -Assessment Activity
ANOVA and Regression: A ComparisonQuestion 1 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week09/BloodPressureDrugs.sav
Excel: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week09/BloodPressureDrugs.xlsxQuestion 3 Data
SPSS: http://www.bwgriffin.com/gsu/courses/edur8132/selfassessments/Week04/cars_missing_deleted.sav
Answers for ANOVA and Regression: A Comparison (at this point only software results are presented; written answers still to be provided)
Other: Let me know if you prefer a different data file format other than SPSS
Week 12 (4/4)
- ANOVA: Notes 9 and 9b
- Notes 9c
Week 13 (4/11)
- Notes 9c
- Notes 9d: ANCOVA
Week 14 (4/18)
- Notes 9d
- Standardized regression coefficients
- Read Agresti text on standardized regression coefficients pages 270, 351-354, 529-532. Also, see my discussion in Notes 8a Regression with One Quantitative Predictor (see page 10) and Notes 8b Regression with Two Quantitative Predictors (also starting on page 10).
No Class 11/26 Thanksgiving
Week 15 (4/25)
Test 3 posted sometime around 4/26
Test 3 due 5/3
NOTE -- Ignore Material below this point
Course Assessment Questionnaire
General Readings on ANOVA:
ANCOVA
Instructor's Note: add links to on-line statistical programs, e.g.
http://home.ubalt.edu/ntsbarsh/Business-stat/otherapplets/SampleSize.htm#rmenu
http://noppa5.pc.helsinki.fi/koe/flash/flash.html
Copyright 2005, Bryan W. Griffin
Last revised on 05 January, 2024 08:03 AM