Applied Statistics (M358K)

Extra credit #1 - this is the Rmd file which you are more than welcome to use to neatly complete your quiz; you will not be able to knit this file as is unless you comment out or delete the R-chunk which inserts the picture

Data: Simplified Titanic data - courtesy of the Journal of Statistics Education

R notebook titanic.Rmd

R notebook titanic-in-class.Rmd as amended in class

xkcd

Florence Nightingale

Wikipedia: Mean household income

Graph: US Household Income Distribution

Here is a list of fun sites which make charts: Infogram, FastCharts, Flourish, Datawrapper

Class 8: September 8th
Median. Quartiles. (Sections 2.1.5, 2.1.6, 2.1.1)

Slides - Courtesy of Open Course Statistics

R script invented-data.R from class

Return values from boxplot

ProPublica: New Climate Maps Show a Transformed United States

Data: Student-run cafe - courtesy of the Journal of Statistics Education

Homework #4 – due on Friday, September 22nd, 2023

Homework #4 - this is the Rmd file which you are more than welcome to use to neatly complete your homework; you will not be able to knit this file as is unless you comment out or delete the R-chunk which inserts the picture

Class 9: September 11th
Scatterplots (Section 1.2.3).

Data: Carats vs. dollars - courtesy of the Journal of Statistics Education

R-script diamond-scatterplot.R

On plotting scatterplots in R - this is a demo in R by yours truly on how to draw scatterplots; feel free to start at 2:35 and watch at twice the speed

Adding legends to your R plots

Duke gpa - courtesy of OpenCourse Statistics

The R-notebook for class

The R-notebook from class - I added a few features to our work in class, so check it out

Gapminder: How Does Income Relate to Life Expectancy?

Homework #5 – due on Friday, September 29th, 2023

Class 10: September 13th
Sampling principles and strategies (Section 1.3)

Slides - Courtesy of Open Course Statistics

Problem Set #1 - problems

Problem Set #1 - solutions

In-Term One Topics

Practice for In-Term One - Problems

Practice for In-Term One - Solutions

Class 11: September 15th
Randomized response.

James Grime on randomized response

Wikipedia: Randomized response

Problem Set #2 - problems

Problem Set #2 - solutions

Class notes

Class 12: September 18th
Experiments (Section 1.4)

Open Course Video

Slides - Courtesy of Open Course Statistics

Problem Set #3 - problems

Problem Set #3 - solutions

Class Notes

A historical example

Suggested textbook problems (for after you are done with all the homework): 1.19, 1.20, 1.23, 1.26, 1.27, 1.28, 2.11, 2.13, 3.9, 3.10, 3.13, 3.19

Project #3 – due on Monday, October 9th

Project #3 - this is the Rmd file which you are more than welcome to use to neatly complete your quiz

Follow up on the “Experiment experiment”

Andrew Gelman on the “replication crisis”

Class 13: September 20th
In-Term One

In-Term One - solutions

Class 14: September 22nd
Review of continuous distributions.

Class notes

Extra-Credit Quiz #3 – due on Wednesday, October 4th

Extra-Credit Quiz #3 - this is the Rmd file which you are more than welcome to use to neatly complete your quiz

Class 15: September 25th
Statistical inference. Statistics and the sampling distribution.

R notebook Odin.Rmd

Sample versus Theoretical Distribution from the Wolfram Demonstrations Project by Joe Bolte

Point estimates and sampling variability (Section 5.1)

Slides - Courtesy of Open Course Statistics

R notebook prop.Rmd

Problem Set #4 - problems

Problem Set #4 - solutions

Class 16: September 27th
The normal distribution [review] (Section 4.1, Appendix C.1)

Class notes

The R-script from class

Standard Normal Distribution Areas from the Wolfram Demonstrations Project by Ian McLeod

The Normal Distribution from the Wolfram Demonstrations Project by Ian McLeod

Area of a Normal Distribution from the Wolfram Demonstrations Project by Eric Schulz

Standard normal table

Slides - Courtesy of Open Course Statistics

Wikipedia: Six sigma

How to shade in R

Homework #6 – due on Friday, October 6th

Homework #6 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

Mystery Data: this data set is necessary for Project #4

Bitcoin Data: this data set is necessary for Project #4

Project #4 – due on Monday, October 23rd

Project #4 - this is the Rmd file which you are more than welcome to use to neatly complete your project

%in% in R

Class 17: September 29th
More on the normal distribution.

Problem Set #5 – problems

Problem Set #5 – solutions

Class notes

Class 18: October 2nd
The normal approximation to the binomial [review] (Sections 4.3.2 and 4.3.3).

Problem Set #6 – problems

Class notes

The R-script from class

Problem Set #6 – solutions

Mathematica demonstration: The Normal Approximation to the Binomial Distribution

Open Course Video: Normal approximation to the binomial

Class 19: October 4th
The Central Limit Theorem [review] (Sections 5.1.3 and 7.1.1).

Problem Set #7 – problems

Class notes

Wikipedia: On the gamma distribution

The R-script from class

Problem Set #7 – solutions

Homework #7 – due on Friday, October 13th, 2023

Homework #7 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

Class 20: October 6th
Sample mean (the normal case).

Lecture notes: The normal sample mean

Problem Set #8 – problems

Class notes

Problem Set #8 – solutions

Quiz #7 – due on Friday, October 8th

Quiz #7 - this is the Rmd file which you are more than welcome to use to neatly complete your quiz

Class 21: October 9th
Confidence intervals (the normal case).

Class notes

Class 22: October 11th
More on confidence intervals (the normal case).

R notebook normal-conf-int.Rmd

Shiny: Confidence intervals

Problem Set #9 – problems

Problem Set #9 – solutions

Extra credit #4 – due on Wednesday, October 25th

Homework #8 – due on Friday, October 20th, 2023

Homework #8 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

In-Term Two Topics

Practice for In-Term Two - Problems

Practice for In-Term Two - Solutions

Principles of hypothesis testing.

Class notes

Class 23: October 13th
The \(p−\)value. More on hypothesis testing in the normal case.

Class notes

Problem Set #10 – problems

Problem Set #10 – solutions

Extra-Credit Quiz #5 – due on Wednesday, November 1st, 2023

Extra-Credit Quiz #6 – due on Wednesday, November 8th, 2023

Class 24: October 16th
The reasoning of tests of significance. Inference as a decision.

Problem Set #11 – problems

Class notes

Problem Set #11 – solutions

\(p-\)hacking is bad

Class 25: October 18th
In-Term Two

In-Term Two - Solutions

Class 26: October 20th
Hypothesis-testing practice (the normal case).

Problem Set #12 – problems

Class notes

An article on p-hacking in biology

A blog post on p-hacking with an interactive component (pardon the expletives!)

Problem Set #12 – solutions

Class 27: October 23rd
Types of errors.

Errors

Class notes

Problem Set #13 – problems

Problem Set #13 – solutions

R-bloggers: QQ-plots in R

Data: this data set is necessary for Project #5

Project #5 – due on Monday, November 13th

Project #5 - this is the Rmd file which you are more than welcome to use to neatly complete your project

Class 28: October 25th
Power of test (the normal case).

Power of test

Problem Set #14 – problems

Class notes

Homework #9 – due on Friday, November 3rd

Homework #9 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

Problem Set #14 – solutions

Class 29: October 27th
The sampling distribution for counts and proportions. Confidence intervals (Sections 6.1.1, 6.1.2, and 6.1.5)

Open course video: Statistical inference for proportions.

Class notes

Problem Set #15 – problems

Problem Set #15 – solutions

Quiz #11 – due on Friday, November 5th, 2021

Homework #10 – due on Friday, November 10th

Homework #10 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

Class 30: October 30th
Hypothesis testing for a proportion (Section 6.1.3)

Class notes

Problem set #16 – problems

Problem set #16 – solutions

Class 31: November 1st
Comparing two proportions (Sections 6.2.1, 6.2.2, 6.2.3, 6.2.5)

Complete class notes

Problem set #17 – problems

Problem set #17 – solutions

Quiz #12 – due on Friday, November 12th, 2020

Homework #11 – due on Friday, November 17th

Homework #11 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

Class 32: November 3rd
The \(\chi^2-\) distribution (Sections 6.3.3, C.3)

Zed Statistics video: The \(\chi^2-\) distribution.

Class notes

\(\chi^2-\)table

A better \(\chi^2-\)table

Mathematica demonstration: The Chi-Squared Distribution

Mathematica demonstration: Tail Areas under the Chi-Squared Distribution

Class 33: November 6th
Goodness of fit (Sections 6.3.1, 6.3.2, 6.3.4)

Open course video: Goodness of fit.

Class notes

Problem set #18 – problems

Problem set #18 – solutions

Class 34: November 8th
Analysis of two-way tables.

James Grime on the Simpson’s paradox

Chi-squared test of independence (Section 6.4)

Class notes

Slides - Courtesy of Open Course Statistics

R-code: On-line courses or not?: An example on how to do the \(\chi^2-\)test of independence in R

Quiz #13 – due on Friday, November 19th, 2021

Class 36: November 10th
\(\chi^2-\)connections to normal samples.

Statistics Associated with Normal Samples from the Wolfram Demonstrations Project by Pierre-Emmanuel Robert

Quiz #14 – due on Friday, December 3rd, 2021

The \(t-\)distribution (Sections 7.1.3 and C.2).

Wikipedia: William Sealy Gosset

Mathematica demonstration: The Student’s t-distribution

t-table

Class notes

Data: this data set is necessary for Project #6

Project #6 – due on Monday, December 4th

Project #6 - this is the Rmd file which you are more than welcome to use to neatly complete your project

Wikipedia: Fisher’s exact test

Class 36: November 13th
The confidence interval for the population mean (Section 7.1.1, 7.1.2, 7.1.4)

Class notes

R-code: Normality check for Dobson

R-code: Confidence intervals with t.test

Class 37: November 15th
The t-test (Section 7.1.5)

Class notes

Slides - Courtesy of Open Course Statistics

In-Term Three Topics

Practice for In-Term Three - problems

Practice for In-Term Three - solutions

Class 38: November 17th
t-procedures practice.

Problem set #19 – problems

Class notes

Problem set #19 – solutions

Robustness of t-procedures (optional).

Robustness of Student t in the One-Sample Problem from the Wolfram Demonstrations Project by Ian McLeod

The Royal Society of Chemistry on robustness

Paired data (Section 7.2)

Slides - Courtesy of Open Course Statistics

Homework #12 – due on Friday, December 1st

Homework #12 - this is the Rmd file which you are more than welcome to use to neatly complete your homework assignment

The Final Project – due on the date of your final exam

Class 39: November 27th
Difference of two means (Section 7.3)

Class notes

Slides - Courtesy of Open Course Statistics

Quiz #15 – due on Monday, December 6th for extra credit

t-procedures [practice].

The R-script from class

Problem set #20 – problems

Problem set #20 – solutions

Class notes

Mock In-Term Three - Problems

Mock In-Term Three - Solutions

Class 40: November 29th
In-Term Three

In-Term Three - solutions

Class 41: December 1st
Correlation. Causation (Section 8.1.4)

xkcd: Correlation

Class notes

Visualizing Correlations from the Wolfram Demonstrations Project by Ian McLeod

Anscombe Quartet from the Wolfram Demonstrations Project by Ian McLeod

Datasaurus

Problem set #21 – problems

Problem set #21 – solutions

Data: Shoe size and height - courtesy of the Open Course Statistics: this data set is necessary for Quiz #16

Quiz #14 – solutions

Quiz #16 – due on Monday, December 6th for extra credit

Quiz #16 - this is the Rmd file which you are more than welcome to use to neatly complete your quiz

Class 42: December 4th
Fitting a line. Residuals (Sections 8.1.1, 8.1.2, 8.1.3)

Slides - Courtesy of Open Course Statistics

Class notes

Least-squares. Predictive statistical tools (Section 8.2)

Least squares with the mechanical analogue

Simple linear regression.

Least Squares Criteria for the Least Squares Regression Line from the Wolfram Demonstrations Project by Mariel Maughan

Mean, Fitted-Value, Error, and Residual in Simple Linear Regression from the Wolfram Demonstrations Project by Ian McLeod

R-code: Simple linear regression

Regression toward the Mean from the Wolfram Demonstrations Project by Ian McLeod

Quiz #17 – due on Monday, December 6th for extra credit

Simple linear regression [cont’d].

R-code: Confidence intervals

The Final Exam Topics

The Final Exam Practice – problems

The Final Exam Practice – solutions

Three interesting special topics

Lady tasting tea.

Wikipedia: Lady tasting tea

R. Fisher: Mathematics of a Lady Tasting Tea

Lady Tasting Coffee: A case study in experimental design

The foster-twins study.

Wikipedia: Cyril Burt

The German tank problem.

Wikipedia: The German tank problem