Agenda for January 25 th Administrative Items/Announcements Attendance Handouts: course enrollment, RPP instructions Course packs available for sale in 208 Porter Hall Selection of presentation week/topic Anyone with special needs: come see me Pictures on Thursday! Follow up from last week Results from in-class study Quiz example (“feedback exercise”) Begin this week’s topic: Research Methods

Follow-Up From Last Week Quiz example: 1. (a) What is the central tension between emotion theorists who take a social constructivist position vs. those who take an evolutionary position? (b) Explain one piece of evidence that supports each of these positions.

An Open Mouth Increased Perceived Humorousness of the Cartoon M closed = 2.92, M open = 3.62, F (1) = 6.61, p <.05

Scientific Method in Decision Science Basic belief that there are consistencies that can be uncovered Science as an ongoing process

Goals 1.Measurement and Description 2.Understanding and Prediction 3.Application and Control

Steps in the Scientific Investigation Step 1: Formulate a testable hypothesis Step 2: Select the research method and design the study Step 3: Collect the data Step 4: Analyze the data and draw conclusions Step 5: Report the findings

Hypothesis a tentative statement about the relationship between two or more variables

Operational Definition describes the actions that will be made to measure or control a variable

Subjects/Participants person’s or animals whose behavior is systematically observed in a study

Steps in the Scientific Investigation Step 1: Formulate a testable hypothesis Step 2: Select the research method and design the study Step 3: Collect the data Step 4: Analyze the data and draw conclusions Step 5: Report the findings

Types of Research Methods A.Descriptive Research 1.Case Studies 2.Observational Studies a. Naturalistic Observation b. Laboratory Observation 3.Surveys 4.Tests B.Correlational Studies C.Experimental Research

A. Descriptive Research allow researcher to describe and predict behavior do not show causality

1. Case Studies detailed description of a particular individual under study or treatment

2. Observational Studies researcher carefully and systematically observes and records behavior without interfering in any way with the behavior

a. Naturalistic Observation used to describe behavior as it occurs in the natural environment measure behavior in a systematic way

b. Laboratory Observation descriptive study takes place in the lab

Types of Research Methods A.Descriptive Research 1.Case Studies 2.Observational Studies a. Naturalistic Observation b. Laboratory Observation 3.Surveys 4.Tests B.Correlational Studies C.Experimental Research A.Descriptive Research 1.Case Studies 2.Observational Studies a. Naturalistic Observation b. Laboratory Observation 3.Surveys 4.Tests B.Correlational Studies C.Experimental Research

3. Surveys questionnaires and interviews that ask people directly about their experiences, attitudes, or opinions

4. Tests procedures used to measure personality traits, emotional states, aptitudes, interests, abilities, and values

Validity refers to the degree to which the content of a test is representative of the domain it is supposed to cover

Reliability whether a test yields consistent results from one time to another

B. Correlational Studies Correlation - a measure of how strongly two or more variables are related to each other Usually used when cannot control the variables to be measured

Positive Correlation High values of one variable are associated with high values of another Low values of one variable are associated with low values of another

Scatter Plot Examples Put up overhead transparency

Negative Correlation High values of one variable are associated with low values of the other variable If there is no relationship between the variables, they are uncorrelated

Correlation Coefficient Correlations are measured using the correlation coefficient (r) r ranges in value from to

Causality Correlational studies give us information about relationships, but they cannot tell us anything about causality

Types of Research Methods A. Descriptive Research B. Correlational Research Experimental Research C. Experimental Research

C. Experimental Research Used to understand causality Control situation being studied

Variables Two types of variables 1.Independent Variables 2.Dependent Variables

Independent Variable Variable that is manipulated Hold everything constant except for the independent variable

Dependent Variable Variable affected by the manipulation

Experimental and Control Groups Experimental group - group exposed to the manipulation Control group - group not exposed to the manipulation

Random Assignment Participants randomly assigned to either the experimental or control group. This avoids selection effects. Balances individual differences among participants across groups

Avoiding Bias Single-Blind Study - subjects are not told what condition they are in Double-Blind Study - person running experiment does not know which participants are in which groups during data collection. This avoids experimental demand.

Statistics Statistical analyses used to quantify strength of association between variables Involves the use of mathematics to organize, summarize, and interpret numerical data

Descriptive Statistics Used to organize and summarize data Provide an overview of numerical data Two main components: Central Tendency Variance

Central Tendency Three components to understanding the typical or average score median mean mode

Median Score that falls exactly in the center of the distribution of scores Half of the scores fall above the median and half fall below the median

Mean Arithmetic average of the scores in the distribution

Mode the most frequent score in the distribution

Variance How much the scores in the data set vary from each other and the mean Standard Deviation - index of the amount of variability in a set of data

Inferential Statistics Used to evaluate the probability that results might be due to chance

Statistical Significance Statistical significance - when low probability that observed findings are due to chance Very low usually means less than 5 chances in 100