**STAT 2023 Classes Spring 2020**

**20200430 Lesson 18**

Read and Study Lesson 18. Study the detailed example that follows Lesson 18.

Go to JBStatistics.com and watch videos 12.5, 12.6, 12.7, and 12.8.

**20200428 Lesson 18**

Read and Study Lesson 18. Study the detailed example that follows Lesson 18.

Go to JBStatistics.com and watch videos 12.1, 12.2, 12.3, and 12.4.

**20200421 and 20200423 Lesson 17**

Read and study Lesson 17. Here are some Lesson 17 Summary Notes.

When the parameter the difference between two population means is considered there are three cases:

1. When the population variances are known. Here is an example, Lesson 17 example population variances known

2. When the population variances are unknown, but assumed to be equal. Here is an example, which is an exercise on page 21 of Lesson 17, Lesson 17 example page 21 population variances unknown assume equality

3. When the population variances are unknown, but no assumption of equality is made. Here is an example, which is an exercise on page 27 of Lesson 17, Lesson 17 example page 27 population variances unknown no assumption of equality.

Some videos on JBStatitics.com to watch that cover Lesson 17 are 7.1, 7.2, 7.3, and 7.4.

**20200414 Review Day**

Work a past exam three of your choice and dropbox your work by 10pm Wednesday, April 15.

If you want a Word Doc so that you may type in the document here are some past exams in that format.

**20200409 Lesson 16 **

Read and study Lesson 16.

Go to https://www.jbstatistics.com/ and view the following videos:

6.1, 8.1, 8.2, 8.3, and 8.4.

**20200407 Lesson 15**

This video, https://youtu.be/gYdwHPw0ZpY, is a discussion of Lesson 15 Exercise 3.

Exercise 3 considers t-test for one-sample from Excel Output.

View the Syllabus link on the right side of main page. A revised syllabus is posted.

**20200402 Lesson 15**

This video, https://youtu.be/gOlGqXxwGBw, is a discussion of Lesson 15.

This video, https://www.youtube.com/watch?v=6z-hRNTVv-w, is a discussion of Lesson 15 Exercise 2.

Go to https://www.jbstatistics.com/ and view the following videos:

5.7, 6.9, 6.10, 6.18, and 6.19

**20200331 Lesson 15**

Read and Study Lesson 15 (Under Lessons for Exam Three right side links.) Notice there are examples for Lessons 13, 14, and 15 following Lesson 15.

Read and Study the class notes in the top center post. They compare the Z and t distributions.

Go to https://www.jbstatistics.com/ and view the following videos:

5.8, 6.8, 6.14, 6.15, and 6.16.

Here are two interesting articles about William S. Gosset, who developed the Student’s t-distribution:

Guinness Brewer Who Revolutionized Statistics

**20200326 Lesson 14**

Watch and study these videos.

This video, https://youtu.be/FD9pEWHgpto, is a discussion of Lesson 14.

This video, https://youtu.be/JYk5Pp9AEgI, is a discussion of Lesson 14 Exercise 1.

This video, https://youtu.be/vZt-nfRUnXM, is a discussion of Lesson 14 Exercise 2.

**20200324 Lesson 14**

Read and Study Lesson 14 (Under Lessons for Exam Three right side links.)

Read and Study these class notes, Hyp Test Mean, Var Known, oil well 3 cases ND

**Watch these two videos** that are a review of what we did before break,

https://www.jbstatistics.com/intro-to-confidence-intervals-for-one-mean-sigma-known/

https://www.jbstatistics.com/confidence-intervals-for-one-mean-interpreting-the-interval/

**Hypothesis Testing** as described in Lesson 14 is covered by these videos. *Please Watch Them! *

https://www.jbstatistics.com/z-tests-for-one-mean-introduction/

https://www.jbstatistics.com/z-tests-for-one-mean/

https://www.jbstatistics.com/z-tests-for-one-mean-the-p-value/

https://www.jbstatistics.com/what-is-a-p-value/