04/21/23 Copyright Ed Lipinski and Mesa Community College, 2003-2009. All rights reserved.

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Research MethodsSummer 2009

Choosing a Research Design

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Agenda

• General Housekeeping

• Assignments

• Lesson Objective

• Ed’s Overview / Discussion

• Questions.

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Objective

• “... to determine how to choose a research design”

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Ed’s Overview

• I. Functions of a Research Design

• II. Causal Versus Correlational

• III. Correlational Research

• IV. Experimental Research

• V. Internal and External Validity

• VI. Research Settings.

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I. Functions of a Research Design

• Focus of Research• Exploratory Data Analysis• Hypothesis Testing.

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II. Causal Versus Correlational

• A. Causal Relationship• One Variable Directly Influences

Another• Causal-Comparative Research• Preferred Methodology

• B. Correlational Relationship• Variable Changes Are Related

• C. Difference Is Degree of Control.

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III. Correlational Research

• A. Characteristics• B. Example of Such• C. Causation and Correlation

• Third Variables• Directionality

• D. Why Correlational?• Data Gathering• Inability to Manipulate• Naturally Occurring Variables.

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III. Correlational Research

• E. Simple Correlation• Relationship Between Weather and

Mood• “Measure” the Weather• Measure Mood• Calculate the Pearson r.

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III. Correlational Research

• Measuring Mood (Scale of 1 to 5)• Happy / Sad• Active / Passive• Unfriendly / Friendly• Bad / Good• Busy / Lazy• Unsatisfied / Satisfied• Kind / Cruel.

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IV. Experimental Research…

• A. Characteristics• B. Example of Such• C. Strengths and Limitations• D. Experiments Versus Demonstrations.

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IV. Experimental Research

• A. Characteristics• Independent Variable• Treatments• Dependent Variable• Experimental Group• Control Group• Extraneous Variables.

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IV. Experimental Research

• B. Example of Such• How could we carry out BBVM

Research?• Manipulation of the I.V.• Control Over Extraneous• Other Potential Confounds.

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IV. Experimental Research

• C. Strengths and Limitation• Identify Causal Relationships• Can’t Be Used w/o I.V. Manipulation• Causal – Comparative Research• Control Over Extraneous Variables.

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IV. Experimental Research

• D. Experiments Versus Demonstrations• Experiment w/o I.V.• Good To Examine Conditions• Example

• What makes this a demonstration?• What can be concluded?• How could this be an experiment?• What are potential hypotheses?.

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V. Internal Versus External Validity

• A. Internal Validity• Test What It Should• I.V. Caused the D.V.• Correlation, Not Extraneous• Confounding• Threats To Internal Validity• Enhancing Internal Validity.

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V. Internal Versus External Validity

• B. External Validity• Measure Is Consistent• Threats To External Validity

• C. One Versus The Other• Tend To Be Inversely Proportional• Which Is More Important• Large N, Good Controls.

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VI. Research Settings

• A. Laboratory Setting (Simulations)• B. Realism• C. Field Experiments.

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Recap

• I. Functions of a Research Design

• II. Causal Versus Correlational

• III. Correlational Research

• IV. Experimental Research

• V. Internal and External Validity

• VI. Research Settings.

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Choosing a Design

Questions