Copyright © 2005 Pearson Education Canada Inc. 1 Psychology as a Science Theory development involves collecting interrelated ideas and observations Taken together, these describe, explain, and predict behaviour
Copyright © 2005 Pearson Education Canada Inc. 2 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
Copyright © 2005 Pearson Education Canada Inc. 3 Three Principles of Scientific Endeavour A second principle is accuracy Accuracy means gathering data in precise ways
Copyright © 2005 Pearson Education Canada Inc. 4 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
Copyright © 2005 Pearson Education Canada Inc. 5 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
Copyright © 2005 Pearson Education Canada Inc. 6 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
Copyright © 2005 Pearson Education Canada Inc. 7 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
Copyright © 2005 Pearson Education Canada Inc. 8 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
Copyright © 2005 Pearson Education Canada Inc. 9 Experimental Method Operational definition is defining a variable in terms of the set of methods or procedures used to measure that variable
Copyright © 2005 Pearson Education Canada Inc. 10 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
Copyright © 2005 Pearson Education Canada Inc. 11 Experimental Method In an experiment, a significant difference is unlikely to have occurred because of chance alone
Copyright © 2005 Pearson Education Canada Inc. 12 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
Copyright © 2005 Pearson Education Canada Inc. 13 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
Copyright © 2005 Pearson Education Canada Inc. 14 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
Copyright © 2005 Pearson Education Canada Inc. 15 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
Copyright © 2005 Pearson Education Canada Inc. 16 Ethics in Research A debriefing at the end of study informs participants about the true nature of an experiment
Copyright © 2005 Pearson Education Canada Inc. 17 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
Copyright © 2005 Pearson Education Canada Inc. 18 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?
Copyright © 2005 Pearson Education Canada Inc. 19 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
Copyright © 2005 Pearson Education Canada Inc. 20 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
Copyright © 2005 Pearson Education Canada Inc. 21 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