Probabilistic Equivalence in Experimental Design

Slides:



Advertisements
Similar presentations
McGraw-Hill/Irwin © 2003 The McGraw-Hill Companies, Inc.,All Rights Reserved. Part Three SOURCES AND COLLECTION OF DATA.
Advertisements

CHAPTER 8 EXPERIMENTAL DESIGN.
Pre-Experimental Designs
Experimental Designs Dr. Farzin Madjidi Pepperdine University
Experimental Design True Experimental Designs n Random assignment n Two comparison groups n Controls threats to internal validity n Strongest evidence.
8.2 PRE-EXPERIMENTAL DESIGNS (NONDESIGNS) One-Shot Case Study X O One-Group Pretest-Posttest Design O 1 X O 2 Intact-Group Comparison X O 1 ─ ─ ─ O 2.
BHV 390 Experiments. Pros about Experiments Experimental research is the best explanatory design. It is the best design to test causal relationships Experiments.
Randomized Experimental Design
Experimental Design 1
The Science of Psychology The Scientific Method and Research Design.
Experimental Designs.
CHAPTER 8 EXPERIMENTAL DESIGN.
Who are the participants? Creating a Quality Sample 47:269: Research Methods I Dr. Leonard March 22, 2010.
TRAINING EVALUATION. STEPS TO EFFECTIVE TRAINING 1.Assess Needs 2.Design Training 3.Conduct/Deliver Training 4.Ensure Transfer –Support –Consequences.
What Works? Programme Evaluations. Approaches to Delinquency Prevention and Control Predelinquent Intervention –Individual Treatment –Area Projects Preadjudication.
Relationships Among Pre-Post Designs. Pre-Post Designs l Randomized experiment (R) l Nonequivalent group design (N) l Regression-Discontinuity design.
Introduction to Research Design. What Is Research Design? The structure of research.
Experimental Designs.
MATH 310, FALL 2003 (Combinatorial Problem Solving) Lecture 20, Monday, October 20.
(a) (b) (c) (d). What is (1,2,3)  (3,4,2)? (a) (1, 2, 3, 4) (b) (1,2)  (3,4) (c) (1,3,4,2) (d) (3,1)  (4,2)
McGraw-Hill © 2006 The McGraw-Hill Companies, Inc. All rights reserved. Experimental Research Chapter Thirteen.
Experimental Research
Problem identification Research questions Constructs & Variables Research design.
3.2 Solving Inequalities by Adding or Subtracting I can solve inequalities by adding or subtracting.
I want to test a wound treatment or educational program but I have no funding or resources, How do I do it? Implementing & evaluating wound research conducted.
Statistics Ch.1: Variables & Measurement. Types Statistics: –Descriptive –Inferential Data: Collections of observations –Population –Sample.
Research Strategies, Part 2
Section 5.2 Designing Experiments AP Statistics
Name _____________________________ Draw a picture for each spelling word. Write the spelling word under each picture.
Experimental Design Presented By: Amber Atwater & Charlott Livingston.
Descriptive Observational Survey Cross-Sectional (Polls)Longitudinal Panel Trend Cohort Casual Comparative Types of Research EDF 6481 Edwin Benitez Jr.
Experimental Designs. Experiments are conducted to identify how independent variables influence some change in a dependent variable.
Training Evaluation- Design Issues Basic Designs –Post-test only –Pre-rest/Post-test Complex Designs –Post-test with control group –Pre-test/Post-test.
Experimental Research
Learning Objectives In this chapter you will learn about the elements of the research process some basic research designs program evaluation the justification.
Copyright © 2011 by The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill/Irwin Using Specialized Research Designs.
 Example 1: -2(3)  If there is only one negative it will be a negative answer.  -2(3) = -6.
Data Collection and Experimental Design. Data Collection Methods 1. Observational study 2. Experiment 3. Simulation 4. Survey.
Types of Experimental Designs (Educational research) True Experimental Quasi-Experimental.
Chapter 5.2 Designing experiments. Terminology The individuals on which the experiment is done are the experiment units. When the units are human beings.
Research Design Vocabulary
Goals of research Exploratory: new topic Descriptive: gathering information Explanatory: explain patterns, answer why Evaluation: assess outcomes Types.
Table of Contents  Research Design  Threats to Internal Validity  Threats to External Validity  Proposed Data  Pre-Test Post-Test Data Results 
Research designs Research designs Quantitative Research Designs.
Pretest Question: Three identical metal balls L, M and N initially have charge 4 C, -2 C and 0 C, respectively, as shown below. What is the charge on.
Practical Research: Planning and Design, Ninth Edition Paul D. Leedy and Jeanne Ellis Ormrod © 2010 Pearson Education, Inc. All rights reserved. 1 Chapter.
Internal Validity Questions
Experiments Why would a double-blind experiment be used?
METHODS IN BEHAVIORAL RESEARCH
Prime Time Investigation 4 Review
Design of Experiments.
Types of Designs.
Part Three SOURCES AND COLLECTION OF DATA
ASSIGNMENT NO.-2.
KINDS OF EXPERIMENT Laboratory experiments (controlled, artificial conditions): Pretest-post-test control and experimental group Two control groups and.
Making Causal Inferences and Ruling out Rival Explanations
Cube and its properties
بسم الله الرحمن الرحیم.
Quantitative Research
Pre-post Double Blind Placebo Control Group Design
Odds of Having Cancer.
9 Experimental Design.
P-VALUE.
Types of Designs: R: Random Assignment of subjects to groups
CHAPTER 8 EXPERIMENTAL DESIGN © 2012 The McGraw-Hill Companies, Inc.
Principles of Experimental Design
Introduction to Producing Data
Reminder for next week CUELT Conference.
Design of Experiments.
Principles of Experimental Design
Presentation transcript:

Probabilistic Equivalence in Experimental Design

What Is Probabilistic Equivalence? It means that we know perfectly the odds that we will find a pretest difference between the two groups. It doesn’t mean that the two groups will have identical pretest means.

What Is Probabilistic Equivalence? Group 1 49

What Is Probabilistic Equivalence? Group 1 Group 2 51 49

What Is Probabilistic Equivalence? Group 1 Group 2 51 49 With  = .05, we expect that we will observe a pretest difference 5 times out of 100.

What Is Probabilistic Equivalence? Even if we observe a pretest difference, it must be due to chance because we assigned by chance (so it’s one of the 5 out of 100 cases).

What Is Probabilistic Equivalence? If we observe a pretest difference, what does this mean for the posttest? NOTHING! The odds we will observe a posttest difference by chance are still 5 out of a 100 (with =.05).

What Is Probabilistic Equivalence? Because we assigned randomly, we could observe differences on either the pretest or posttest, but these must be due to chance (or the luck of the draw). We know perfectly the odds of observing a chance difference. We can control this (through ).