Data Transformation Data Analysis.

Slides:



Advertisements
Similar presentations
4.1: Linearizing Data.
Advertisements

From the Carnegie Foundation math.mtsac.edu/statway/lesson_3.3.1_version1.5A.
1. What is the probability that a randomly selected person is a woman who likes P.E.? 2. Given that you select a man, what is the probability that he likes.
Statistics for the Social Sciences
Regression, Residuals, and Coefficient of Determination Section 3.2.
Residuals and Residual Plots Most likely a linear regression will not fit the data perfectly. The residual (e) for each data point is the ________________________.
VCE Further Maths Least Square Regression using the calculator.
AP STATISTICS LESSON 3 – 3 LEAST – SQUARES REGRESSION.
Correlation & Regression – Non Linear Emphasis Section 3.3.
3.2 Least Squares Regression Line. Regression Line Describes how a response variable changes as an explanatory variable changes Formula sheet: Calculator.
Regression Regression relationship = trend + scatter
Scatter Plots And Looking at scatter plots Or Bivariate Data.
3.2 - Least- Squares Regression. Where else have we seen “residuals?” Sx = data point - mean (observed - predicted) z-scores = observed - expected * note.
Transformations.  Although linear regression might produce a ‘good’ fit (high r value) to a set of data, the data set may still be non-linear. To remove.
YOU NEED TO KNOW WHAT THIS MEANS
A P STATISTICS LESSON 3 – 3 (DAY 3) A P STATISTICS LESSON 3 – 3 (DAY 3) RISIDUALS.
Introduction to Regression
Chapter 8 Linear Regression. Fat Versus Protein: An Example 30 items on the Burger King menu:
Unit 3 Test Review – Identifying Parent Functions October 30, 2014.
Chapter 10 Notes AP Statistics. Re-expressing Data We cannot use a linear model unless the relationship between the two variables is linear. If the relationship.
REGRESSION MODELS OF BEST FIT Assess the fit of a function model for bivariate (2 variables) data by plotting and analyzing residuals.
12 Further mathematics Data Transformation.
Chapter 8 Part I Answers The explanatory variable (x) is initial drop, measured in feet, and the response variable (y) is duration, measured in seconds.
12.2 TRANSFORMING TO ACHIEVE LINEARITY To use transformations involving powers, roots, and logarithms to find a power or exponential model that describes.
CHAPTER 3 Describing Relationships
Statistics 101 Chapter 3 Section 3.
CHAPTER 3 Describing Relationships
CHAPTER 3 Describing Relationships
distance prediction observed y value predicted value zero
Statistics for the Social Sciences
Section 3.2: Least Squares Regression
Unit 2 Exploring Data: Comparisons and Relationships
MATH 2311 Section 5.5.
Re-expressing the Data: Get It Straight!
Active Learning Lecture Slides
Cautions about Correlation and Regression
Residuals From the Carnegie Foundation math.mtsac.edu/statway/lesson_3.3.1_version1.5A.
(Residuals and
Bell Ringer Make a scatterplot for the following data.
Warm-Up . Math Social Studies P.E. Women Men 2 10
Day 13 Agenda: DG minutes.
1) A residual: a) is the amount of variation explained by the LSRL of y on x b) is how much an observed y-value differs from a predicted y-value c) predicts.
Investigating Relationships
Re-expressing the Data: Get It Straight!
Re-expressing the Data: Get It Straight!
Residuals Learning Target:
Describing Bivariate Relationships
Regression.
Least-Squares Regression
Linear Models and Equations
GET OUT p.161 HW!.
Warm-Up 8/50 = /20 = /50 = .36 Math Social Studies P.E.
Residuals and Residual Plots
Regression.
M248: Analyzing data Block D UNIT D2 Regression.
CALCULATING EQUATION OF LEAST SQUARES REGRESSION LINE
MATH 2311 Section 5.5.
Lecture 6 Re-expressing Data: It’s Easier Than You Think
Residuals From the Carnegie Foundation math.mtsac.edu/statway/lesson_3.3.1_version1.5A.
3.2 – Least Squares Regression
Homework: pg. 276 #5, 6 5.) A. The relationship is strong, negative, and curved. The ratios are all Since the ratios are all the same, the exponential.
A medical researcher wishes to determine how the dosage (in mg) of a drug affects the heart rate of the patient. Find the correlation coefficient & interpret.
Ch 9.
Homework: PG. 204 #30, 31 pg. 212 #35,36 30.) a. Reading scores are predicted to increase by for each one-point increase in IQ. For x=90: 45.98;
Warm-Up . Math Social Studies P.E. Women Men 2 10
Regression and Correlation of Data
Residuals From the Carnegie Foundation math.mtsac.edu/statway/lesson_3.3.1_version1.5A.
Residuals and Residual Plots
Review of Chapter 3 Examining Relationships
MATH 2311 Section 5.5.
Presentation transcript:

Data Transformation Data Analysis

Residual Analysis From: Jones et al., (2012) Essential Further Mathematics 4E, pg 132

Residual Actual y value – predicted y value = residual Actual y value comes from the scatterplot. It is from the actual data. Predicted y value comes from the equation. It is a theoretical value. When we add all of the residuals from a least squares regression they should add to zero, or very close to zero.

From: MathsQuest 12 Further Mathematics VCE Units 3 and 4 (5E) by Barnes, Nolan and Phillips, pg 145 Residual Plot Plots the residuals against the original x values. If the residuals are randomly scattered then we probably have a linear relationship. If they form a pattern, such as a curve, they probably form a non-linear relationship. Page 168 of the calculator notes explain how to do a residual plot.

From: MathsQuest 12 Further Mathematics VCE Units 3 and 4 (5E) by Barnes, Nolan and Phillips, pg 149 Transforming data If the data is non-linear we may be able to transform it and force it to be linear. See the Transforming to Linearity Interactivity in eBookPLUS.

Logarithmic and Reciprocal Transformations From: MathsQuest 12 Further Mathematics VCE Units 3 and 4 (5E) by Barnes, Nolan and Phillips, pg 150 Logarithmic and Reciprocal Transformations

Quadratic Transformations From: MathsQuest 12 Further Mathematics VCE Units 3 and 4 (5E) by Barnes, Nolan and Phillips, pg 150 Quadratic Transformations

From: Jones et al., (2012) Essential Further Mathematics 4E, pg 190

Which transformation do I choose? The best transformation will be the one with r = +/- 1. The closer to 1 (or -1) the better the transformation. You should try all transformation for the appropriate quadrant in the circle of transformations before making your choice.

If your data is non-linear you will also need to transform the data using the correct methods and choose the best model. From: Jones et al., (2012) Essential Further Mathematics 4E, pg 140