Linear Correlation and Regression Analysis

Size: px
Start display at page:

Download "Linear Correlation and Regression Analysis"

Transcription

1 Linear Correlation and Regression Analysis

2 Set Up the Calculator 2 nd CATALOG D arrow down DiagnosticOn ENTER ENTER

3 SCATTER DIAGRAM

4 Positive Linear Correlation

5 Positive Correlation Variables will tend to pair as high measurements for x with high measurements for y and low x with low y

6 Negative correlation

7 Negative Correlation Variables will tend to pair high x measurements with low measurements for y and low x with high y.

8 No correlation

9 r THE COEFFICIENT OF LINEAR CORRELATION Pearson s Correlation Coefficient, r, measures the strength of a linear relationship between two variables for a sample. n x n 2 xy x y 2 2 x n y y 2

10 Interpreting the Values of r r = 1 Perfect Positive Correlation (Positive Slope)

11 Interpreting the Values of r r = -1 Perfect Negative correlation (Negative Slope)

12 Interpreting the Values of r r = 0 no correlation

13 Possible Values of r 1 r 1 strong correlation weak correlation r = -1 r = 0 r = +1 l r = r = r = 0.07 r = 0.69

14 Calculate r

15 1-Var Stat TEMP1 and TEMP2

16 What is xy

17

18 TESTING THE SIGNIFICANCE OF THE CORRELATION COEFFICIENT Is there a significant correlation between: HS average and success in college? Hours of T.V. watched and IQ score? Age and blood pressure? Advertising expenditures and sales? Mothers shoe size and daughters IQ?

19 Caution #2: Correlation Doesn t Indicate a Cause-and-Effect Relationship The number of storks nesting in various European towns in the early 1900 s and the number of human babies born in the same towns had a very high correlation. However, we can t conclude that an increase in the number of storks will cause an increase in the number of babies.

20 TESTING THE SIGNIFICANCE OF THE CORRELATION COEFFICIENT The population correlation coefficient is symbolized by Greek letter rho: ρ The sample correlation coefficient r is an estimate of the population correlation coefficient.

21 Null Hypothesis Form Ho: The population correlation coefficient is equal to zero. Ho: ρ = 0 There is no linear correlation between the two variables. r 0

22 3 Forms of the Alternative Hypothesis Ha:

23 Interpretation of Ha: Form #1 Ha: ρ > 0 There is a positive correlation between the two variables.

24 General Solution (positive) 1TT > r 0 r r formula

25 Interpretation of Ha: Form #2 Ha: ρ < 0 There is a negative correlation between the two variables.

26 General Solution (negative) 1TT > r formula r 0 r

27 Interpretation of Ha: Form #3 Ha: ρ 0 There is a (some) correlation between the two variables.

28 General Solution (some) 2TT > rformula r r 0 r

29 Degrees of freedom for testing the correlation coefficient Subtract two from the number of pairs of data df = n 2

30 Coefficient of Determination r 2 is the influence that the variance in the independent variable has on the dependent variable. 1 r 2 is unexplained.

31 Determine the variables grades vs. study hours independent is dependent is

32 Determine the variables credits vs. age sun light vs. height of a plant bike vs. presidents gift vs. work

33 LINEAR REGRESSION ANALYSIS Regression Line Formula: y' = a + bx y' is the predicted value of y, the dependent variable, given the value of x, the independent variable.

34 Example A scientists wants to determine if there is a linear relationship between the amount of rainfall in May and the number of mosquitoes. For each of the selected years, data pairs have listed in the table.

35 YEAR Sample data MOSQUITO INDEX RAIN

36 Enter data

37 Procedure a) Construct a scatter diagram. b) Calculate the sample correlation coefficient, r. c) Determine if r is significant at α = 1%.

38 Procedure 2 d) Find r and interpret its meaning. e) Determine the regression equation, y'. f) Using the regression equation, predict the mosquito population index if we have 3.1 inches of rain in May.

39 Scatter Plot

40 Perform Linear Reg T Test CORRECT ORDER?

41 Select Ha; Set Y1 (once)

42 Calculate, arrow down Record : p-value, a, b, r 2 and r

43 Interpretations r = : close to r = 1 therefore a Strong Positive correlation. p-value is less then α = 1%, so reject Ho and accept Ha. There is a correlation between rainfall and the mosquito population index.

44 r Coefficient of determination: 87.22% of the dependent variable variation is attributed to variation in the independent variable; 12.78% is unexplained.

45 Regression Equation y' = a + b (x) y' = (x) Prediction for the mosquito index: Substitute rain = 3.1 inches y' =

46 Confidence in Prediction of population index Since r = , is very close to r = 1 (a perfect correlation), there is a high level of confidence in the accuracy of the prediction.

47 Interpolation vs. Extrapolation Use a rain prediction = 6739 Substitute Y1(6739) Result = How much confidence?

48 Using the Regression Line BLOOD PRESSURE Interpolate if maximum weight collected 256 lbs BODY WEIGHT

49 Using the Regression Line BLOOD PRESSURE Interpolate Extrapolate 256 lbs 9842 BODY WEIGHT

50 Redo Scatter Plot for Regression line

51

52

53 Calculate correlation coefficient, r for Rain & Mosquito Data r n x n 2 xy x y 2 2 x n y y 2 calculated r is the EV

54 Determine critical page 810 table V value from Pairs of mosquito & rain values, n= 6 r Subtract two from the number of pairs of data values to generate Degrees of freedom: df = n 2 = 4 We were given α = 1% 2 Tail

55 critical r 0.92 calculated r

56

4.1 Introduction. 4.2 The Scatter Diagram. Chapter 4 Linear Correlation and Regression Analysis

4.1 Introduction. 4.2 The Scatter Diagram. Chapter 4 Linear Correlation and Regression Analysis 4.1 Introduction Correlation is a technique that measures the strength (or the degree) of the relationship between two variables. For example, we could measure how strong the relationship is between people

More information

Correlation Analysis

Correlation Analysis Simple Regression Correlation Analysis Correlation analysis is used to measure strength of the association (linear relationship) between two variables Correlation is only concerned with strength of the

More information

y n 1 ( x i x )( y y i n 1 i y 2

y n 1 ( x i x )( y y i n 1 i y 2 STP3 Brief Class Notes Instructor: Ela Jackiewicz Chapter Regression and Correlation In this chapter we will explore the relationship between two quantitative variables, X an Y. We will consider n ordered

More information

Correlation and Regression

Correlation and Regression A. The Basics of Correlation Analysis 1. SCATTER DIAGRAM A key tool in correlation analysis is the scatter diagram, which is a tool for analyzing potential relationships between two variables. One variable

More information

Can you tell the relationship between students SAT scores and their college grades?

Can you tell the relationship between students SAT scores and their college grades? Correlation One Challenge Can you tell the relationship between students SAT scores and their college grades? A: The higher SAT scores are, the better GPA may be. B: The higher SAT scores are, the lower

More information

determine whether or not this relationship is.

determine whether or not this relationship is. Section 9-1 Correlation A correlation is a between two. The data can be represented by ordered pairs (x,y) where x is the (or ) variable and y is the (or ) variable. There are several types of correlations

More information

AMS7: WEEK 7. CLASS 1. More on Hypothesis Testing Monday May 11th, 2015

AMS7: WEEK 7. CLASS 1. More on Hypothesis Testing Monday May 11th, 2015 AMS7: WEEK 7. CLASS 1 More on Hypothesis Testing Monday May 11th, 2015 Testing a Claim about a Standard Deviation or a Variance We want to test claims about or 2 Example: Newborn babies from mothers taking

More information

Inferences for Correlation

Inferences for Correlation Inferences for Correlation Quantitative Methods II Plan for Today Recall: correlation coefficient Bivariate normal distributions Hypotheses testing for population correlation Confidence intervals for population

More information

Statistics Introductory Correlation

Statistics Introductory Correlation Statistics Introductory Correlation Session 10 oscardavid.barrerarodriguez@sciencespo.fr April 9, 2018 Outline 1 Statistics are not used only to describe central tendency and variability for a single variable.

More information

The Chi-Square Distributions

The Chi-Square Distributions MATH 03 The Chi-Square Distributions Dr. Neal, Spring 009 The chi-square distributions can be used in statistics to analyze the standard deviation of a normally distributed measurement and to test the

More information

Lecture 11: Simple Linear Regression

Lecture 11: Simple Linear Regression Lecture 11: Simple Linear Regression Readings: Sections 3.1-3.3, 11.1-11.3 Apr 17, 2009 In linear regression, we examine the association between two quantitative variables. Number of beers that you drink

More information

Regression Analysis II

Regression Analysis II Regression Analysis II Measures of Goodness of fit Two measures of Goodness of fit Measure of the absolute fit of the sample points to the sample regression line Standard error of the estimate An index

More information

The Chi-Square Distributions

The Chi-Square Distributions MATH 183 The Chi-Square Distributions Dr. Neal, WKU The chi-square distributions can be used in statistics to analyze the standard deviation σ of a normally distributed measurement and to test the goodness

More information

Correlation. A statistics method to measure the relationship between two variables. Three characteristics

Correlation. A statistics method to measure the relationship between two variables. Three characteristics Correlation Correlation A statistics method to measure the relationship between two variables Three characteristics Direction of the relationship Form of the relationship Strength/Consistency Direction

More information

Correlation. We don't consider one variable independent and the other dependent. Does x go up as y goes up? Does x go down as y goes up?

Correlation. We don't consider one variable independent and the other dependent. Does x go up as y goes up? Does x go down as y goes up? Comment: notes are adapted from BIOL 214/312. I. Correlation. Correlation A) Correlation is used when we want to examine the relationship of two continuous variables. We are not interested in prediction.

More information

regression analysis is a type of inferential statistics which tells us whether relationships between two or more variables exist

regression analysis is a type of inferential statistics which tells us whether relationships between two or more variables exist regression analysis is a type of inferential statistics which tells us whether relationships between two or more variables exist sales $ (y - dependent variable) advertising $ (x - independent variable)

More information

Six Sigma Black Belt Study Guides

Six Sigma Black Belt Study Guides Six Sigma Black Belt Study Guides 1 www.pmtutor.org Powered by POeT Solvers Limited. Analyze Correlation and Regression Analysis 2 www.pmtutor.org Powered by POeT Solvers Limited. Variables and relationships

More information

(ii) Scan your answer sheets INTO ONE FILE only, and submit it in the drop-box.

(ii) Scan your answer sheets INTO ONE FILE only, and submit it in the drop-box. FINAL EXAM ** Two different ways to submit your answer sheet (i) Use MS-Word and place it in a drop-box. (ii) Scan your answer sheets INTO ONE FILE only, and submit it in the drop-box. Deadline: December

More information

Review 6. n 1 = 85 n 2 = 75 x 1 = x 2 = s 1 = 38.7 s 2 = 39.2

Review 6. n 1 = 85 n 2 = 75 x 1 = x 2 = s 1 = 38.7 s 2 = 39.2 Review 6 Use the traditional method to test the given hypothesis. Assume that the samples are independent and that they have been randomly selected ) A researcher finds that of,000 people who said that

More information

Lecture 14. Analysis of Variance * Correlation and Regression. The McGraw-Hill Companies, Inc., 2000

Lecture 14. Analysis of Variance * Correlation and Regression. The McGraw-Hill Companies, Inc., 2000 Lecture 14 Analysis of Variance * Correlation and Regression Outline Analysis of Variance (ANOVA) 11-1 Introduction 11-2 Scatter Plots 11-3 Correlation 11-4 Regression Outline 11-5 Coefficient of Determination

More information

Lecture 14. Outline. Outline. Analysis of Variance * Correlation and Regression Analysis of Variance (ANOVA)

Lecture 14. Outline. Outline. Analysis of Variance * Correlation and Regression Analysis of Variance (ANOVA) Outline Lecture 14 Analysis of Variance * Correlation and Regression Analysis of Variance (ANOVA) 11-1 Introduction 11- Scatter Plots 11-3 Correlation 11-4 Regression Outline 11-5 Coefficient of Determination

More information

Chapter 10. Correlation and Regression. McGraw-Hill, Bluman, 7th ed., Chapter 10 1

Chapter 10. Correlation and Regression. McGraw-Hill, Bluman, 7th ed., Chapter 10 1 Chapter 10 Correlation and Regression McGraw-Hill, Bluman, 7th ed., Chapter 10 1 Example 10-2: Absences/Final Grades Please enter the data below in L1 and L2. The data appears on page 537 of your textbook.

More information

7.2 One-Sample Correlation ( = a) Introduction. Correlation analysis measures the strength and direction of association between

7.2 One-Sample Correlation ( = a) Introduction. Correlation analysis measures the strength and direction of association between 7.2 One-Sample Correlation ( = a) Introduction Correlation analysis measures the strength and direction of association between variables. In this chapter we will test whether the population correlation

More information

Chapter 10. Correlation and Regression. McGraw-Hill, Bluman, 7th ed., Chapter 10 1

Chapter 10. Correlation and Regression. McGraw-Hill, Bluman, 7th ed., Chapter 10 1 Chapter 10 Correlation and Regression McGraw-Hill, Bluman, 7th ed., Chapter 10 1 Chapter 10 Overview Introduction 10-1 Scatter Plots and Correlation 10- Regression 10-3 Coefficient of Determination and

More information

Business Statistics. Chapter 14 Introduction to Linear Regression and Correlation Analysis QMIS 220. Dr. Mohammad Zainal

Business Statistics. Chapter 14 Introduction to Linear Regression and Correlation Analysis QMIS 220. Dr. Mohammad Zainal Department of Quantitative Methods & Information Systems Business Statistics Chapter 14 Introduction to Linear Regression and Correlation Analysis QMIS 220 Dr. Mohammad Zainal Chapter Goals After completing

More information

Introduction to Statistics for the Social Sciences Review for Exam 4 Homework Assignment 27

Introduction to Statistics for the Social Sciences Review for Exam 4 Homework Assignment 27 Introduction to Statistics for the Social Sciences Review for Exam 4 Homework Assignment 27 Name: Lab: The purpose of this worksheet is to review the material to be represented in Exam 4. Please answer

More information

11 Correlation and Regression

11 Correlation and Regression Chapter 11 Correlation and Regression August 21, 2017 1 11 Correlation and Regression When comparing two variables, sometimes one variable (the explanatory variable) can be used to help predict the value

More information

Chapter 12 : Linear Correlation and Linear Regression

Chapter 12 : Linear Correlation and Linear Regression Chapter 1 : Linear Correlation and Linear Regression Determining whether a linear relationship exists between two quantitative variables, and modeling the relationship with a line, if the linear relationship

More information

Describing Bivariate Relationships

Describing Bivariate Relationships Describing Bivariate Relationships Bivariate Relationships What is Bivariate data? When exploring/describing a bivariate (x,y) relationship: Determine the Explanatory and Response variables Plot the data

More information

Area1 Scaled Score (NAPLEX) .535 ** **.000 N. Sig. (2-tailed)

Area1 Scaled Score (NAPLEX) .535 ** **.000 N. Sig. (2-tailed) Institutional Assessment Report Texas Southern University College of Pharmacy and Health Sciences "An Analysis of 2013 NAPLEX, P4-Comp. Exams and P3 courses The following analysis illustrates relationships

More information

Chapter 12 - Part I: Correlation Analysis

Chapter 12 - Part I: Correlation Analysis ST coursework due Friday, April - Chapter - Part I: Correlation Analysis Textbook Assignment Page - # Page - #, Page - # Lab Assignment # (available on ST webpage) GOALS When you have completed this lecture,

More information

Example: Forced Expiratory Volume (FEV) Program L13. Example: Forced Expiratory Volume (FEV) Example: Forced Expiratory Volume (FEV)

Example: Forced Expiratory Volume (FEV) Program L13. Example: Forced Expiratory Volume (FEV) Example: Forced Expiratory Volume (FEV) Program L13 Relationships between two variables Correlation, cont d Regression Relationships between more than two variables Multiple linear regression Two numerical variables Linear or curved relationship?

More information

Objectives Simple linear regression. Statistical model for linear regression. Estimating the regression parameters

Objectives Simple linear regression. Statistical model for linear regression. Estimating the regression parameters Objectives 10.1 Simple linear regression Statistical model for linear regression Estimating the regression parameters Confidence interval for regression parameters Significance test for the slope Confidence

More information

5.1 Bivariate Relationships

5.1 Bivariate Relationships Chapter 5 Summarizing Bivariate Data Source: TPS 5.1 Bivariate Relationships What is Bivariate data? When exploring/describing a bivariate (x,y) relationship: Determine the Explanatory and Response variables

More information

Stats Review Chapter 14. Mary Stangler Center for Academic Success Revised 8/16

Stats Review Chapter 14. Mary Stangler Center for Academic Success Revised 8/16 Stats Review Chapter 14 Revised 8/16 Note: This review is meant to highlight basic concepts from the course. It does not cover all concepts presented by your instructor. Refer back to your notes, unit

More information

Chapter 12 - Lecture 2 Inferences about regression coefficient

Chapter 12 - Lecture 2 Inferences about regression coefficient Chapter 12 - Lecture 2 Inferences about regression coefficient April 19th, 2010 Facts about slope Test Statistic Confidence interval Hypothesis testing Test using ANOVA Table Facts about slope In previous

More information

df=degrees of freedom = n - 1

df=degrees of freedom = n - 1 One sample t-test test of the mean Assumptions: Independent, random samples Approximately normal distribution (from intro class: σ is unknown, need to calculate and use s (sample standard deviation)) Hypotheses:

More information

Unit 6 - Introduction to linear regression

Unit 6 - Introduction to linear regression Unit 6 - Introduction to linear regression Suggested reading: OpenIntro Statistics, Chapter 7 Suggested exercises: Part 1 - Relationship between two numerical variables: 7.7, 7.9, 7.11, 7.13, 7.15, 7.25,

More information

Chapter 16. Simple Linear Regression and dcorrelation

Chapter 16. Simple Linear Regression and dcorrelation Chapter 16 Simple Linear Regression and dcorrelation 16.1 Regression Analysis Our problem objective is to analyze the relationship between interval variables; regression analysis is the first tool we will

More information

Chapter 16. Simple Linear Regression and Correlation

Chapter 16. Simple Linear Regression and Correlation Chapter 16 Simple Linear Regression and Correlation 16.1 Regression Analysis Our problem objective is to analyze the relationship between interval variables; regression analysis is the first tool we will

More information

Chapter 14 Simple Linear Regression (A)

Chapter 14 Simple Linear Regression (A) Chapter 14 Simple Linear Regression (A) 1. Characteristics Managerial decisions often are based on the relationship between two or more variables. can be used to develop an equation showing how the variables

More information

A discussion on multiple regression models

A discussion on multiple regression models A discussion on multiple regression models In our previous discussion of simple linear regression, we focused on a model in which one independent or explanatory variable X was used to predict the value

More information

Chapter 4 Describing the Relation between Two Variables

Chapter 4 Describing the Relation between Two Variables Chapter 4 Describing the Relation between Two Variables 4.1 Scatter Diagrams and Correlation The is the variable whose value can be explained by the value of the or. A is a graph that shows the relationship

More information

Correlation and Linear Regression

Correlation and Linear Regression Correlation and Linear Regression Correlation: Relationships between Variables So far, nearly all of our discussion of inferential statistics has focused on testing for differences between group means

More information

LOOKING FOR RELATIONSHIPS

LOOKING FOR RELATIONSHIPS LOOKING FOR RELATIONSHIPS One of most common types of investigation we do is to look for relationships between variables. Variables may be nominal (categorical), for example looking at the effect of an

More information

Test 3 Practice Test A. NOTE: Ignore Q10 (not covered)

Test 3 Practice Test A. NOTE: Ignore Q10 (not covered) Test 3 Practice Test A NOTE: Ignore Q10 (not covered) MA 180/418 Midterm Test 3, Version A Fall 2010 Student Name (PRINT):............................................. Student Signature:...................................................

More information

Correlation A relationship between two variables As one goes up, the other changes in a predictable way (either mostly goes up or mostly goes down)

Correlation A relationship between two variables As one goes up, the other changes in a predictable way (either mostly goes up or mostly goes down) Two-Variable Statistics Correlation A relationship between two variables As one goes up, the other changes in a predictable way (either mostly goes up or mostly goes down) Positive Correlation As one variable

More information

" M A #M B. Standard deviation of the population (Greek lowercase letter sigma) σ 2

 M A #M B. Standard deviation of the population (Greek lowercase letter sigma) σ 2 Notation and Equations for Final Exam Symbol Definition X The variable we measure in a scientific study n The size of the sample N The size of the population M The mean of the sample µ The mean of the

More information

Lecture 15: Chapter 10

Lecture 15: Chapter 10 Lecture 15: Chapter 10 C C Moxley UAB Mathematics 20 July 15 10.1 Pairing Data In Chapter 9, we talked about pairing data in a natural way. In this Chapter, we will essentially be discussing whether these

More information

Section 9.4. Notation. Requirements. Definition. Inferences About Two Means (Matched Pairs) Examples

Section 9.4. Notation. Requirements. Definition. Inferences About Two Means (Matched Pairs) Examples Objective Section 9.4 Inferences About Two Means (Matched Pairs) Compare of two matched-paired means using two samples from each population. Hypothesis Tests and Confidence Intervals of two dependent means

More information

Important note: Transcripts are not substitutes for textbook assignments. 1

Important note: Transcripts are not substitutes for textbook assignments. 1 In this lesson we will cover correlation and regression, two really common statistical analyses for quantitative (or continuous) data. Specially we will review how to organize the data, the importance

More information

χ test statistics of 2.5? χ we see that: χ indicate agreement between the two sets of frequencies.

χ test statistics of 2.5? χ we see that: χ indicate agreement between the two sets of frequencies. I. T or F. (1 points each) 1. The χ -distribution is symmetric. F. The χ may be negative, zero, or positive F 3. The chi-square distribution is skewed to the right. T 4. The observed frequency of a cell

More information

Inferences for Regression

Inferences for Regression Inferences for Regression An Example: Body Fat and Waist Size Looking at the relationship between % body fat and waist size (in inches). Here is a scatterplot of our data set: Remembering Regression In

More information

Keller: Stats for Mgmt & Econ, 7th Ed July 17, 2006

Keller: Stats for Mgmt & Econ, 7th Ed July 17, 2006 Chapter 17 Simple Linear Regression and Correlation 17.1 Regression Analysis Our problem objective is to analyze the relationship between interval variables; regression analysis is the first tool we will

More information

Chapte The McGraw-Hill Companies, Inc. All rights reserved.

Chapte The McGraw-Hill Companies, Inc. All rights reserved. 12er12 Chapte Bivariate i Regression (Part 1) Bivariate Regression Visual Displays Begin the analysis of bivariate data (i.e., two variables) with a scatter plot. A scatter plot - displays each observed

More information

STATS DOESN T SUCK! ~ CHAPTER 16

STATS DOESN T SUCK! ~ CHAPTER 16 SIMPLE LINEAR REGRESSION: STATS DOESN T SUCK! ~ CHAPTER 6 The HR manager at ACME food services wants to examine the relationship between a workers income and their years of experience on the job. He randomly

More information

Unit 6 - Simple linear regression

Unit 6 - Simple linear regression Sta 101: Data Analysis and Statistical Inference Dr. Çetinkaya-Rundel Unit 6 - Simple linear regression LO 1. Define the explanatory variable as the independent variable (predictor), and the response variable

More information

Correlation and Regression Analysis. Linear Regression and Correlation. Correlation and Linear Regression. Three Questions.

Correlation and Regression Analysis. Linear Regression and Correlation. Correlation and Linear Regression. Three Questions. 10/8/18 Correlation and Regression Analysis Correlation Analysis is the study of the relationship between variables. It is also defined as group of techniques to measure the association between two variables.

More information

Table of z values and probabilities for the standard normal distribution. z is the first column plus the top row. Each cell shows P(X z).

Table of z values and probabilities for the standard normal distribution. z is the first column plus the top row. Each cell shows P(X z). Table of z values and probabilities for the standard normal distribution. z is the first column plus the top row. Each cell shows P(X z). For example P(X.04) =.8508. For z < 0 subtract the value from,

More information

REVIEW 8/2/2017 陈芳华东师大英语系

REVIEW 8/2/2017 陈芳华东师大英语系 REVIEW Hypothesis testing starts with a null hypothesis and a null distribution. We compare what we have to the null distribution, if the result is too extreme to belong to the null distribution (p

More information

Multiple Linear Regression

Multiple Linear Regression Chapter 3 Multiple Linear Regression 3.1 Introduction Multiple linear regression is in some ways a relatively straightforward extension of simple linear regression that allows for more than one independent

More information

Simple Linear Regression

Simple Linear Regression Simple Linear Regression EdPsych 580 C.J. Anderson Fall 2005 Simple Linear Regression p. 1/80 Outline 1. What it is and why it s useful 2. How 3. Statistical Inference 4. Examining assumptions (diagnostics)

More information

Homework 2: Simple Linear Regression

Homework 2: Simple Linear Regression STAT 4385 Applied Regression Analysis Homework : Simple Linear Regression (Simple Linear Regression) Thirty (n = 30) College graduates who have recently entered the job market. For each student, the CGPA

More information

Statistics for Managers using Microsoft Excel 6 th Edition

Statistics for Managers using Microsoft Excel 6 th Edition Statistics for Managers using Microsoft Excel 6 th Edition Chapter 13 Simple Linear Regression 13-1 Learning Objectives In this chapter, you learn: How to use regression analysis to predict the value of

More information

Lecture (chapter 13): Association between variables measured at the interval-ratio level

Lecture (chapter 13): Association between variables measured at the interval-ratio level Lecture (chapter 13): Association between variables measured at the interval-ratio level Ernesto F. L. Amaral April 9 11, 2018 Advanced Methods of Social Research (SOCI 420) Source: Healey, Joseph F. 2015.

More information

Lecture notes on Regression & SAS example demonstration

Lecture notes on Regression & SAS example demonstration Regression & Correlation (p. 215) When two variables are measured on a single experimental unit, the resulting data are called bivariate data. You can describe each variable individually, and you can also

More information

Simple Linear Regression

Simple Linear Regression Simple Linear Regression ST 430/514 Recall: A regression model describes how a dependent variable (or response) Y is affected, on average, by one or more independent variables (or factors, or covariates)

More information

Business Statistics. Lecture 10: Correlation and Linear Regression

Business Statistics. Lecture 10: Correlation and Linear Regression Business Statistics Lecture 10: Correlation and Linear Regression Scatterplot A scatterplot shows the relationship between two quantitative variables measured on the same individuals. It displays the Form

More information

Basics of Experimental Design. Review of Statistics. Basic Study. Experimental Design. When an Experiment is Not Possible. Studying Relations

Basics of Experimental Design. Review of Statistics. Basic Study. Experimental Design. When an Experiment is Not Possible. Studying Relations Basics of Experimental Design Review of Statistics And Experimental Design Scientists study relation between variables In the context of experiments these variables are called independent and dependent

More information

2 Regression Analysis

2 Regression Analysis FORK 1002 Preparatory Course in Statistics: 2 Regression Analysis Genaro Sucarrat (BI) http://www.sucarrat.net/ Contents: 1 Bivariate Correlation Analysis 2 Simple Regression 3 Estimation and Fit 4 T -Test:

More information

Simple Linear Regression

Simple Linear Regression Chapter 2 Simple Linear Regression Linear Regression with One Independent Variable 2.1 Introduction In Chapter 1 we introduced the linear model as an alternative for making inferences on means of one or

More information

Chapter 10. Simple Linear Regression and Correlation

Chapter 10. Simple Linear Regression and Correlation Chapter 10. Simple Linear Regression and Correlation In the two sample problems discussed in Ch. 9, we were interested in comparing values of parameters for two distributions. Regression analysis is the

More information

Estimating σ 2. We can do simple prediction of Y and estimation of the mean of Y at any value of X.

Estimating σ 2. We can do simple prediction of Y and estimation of the mean of Y at any value of X. Estimating σ 2 We can do simple prediction of Y and estimation of the mean of Y at any value of X. To perform inferences about our regression line, we must estimate σ 2, the variance of the error term.

More information

1 A Review of Correlation and Regression

1 A Review of Correlation and Regression 1 A Review of Correlation and Regression SW, Chapter 12 Suppose we select n = 10 persons from the population of college seniors who plan to take the MCAT exam. Each takes the test, is coached, and then

More information

Regression and correlation. Correlation & Regression, I. Regression & correlation. Regression vs. correlation. Involve bivariate, paired data, X & Y

Regression and correlation. Correlation & Regression, I. Regression & correlation. Regression vs. correlation. Involve bivariate, paired data, X & Y Regression and correlation Correlation & Regression, I 9.07 4/1/004 Involve bivariate, paired data, X & Y Height & weight measured for the same individual IQ & exam scores for each individual Height of

More information

Prob/Stats Questions? /32

Prob/Stats Questions? /32 Prob/Stats 10.4 Questions? 1 /32 Prob/Stats 10.4 Homework Apply p551 Ex 10-4 p 551 7, 8, 9, 10, 12, 13, 28 2 /32 Prob/Stats 10.4 Objective Compute the equation of the least squares 3 /32 Regression A scatter

More information

Linear correlation. Contents. 1 Linear correlation. 1.1 Introduction. Anthony Tanbakuchi Department of Mathematics Pima Community College

Linear correlation. Contents. 1 Linear correlation. 1.1 Introduction. Anthony Tanbakuchi Department of Mathematics Pima Community College Introductor Statistics Lectures Linear correlation Testing two variables for a linear relationship Anthon Tanbakuchi Department of Mathematics Pima Communit College Redistribution of this material is prohibited

More information

Chapter Eight: Assessment of Relationships 1/42

Chapter Eight: Assessment of Relationships 1/42 Chapter Eight: Assessment of Relationships 1/42 8.1 Introduction 2/42 Background This chapter deals, primarily, with two topics. The Pearson product-moment correlation coefficient. The chi-square test

More information

Key Concepts. Correlation (Pearson & Spearman) & Linear Regression. Assumptions. Correlation parametric & non-para. Correlation

Key Concepts. Correlation (Pearson & Spearman) & Linear Regression. Assumptions. Correlation parametric & non-para. Correlation Correlation (Pearson & Spearman) & Linear Regression Azmi Mohd Tamil Key Concepts Correlation as a statistic Positive and Negative Bivariate Correlation Range Effects Outliers Regression & Prediction Directionality

More information

BNAD 276 Lecture 10 Simple Linear Regression Model

BNAD 276 Lecture 10 Simple Linear Regression Model 1 / 27 BNAD 276 Lecture 10 Simple Linear Regression Model Phuong Ho May 30, 2017 2 / 27 Outline 1 Introduction 2 3 / 27 Outline 1 Introduction 2 4 / 27 Simple Linear Regression Model Managerial decisions

More information

Basic Business Statistics 6 th Edition

Basic Business Statistics 6 th Edition Basic Business Statistics 6 th Edition Chapter 12 Simple Linear Regression Learning Objectives In this chapter, you learn: How to use regression analysis to predict the value of a dependent variable based

More information

AP Statistics Two-Variable Data Analysis

AP Statistics Two-Variable Data Analysis AP Statistics Two-Variable Data Analysis Key Ideas Scatterplots Lines of Best Fit The Correlation Coefficient Least Squares Regression Line Coefficient of Determination Residuals Outliers and Influential

More information

Ordinary Least Squares Regression Explained: Vartanian

Ordinary Least Squares Regression Explained: Vartanian Ordinary Least Squares Regression Explained: Vartanian When to Use Ordinary Least Squares Regression Analysis A. Variable types. When you have an interval/ratio scale dependent variable.. When your independent

More information

MATH c UNIVERSITY OF LEEDS Examination for the Module MATH1725 (May-June 2009) INTRODUCTION TO STATISTICS. Time allowed: 2 hours

MATH c UNIVERSITY OF LEEDS Examination for the Module MATH1725 (May-June 2009) INTRODUCTION TO STATISTICS. Time allowed: 2 hours 01 This question paper consists of 11 printed pages, each of which is identified by the reference. Only approved basic scientific calculators may be used. Statistical tables are provided at the end of

More information

Interactions. Interactions. Lectures 1 & 2. Linear Relationships. y = a + bx. Slope. Intercept

Interactions. Interactions. Lectures 1 & 2. Linear Relationships. y = a + bx. Slope. Intercept Interactions Lectures 1 & Regression Sometimes two variables appear related: > smoking and lung cancers > height and weight > years of education and income > engine size and gas mileage > GMAT scores and

More information

Lecture # 31. Questions of Marks 3. Question: Solution:

Lecture # 31. Questions of Marks 3. Question: Solution: Lecture # 31 Given XY = 400, X = 5, Y = 4, S = 4, S = 3, n = 15. Compute the coefficient of correlation between XX and YY. r =0.55 X Y Determine whether two variables XX and YY are correlated or uncorrelated

More information

1.5 GEOMETRIC PROPERTIES OF LINEAR FUNCTIONS

1.5 GEOMETRIC PROPERTIES OF LINEAR FUNCTIONS Functions Modeling Change: 1.5 GEOMETRIC PROPERTIES OF LINEAR FUNCTIONS Interpreting the Parameters of a Example 1 Linear Function With time, t, in years, the populations of four towns, P A, P B, P C,

More information

Simple Linear Regression

Simple Linear Regression 9-1 l Chapter 9 l Simple Linear Regression 9.1 Simple Linear Regression 9.2 Scatter Diagram 9.3 Graphical Method for Determining Regression 9.4 Least Square Method 9.5 Correlation Coefficient and Coefficient

More information

appstats27.notebook April 06, 2017

appstats27.notebook April 06, 2017 Chapter 27 Objective Students will conduct inference on regression and analyze data to write a conclusion. Inferences for Regression An Example: Body Fat and Waist Size pg 634 Our chapter example revolves

More information

9 Correlation and Regression

9 Correlation and Regression 9 Correlation and Regression SW, Chapter 12. Suppose we select n = 10 persons from the population of college seniors who plan to take the MCAT exam. Each takes the test, is coached, and then retakes the

More information

Prof. Bodrero s Guide to Derivatives of Trig Functions (Sec. 3.5) Name:

Prof. Bodrero s Guide to Derivatives of Trig Functions (Sec. 3.5) Name: Prof. Bodrero s Guide to Derivatives of Trig Functions (Sec. 3.5) Name: Objectives: Understand how the derivatives of the six basic trig functions are found. Be able to find the derivative for each of

More information

Chapter 10. Regression. Understandable Statistics Ninth Edition By Brase and Brase Prepared by Yixun Shi Bloomsburg University of Pennsylvania

Chapter 10. Regression. Understandable Statistics Ninth Edition By Brase and Brase Prepared by Yixun Shi Bloomsburg University of Pennsylvania Chapter 10 Regression Understandable Statistics Ninth Edition By Brase and Brase Prepared by Yixun Shi Bloomsburg University of Pennsylvania Scatter Diagrams A graph in which pairs of points, (x, y), are

More information

Lecture 30. DATA 8 Summer Regression Inference

Lecture 30. DATA 8 Summer Regression Inference DATA 8 Summer 2018 Lecture 30 Regression Inference Slides created by John DeNero (denero@berkeley.edu) and Ani Adhikari (adhikari@berkeley.edu) Contributions by Fahad Kamran (fhdkmrn@berkeley.edu) and

More information

Session 4 2:40 3:30. If neither the first nor second differences repeat, we need to try another

Session 4 2:40 3:30. If neither the first nor second differences repeat, we need to try another Linear Quadratics & Exponentials using Tables We can classify a table of values as belonging to a particular family of functions based on the math operations found on any calculator. First differences

More information

Correlation: Relationships between Variables

Correlation: Relationships between Variables Correlation Correlation: Relationships between Variables So far, nearly all of our discussion of inferential statistics has focused on testing for differences between group means However, researchers are

More information

Example: Can an increase in non-exercise activity (e.g. fidgeting) help people gain less weight?

Example: Can an increase in non-exercise activity (e.g. fidgeting) help people gain less weight? Example: Can an increase in non-exercise activity (e.g. fidgeting) help people gain less weight? 16 subjects overfed for 8 weeks Explanatory: change in energy use from non-exercise activity (calories)

More information

Ch Inference for Linear Regression

Ch Inference for Linear Regression Ch. 12-1 Inference for Linear Regression ACT = 6.71 + 5.17(GPA) For every increase of 1 in GPA, we predict the ACT score to increase by 5.17. population regression line β (true slope) μ y = α + βx mean

More information

Finding Relationships Among Variables

Finding Relationships Among Variables Finding Relationships Among Variables BUS 230: Business and Economic Research and Communication 1 Goals Specific goals: Re-familiarize ourselves with basic statistics ideas: sampling distributions, hypothesis

More information

Correlation and Regression

Correlation and Regression Elementary Statistics A Step by Step Approach Sixth Edition by Allan G. Bluman http://www.mhhe.com/math/stat/blumanbrief SLIDES PREPARED BY LLOYD R. JAISINGH MOREHEAD STATE UNIVERSITY MOREHEAD KY Updated

More information

Chapter 9 - Correlation and Regression

Chapter 9 - Correlation and Regression Chapter 9 - Correlation and Regression 9. Scatter diagram of percentage of LBW infants (Y) and high-risk fertility rate (X ) in Vermont Health Planning Districts. 9.3 Correlation between percentage of

More information