Psychology's Scientific Method

Objectives

5 Basic steps in the scientific research

Types of research & research settings

Analyze & interpreting data Conducting and evaluating

research--ethics in research

Psychology’s Scientific Method

Scientific Approachan organized way of using experience and testing ideas to increase knowledge:

1.Curious2.Skeptical3.Objective4.Think critically

Begins with theory…

Research settings & types of research

A theory is a broad idea or set of closely related facts that attempts to explain and predict something.

Steps of the Scientific Method

Psychology’s Scientific Method

5 steps of scientific method1. Observe phenomena2. Formulate question, hypothesis, &

prediction3. Test prediction with research4. Draw conclusions5. Evaluate & collaborate

Research settings & types of research

Types of research: Descriptive Correlational Experimental

Research settings Laboratory Natural observation

Research settings & types of research

Descriptive research: Observation Surveys & Interviews Standardized tests Case studies

Research settings & types of research

Correlational research:correlation formula Systematic observation of variables

within a sample of people Concerned with how variable change

together Correlation coefficient

Positive (r=.68) Negative (r=-.77)

Research settings & types of research

Experimental Research: IV & DV

independent variable

(the possible cause)

dependent variable

(the outcome measured)

Research settings & types of research

Caution about experimental research Validity Experimenter bias Participant bias Placebo effect

Validity

The extent to which an experiment is measuring what you intend to measure. Depression & anxiety Aggression & Fear

The soundness of the conclusions

Experimenter Bias

The influence of the experimenters own expectations on the outcome of the research.

Participant Bias

The influence of the participant’s expectations on their behavior in the experiment.

Placebo Effect

A placebo is a bogus treatment that has the appearance of being genuine.

A placebo effect occurs when subjects who have not received the independent variable have results similar to subjects who do.

Single Blind Study

Well-designed experiments control for the effects of expectations by creating conditions under which participants are unaware of the treatment and are called single blind studies.

Double Blind Study

Studies in which both participants and experimenters are unaware of who has obtained the treatment are called double-blind studies.

Analyzing and Interpreting Data

Descriptive statistics – describe and summarize data for large groups of participants

Mean: average

Median: midpoint in rank-ordered data

Mode: score appearing most often

Analyzing and Interpreting Data Measure of dispersion:

Range

Normal distribution: bell-shaped curve

Standard deviation: degree to which scores in ordered

distribution are spread out

Analyzing and Interpreting Data

Inferential statistics: methods used to indicate whether or not data sufficiently support hypothesis.

Statistical significance .05, .01, .001

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ModeMean & Median

Analyzing and Interpreting Data

Reaching conclusions from data

Statistical significance

Size of correlation

Difference of means are greater than chance

Two issues for significance

Larger sample size is better

Statistical difference does not equal practical significance

Challenges of Conducting Ethical Research

Ethics of Research with Human Participants

Ethics of Research with Nonhuman Animals

Ethics of Research with Human Participants

1. Freedom from Coercion

2. Informed consent

3. Limited deception

4. Adequate debriefing

5. Confidentiality

Ethics of Research with Nonhuman Animals

1. Necessity

2. Health

3. Humane treatment

Becoming a consumer of Psychological Research Distinguish between group results and

Individual needs Avoid overgeneralization Look beyond a single study Avoid making causal attributions Consider the source of information