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Psychology as a Science

Theory development involves collecting interrelated ideas and observations

Taken together, these describe, explain, and predict behaviour

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Three Principles of Scientific Endeavour

One principle followed by scientists in trying to be empirical is objectivity

Being objective means not being biased or using preconceived notions

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Three Principles of Scientific Endeavour

A second principle is accuracy Accuracy means gathering data in

precise ways

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Three Principles of Scientific Endeavour

The third principle is healthy skepticism Healthy skepticism means taking a

cautious view of data, hypotheses, and theories

Principle of Convergence

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Scientific Method in Psychology

Scientists develop theories through the scientific method

The first step is to state the problem The second step is to develop a

hypothesis

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Scientific Method

Step three is to design a study The fourth step is that data must be collected and analyzed The fifth step is replicating the results The sixth step is drawing conclusions and reporting results

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Experimental Method

Psychological research often takes the form of an experiment

The independent variable is manipulated by the experimenter

The second type of variable is the dependent variable

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Experimental Method

The experimental group “receives” the independent variable

The control group is a comparison group Participants are randomly divided into two

groups by random assignment

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Experimental Method

Operational definition is defining a variable in terms of the set of methods or procedures used to measure that variable

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Experimental Method

The sample is a group of participants representative of the population

The population is the entire group you might be interested in studying

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Experimental Method

In an experiment, a significant difference is unlikely to have occurred because of chance alone

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Avoiding Pitfalls

Expectations may influence researchers’ findings

A self-fulfilling prophecy is the unwitting creation by a researcher of a situation that leads to the predicted results

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Avoiding Pitfalls

A placebo treatment has no effect but is presented as possibly producing certain effects

In a double-blind technique, neither the experimenter nor the participants know who is in the control group or experimental group

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Avoiding Pitfalls

Demand characteristics are elements of a situation that may tip off a participant as to the purpose of the study

The Hawthorne effect is the finding that people behave differently when they know they are being observed

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Ethics in Research

Ethics are the rules concerning proper and acceptable conduct that investigators use to guide their research

One rule states human participants must give the research their informed consent before a study

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Ethics in Research

A debriefing at the end of study informs participants about the true nature of an experiment

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Avoiding Pitfalls

Two events are correlated when the increased presence or decreased presence of one is associated with the presence of another

Correlation coefficients are statistical values that can be calculated to determine the degree of the relationship between these variables

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Thinking Critically About Research

What is the purpose of the research? Is the methodology appropriate? Was the sample of participants

chosen properly? Are the results repeatable? How logical are the conclusions

suggested by the study?

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Methods for Gathering Data

A questionnaire is a printed form given to a large group of people

An interview is typically a face-to-face meeting in which a researcher asks standardized questions

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Methods for Gathering Data

Naturalistic observation is observation of events from a distance

Case study is a method of interviewing participants to gain information about their background

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Avoiding Bias in Research

Ethnicity is culture-, religion- or language-based

Culture is an unwritten guidebook that one uses to interpret the world

Gender, age and disabilities shape research in distinctive ways