Sunday, April 26, 2020

A Very Detailed Final Exam Check List. Posted Sunday April 26, 2020

Quick References for Final Exam.

Problem 1

1. JB with a two tailed hypothesis test.  He discusses outliers a bit for extra discussion.
    https://youtu.be/q1D4Di1KWLc

2. Problem 2 on this worksheet is an example of a 95% CI on one population mean. It is based on            problem10.5 in the textbook.
    https://drive.google.com/file/d/0B0G6ga3ykYRHeXcxNjdkNmRlYWc/view

3. There is an example on pages 393-395 worked out in the textbook.
---------------------------------------------------------------------------------------------------------------------
Problems 2 and 6.  Both are one way analysis of variance (a.k.a AOV or Anova) problems with the AOV table given along with the sample means for each group.
 A link to our textbook reference for chapter 11
link: https://drive.google.com/file/d/19Td_GXTWTIi_G9IL-Uj_qcXyP_4Be2IL/view

First some quick intro video:
Introduction to the AOV Procedure

a.  Introduction to One Way Analysis of Variance (ANOVA)
link: https://youtu.be/QUQ6YppWCeg

b. ANOVA. An Intro to Formulas
link: https://youtu.be/fFnOD7KBSbw

c.  A Numerical Example of a One Way ANOVA
link: https://youtu.be/WUoVftXvjiQ

d. Comparing Among k Means in ANOVA when F - Test is Significant.  First Basic Procedure.
link: https://youtu.be/kO8t_q-AXHE

e. A quick intro to Tukeys multiple comparison procedure.  A common approach more popular than LSD procedure discussed in d. above. The Tukey procedure will not be on the exam Spring 2020.
link: https://youtu.be/lpdFr5SZR0Q

f. Finding the Approximate P-Value from F - test Using Textbook F - tables
link: https://youtu.be/XdZ7BRqznSA
g.  AOV worksheet 
 link
h.  AOV Worksheet Answers (Sorry its a home scan :-) )
link:

i. Book Exercises for One Way Anova. Three problems are listed but pay particular attention to 11.12. It is very similar to exam questions 2 and 6.   Problems 11.12 (a,b,c) , 11.13 (b,d) , 11.14 (a,b)
link: https://drive.google.com/file/d/1Zcr5ZO77L_AVu5Sv1kX65iU5XRZC_fle/view?usp=sharing

a. Eric's handwritten solutions to the textbook problems 11.12 (a,b,c) , 11.13 (b,d) , 11.14 (a,b) 
  link: https://drive.google.com/file/d/0B0G6ga3ykYRHUnRfYUxjaHMtVzQ/view
------------------------------------------------------------------------------------------------------------
Problem 3.
Chapter 12 Topics.  Simple Linear Regression

Chapter 12 Textbook Reference from our B1 Text
link: https://drive.google.com/file/d/1pXBOqJPuLJG-BKSe3hPsbK1ne62suJ3T/view?usp=sharing

a. Intro to Linear Regression and Correlation Coefficient (r).
OpenStax Version
(A short 4 min video, at minute 3 a quick intro to 
Pearson's Correlation Coefficient is presented)
link: https://youtu.be/mPvtZhdPBhQ

b. Inference About the Slope b1, and Understanding Regression Output
from Software. OpenStax Version
link: https://youtu.be/depiT-hTaGA

c. Examples of Outliers in Regression. Discussion of 'Leverage' and 'Influence'
in a Regression Analysis.
link: https://youtu.be/jZEKAlo1E54

d. Interpretation of B0, B1, assumptions for linear regression, and R-Squared.
link: https://youtu.be/z8DmwG2G4Qc

e. Introduction to Linear Regression Marin Stats Version.
link: https://youtu.be/vblX9JVpHE8

f. Intro to Linear Regression JB Stats Version
link: https://youtu.be/KsVBBJRb9TE

g. Discussion of Linear Regression that Puts Several Concepts Together
JB Stats Version
link: https://youtu.be/xIDjj6ZyFuw

Practice Problems and Materials.

 Potency and Temperature Worksheet:

Notice we run this analysis for the worksheet in both R and SAS.  Notice how to find the important information in both of these common statistics software packages.  This worksheet is very similar to the exam question 3.

h.The R Software Printout.
link: https://drive.google.com/file/d/0B0G6ga3ykYRHWnNwVnllTlhwcHc/view

i. The worksheet (last pages) with Associated SAS software printout
link: https://drive.google.com/file/d/0B0G6ga3ykYRHcGg3a2pkWlBLZG8/view

j. The worksheet answers.
link: https://drive.google.com/file/d/0B0G6ga3ykYRHR3ViWl9wUmJWblU/view?usp=sharing
-------------------------------------------------------------------------------------------------------------------
Problems 4 and 7.  Analysis of Categorical Data

We will be testing for relationships among the row and column variables in cross classification frequency tables.  We will use a new testing distribution.  So far we have used Z, t, and F.  Now we add the Chi Square distribution. 

a. Intro to the Chi Square Distribution.
    link

b. Textbook reference:
    link

c.  Example of an analysis of a 2 x 3 Table.  Problem 7 is also a 2 x 3 table.  Notice this analysis               procedure uses the Chi Square Distribution  https://youtu.be/L1QPBGoDmT0

d. More details about the Chi Square Distribution.  Using the Chi Square table and using software.
    This gives information on drawing rejections regions for Chi Square tests and figuring out                  p-values with book tables.  Software is also discussed.    https://youtu.be/HwD7ekD5l0g

e. A Chi-Square TableChi-Square table

f. Review pages 602-607 in the book.  I would pay particular attention to example 14.5
------------------------------------------------------------------------------------------------
Problem 5.  The Non Parametric Kruskal Wallis Procedure.
When we want to compare 2 or more groups and the assumptions of the t test and anova are not met a plan b is a non parametric procedure.  There are several such procedures and we are going to focus on the Kruskal- Wallis.  Basically to get around the assumption problem we do an analysis on the ranks of the data

a.  A video of a guy doing a really good job explaining the procedure.  This problem he is doing is very similar to question 5 on the exam.  Notice that the Kruskal - Wallis procedure also uses the Chi Square Distribution with df = k - 1 , where k is the number of groups being comparedhttps://youtu.be/q1D4Di1KWLc

b. The textbook goes through an easy to follow example of comparing four groups with the KW procedure on pages 650-654.  nonparametric book reference link

c. Text book problem solutions by H.GTextbook problems 15.33 and 15.37

Friday, April 17, 2020

The Final Exam

Hello Biostat 1 Students.

I hope you are doing ok in this strange time.  It has been a challenge for me.

I have posted the exam scores for exam 2 on the class blog:
DKWBiostat1.blogspot.com

Here is what I want to do for the final exam.  I am going to send the exam to you on or before Monday April 20.  I want you to do as you did for exam 2, that is, print it, fill in your answers, scan it, and email it back to me.  

This will be somewhat different than exam 2 in that you have until Friday May 8 at 5pm to email the exam to me.  This means you will have over 2 weeks to work on the exam.

The exam will cover: t-test, one way analysis of variance, simple linear regression, categorical analysis, and the Kruskal Wallis nonparametric procedure.  

These topics are in our textbook and I will continue to post new material to the class blog to help you study these topics.  The t-test will be kind of a review from chapter 10.  

Best wishes.
KW

Wednesday, April 15, 2020

Exam 2 Results. Nice Work.

ID           exam2
3059744
90
3062056
92.5
3050454
100
3058110
95
3061256
95
3016021
97.5
1138133
100
3066593
100
3042185
100
3064615
100
3036471
80
3063325
100

Tuesday, March 31, 2020

March 31, 2020 Update

Hello All.

  • I am working on additions to our class blog with a few more video presentations since we are likely not meeting in person for the rest of this spring semester.
  • Look for those updates on the class blog.  I will send out exam 2 as a take home test on April 2.
  • Exam 2 covers the material we covered from chapters 8, 9, and 10.
  • Please print it, fill in your answers by hand, scan it, and email it back to me.  I would like to receive your exam by 6pm on Sunday April 5.
  • We will then proceed with the last third of the course.  I have begun to update the blog with video material and exercises.
  • The final exam will also be take home.  We will administrate it just like exam 2, in a 'take home exam' format.
  • Check the blog for updates.
  • Take care of yourselves and feel free to email me or Heath.


KW

thex
https://drive.google.com/open?id=1mfOeEaf6fk49j-23RZgUPZuLiidXzKcV

Chapter 12. Simple Linear Regression and Correlation. A topic on the final exam not exam 2. (This Chapter 12 Online Presentation is Still Under Construction)

Chapter 12 Topics.

Chapter 12 Textbook Reference from our B1 Text
link: https://drive.google.com/file/d/1pXBOqJPuLJG-BKSe3hPsbK1ne62suJ3T/view?usp=sharing

1. Intro to Linear Regression and Correlation Coefficient (r).
OpenStax Version
(A short 4 min video, at minute 3 a quick intro to 
Pearson's Correlation Coefficient is presented)
link: https://youtu.be/mPvtZhdPBhQ

2. Inference About the Slope b1, and Understanding Regression Output
from Software. OpenStax Version
link: https://youtu.be/depiT-hTaGA

3. Examples of Outliers in Regression. Discussion of 'Leverage' and 'Influence'
in a Regression Analysis.
link: https://youtu.be/jZEKAlo1E54

4. Interpretation of B0, B1, assumptions for linear regression, and R-Squared.
link: https://youtu.be/z8DmwG2G4Qc

5. Introduction to Linear Regression Marin Stats Version.
link: https://youtu.be/vblX9JVpHE8

6. Intro to Linear Regression JB Stats Version
link: https://youtu.be/KsVBBJRb9TE

7. Discussion of Linear Regression that Puts Several Concepts Together
JB Stats Version
link: https://youtu.be/xIDjj6ZyFuw

8.Practice Problems and Materials.

a. Potency and Temperature Worksheet:
The R Software Printout.
link: https://drive.google.com/file/d/0B0G6ga3ykYRHWnNwVnllTlhwcHc/view
The worksheet (last pages) with Associated SAS software printout
link: https://drive.google.com/file/d/0B0G6ga3ykYRHcGg3a2pkWlBLZG8/view
The worksheet answers.
link: https://drive.google.com/file/d/0B0G6ga3ykYRHR3ViWl9wUmJWblU/view?usp=sharing

Thursday, March 26, 2020

Chapter 11. The One Way Analysis of Variance Procedure to Compare 2 or More Population Means. We cover only the first part of chapter 11 (pg 447-465) . This Material will NOT be on exam 2, but will be a topic on the final exam.


1. Introduction to the AOV Procedure

a.  Introduction to One Way Analysis of Variance (ANOVA)
link: https://youtu.be/QUQ6YppWCeg

b. ANOVA. An Intro to Formulas
link: https://youtu.be/fFnOD7KBSbw

c.  A Numerical Example of a One Way ANOVA
link: https://youtu.be/WUoVftXvjiQ

d. Comparing Among k Means in ANOVA when F - Test is Significant.  First Basic Procedure.
link: https://youtu.be/kO8t_q-AXHE

e. A quick intro to Tukeys multiple comparison procedure.  A common approach more popular than LSD procedure discussed in d. above.
link: https://youtu.be/lpdFr5SZR0Q

e. Finding the Approximate P-Value from F - test Using Textbook F - tables
link: https://youtu.be/XdZ7BRqznSA

f. A link to our textbook reference for chapter 11
link: https://drive.google.com/file/d/19Td_GXTWTIi_G9IL-Uj_qcXyP_4Be2IL/view



2. Book Exercises for One Way Anova.  Problems 11.12 (a,b,c) , 11.13 (b,d) , 11.14 (a,b)
link: https://drive.google.com/file/d/1Zcr5ZO77L_AVu5Sv1kX65iU5XRZC_fle/view?usp=sharing

a. Eric's handwritten solutions to the textbook problems 11.12 (a,b,c) , 11.13 (b,d) , 11.14 (a,b) 
  link: https://drive.google.com/file/d/0B0G6ga3ykYRHUnRfYUxjaHMtVzQ/view

The following are R printouts with means and the Tukey procedure to compare all possible pairs.
They are meant to enrich the textbook aov tables that go with the exercises in the book.
b. R printout with Tukey procedure for problem 12
link
c. R printout with Tukey procedure for problem 13
link
d. R printout with Tukey procedure for problem 14
link

3.  AOV worksheets

a.  Worksheet 1
 link






Update March 26, 2020 to round out and complete Chapter 10: Small Sample t-tests on Population Means. If you work your way through this list of presentations you should be able to complete the chapter 10 topics that will be on take home exam 2 that I will provide you on April 4


Chapter 10 Topics to review.

1. Assumptions for t-test
https://dkwbiostat1.blogspot.com/2020/03/assumptions-for-use-of-t-distribution.html

2. Introduction to t-test for one population mean
https://dkwbiostat1.blogspot.com/2020/03/introduction-to-t-test-for-population.html
https://youtu.be/kQ4xcx6N0o4  (A second example)

3. Using the t-table in the book to find approximate p-values
https://dkwbiostat1.blogspot.com/2020/03/using-t-table-to-find-approximate-p.html

4. Comparing two independent group population means
https://dkwbiostat1.blogspot.com/2019/10/intro-to-comparing-two-population-means.html

5. The paired t-test design
https://dkwbiostat1.blogspot.com/2020/03/the-paired-t-test-to-compare-two.html

6. Formulas for hypothesis testing and confidence intervals for both large sample scenarios
(chapters 8 and 9) and small sample scenarios (chapter 10).  This is handy because the test statistics and CI formulas are organized and in one document.
https://dkwbiostat1.blogspot.com/2020/03/chapters-89-and-10-confidence-interval.html

7.  A worksheet that has examples of all three small sample scenarios from chapter 10
https://dkwbiostat1.blogspot.com/2020/03/four-chapter-10-t-distribution.html
Here are the answers: 
https://dkwbiostat1.blogspot.com/2020/03/answers-to-four-chapter-10-t.html

8. If you wish more practice, here is a link to additional textbook exercises and my handwritten solutions at the bottom of the list 
https://dkwbiostat1.blogspot.com/2020/03/chapter-10-exercises-and-answers-from.html

Monday, March 9, 2020

Using the T Table to find Approximate P-Values. Short Video.

https://youtu.be/tI6mdx3s0zk

Introduction to the T Test for a Population Mean. Video from JB Stats.

https://youtu.be/T9nI6vhTU1Y

Assumptions for the Use of the T Distribution. Short Video.

https://youtu.be/U1O4ZFKKD1k

Chapter 10 Exercises and Answers from Mendenhall Reference.



Click below to view these problems and the book answer page
https://drive.google.com/file/d/18lBwAl_HFwOqqauXca8rnVDkDq6kUqzw/view?usp=sharing

One Population Mean (Small Sample)

10.1
10.3
10.5 c (alpha=.01)
10.7
10.13
10.14

Mu1 - Mu2 (Independent Groups Small Sample)

10.19
10.21  (Summary Stats Provided)
10.25   (Summary Stats Provided)

Mu(d)  (Paired Difference Design Small Sample)

10.37
10.43 a,b  (Two tail test)

Click below for a link to a hand draft copy of the answers to above problems:

https://drive.google.com/file/d/1f8a-DvyII0eDaPxbqXfzVzaKmD_9u7iw/view?usp=sharing

Answers to the Four Chapter 10 t distribution Worksheet exercises.

click

Four Chapter 10 T Distribution Worksheet Problems to Be Discussed in Class. (It would be good to print this and attempt)

click

Brief Story of William Gosset.


https://youtu.be/U9Wr7VEPGXA

Chapters 8,9, and 10 Confidence Interval and Test Statistic Formulas (Very good for exam review)

click

T Distribution Tail Area Calculator (and other stat distribution calculators)

http://vassarstats.net/tabs.html#t

Graph of Various t Distributions for Comparison


Tuesday, March 3, 2020

Chapter 9 Problems from Mendenhall Book (aka "B1 Book)

Chapter 9 Problems (Use alpha = 0.05 unless stated otherwise)

Link to view this chapter on the web
https://drive.google.com/file/d/1-aEHZeqOWIwfPGPF39d2eUCmFgPzZzv6/view

One Population Mean (361)

9.11
9.15 a
9.16
9.17

Difference in Two Population Means (page 366)

9.19
9.21
9.23 a b
9.29 a b

One Population Proportion (page 371)

9.31
9.34
9.39
9.41

Difference in Two Population Proportions (page 376)

9.45
9.47

Chapter 9 Large Sample Size Hypothesis Tests Worksheet Answers

https://drive.google.com/file/d/0B0G6ga3ykYRHMG1qNXdxMXlLLWM/view?usp=sharing

Hypothesis Test Worksheet Chapter 9 Large Sample Cases.

click

Short 10 Min Video on the P-Value Approach in Hypothesis Testing.

https://youtu.be/m6sGjWz2CPg

Short 10 Min Video on the Rejection Region Approach in Hypothesis Testing

https://youtu.be/60x86lYtWI4

JB Stats Video. Introduction to Hypothesis Testing.

https://youtu.be/tTeMYuS87oU

Tuesday, February 25, 2020

T Table for Reference

https://drive.google.com/file/d/0B0G6ga3ykYRHYzVFa1l6NDJ1enM/view?usp=sharing

Confidence Interval Worksheet. Chapter 8 Classroom Exercise

click

Chapter 8 Large Sample Confidence Interval Worksheet Answers


https://drive.google.com/file/d/0B0G6ga3ykYRHcnZ3QmRCcXNLeTg/view?usp=sharing

Introduction to the Idea of Confidence Intervals. Short Video

https://youtu.be/27iSnzss2wM

A 5 Minute Video Reviewing How to Find the Correct Z Value When Constructing Large Sample Confidence Intervals for Means and Proportions


https://youtu.be/grodoLzThy4

Large Sample Confidence Interval Problems. CI Estimation for Mu, P, Mu1 - Mu2 and P1 - P2. Chapter 8 book link is included for easy reference.


Book Chapter Link:
https://drive.google.com/open?id=1o1saTMreAIdypKALxo9Kx-cRFFDuwibL

Answers from back of book for selected problems:
https://drive.google.com/open?id=1499pQuOcXEPDK-rI7Wgv0P0no5YHlC5x

CIs on the population mean large sample

8.23
8.31
8.37

CIs on the population proportion large sample

8.25
8.35 a.
8.38 a.


Large Sample CI on Mu1-Mu2 Problems from Mendenhall Book

Book pages 321-322

8.39
8.41
8.43
8.49


Large Sample CI on P1-P2 Problems from Mendenhall Book

Book pages 327-328

8.55
8.57
8.59
8.61


Chapter 8 Confidence Interval Formulas

https://drive.google.com/file/d/0B0G6ga3ykYRHWnJkd0lkY2lpMXM/view?usp=sharing

Confidence Interval Idea Simulation. We need some luck with Adobe Flash Player for this to work

http://video.franklin.edu/Franklin/Math/215/conf_interval/conf_interval.html

Tuesday, February 18, 2020

A Very Fast Talking Video About the Central Limit Theorem


https://youtu.be/EXKUNccqL6Y

Standard Normal Z Table. Please print out a copy for yourself for Exam 1 and exercises.

https://drive.google.com/file/d/1fLwhbO3jiP5QySeca5dktanR2Xs4XlFD/view?usp=sharing

Biostat 1 Exam 1 Checklist 2020



Biostat 1 Exam 1 Checklist 2020

1. Boxplot properties and attributes. (outliers, quartiles, min, and max)

2. Summary statistics (mean, mode, median, Q1, Q2, Q3, IQR, sd, variance, range)

3. Empirical Rule (68%, 95%, ‘practically all’)

4. Probability (2x2 table, union, intersection, conditional, mutually exclusive)

5. Binomial distribution (pdf, mean, sd, var, use of pdf table)

6. Poisson distribution (pfd, mean, sd, var, use of pdf table)

7. Standard Normal Z distribution (find probabilities using table)

8. Non-Standard Normal (find probabilities using table)

9.  Find percentiles for Normal Distributions.

10. Using the Normal Distribution to approximate Binomial probabilities.

11.  Bring a calculator (or one on your phone), PENCIL, Z table,
      and one sheet of paper with anything you wish written on it.

      We will provide Binomial and Poisson tables for the exam.







Thursday, February 6, 2020

Short Video on Using the Z table to find Normal Distribution.

https://youtu.be/-UljIcq_rfc

Selected Chapter 6 Normal Distribution Problems. Handwritten.

https://drive.google.com/file/d/0B0G6ga3ykYRHVnc1NFh1dEt5MWs/view?usp=sharing

An Introduction to the Normal Distribution. A 6 Min Video.


https://youtu.be/iYiOVISWXS4

Standard Normal Distribution Z table from book

https://drive.google.com/file/d/0B0G6ga3ykYRHZWpreEpuY1FCUjQ/view?usp=sharing

Introduction to a Continuous Probability Distribution. A Short 5 Min Video

https://youtu.be/OWSOhpS00_s

Textbook: Additional Materials for Study of the Normal Probability Distribution. Exercises at the end. Standard Normal Z Exercises are 6.1-6.11 on Page 234.

https://drive.google.com/open?id=1YVbXo0lOEBqP9u8o-r_SQyDDmpQQtzCt

Tuesday, January 21, 2020

Online R B1 Demos

https://dkeithwilliams.github.io/onlineRclass/

senic=read.csv("http://www.ics.uci.edu/~sternh/courses/210/senic.csv",header=T)
p19=c(5, 2, 3, 6, 1, 2, 4, 5, 1, 3)
p19^2
sum(p19)
(sum(p19))^2
sum(p19^2)
s2=(130-(1024/10))/(10-1)
sqrt(s2)
var(p19)
sd(p19)

p45=c(3, 9, 10, 2, 6, 7, 5, 8, 6, 6, 4, 9, 22)
sort(p45)
quantile(p45,probs = c(.25,.50,.75),type=6)

l25=.25*(13+1)
l25
l75=.75*(13+1)
l75

9+1.5*4.5
4.5-1.5*4.5