Research Methodology Josée L. Jarry, Ph.D., C.Psych. Introduction to Psychology Department of Psychology University of Toronto June 4, 2003

The Story of Clever Hans Horse who became famous throughout Europe for his ability to answer questions Von Osten spent 4 years tutoring Hans in reading, arithmetic, history, etc… Hans spelled out words using hoof taps Tossed his head up and down for yes, and back and forth for no Hans could answer questions in written or spoken German about geography, history, science, math, or current events He could also answer questions put to him in other languages

Clever Hans: The Mystery Eminent psychologists and zoologists examined Hans’ performance None could find any evidence of charlatanism The horse could also answer questions while the owner was not there Circus trainers could find no evidence of trickery

Clever Hans Revealed Oskar Pfungst, a psychologist, performed some simple experiments Hypothesized that Hans responded to visual signals produced by questioners or observers Found that Hans could not answer questions when he was fitted with blinders that prevented him from seeing people around him He could also not answer questions unless at least one person who knew the answer was in his sight

Facts, Theories, and Hypotheses Fact –Objective statement, based on observation, that reasonable observers agree is true Theory –Idea, or mental model designed to explain facts Hypothesis –Derived from a theory –Makes predictions, based on the theory, about new facts that might be discovered

Basic Elements of Scientific Research Skepticism –Basic approach of scientists –Consist of going beyond how facts appear to work Observation under controlled conditions –Consists of varying one variable at a time Observer-expectancy effects –Experimenter unintentionally communicates expectations to subjects

Dimensions of Research Strategy Research design –Experimental –Correlational –Descriptive Setting –Laboratory –Field Data collection method –Observation –Self-report

Research Designs

Experiments A procedure in which a researcher systematically varies one or more independent variables while looking for changes in one or more dependant variables, keeping all other variables constant Independent variable –the variable that is hypothesized to cause some effect on the dependent variable Dependant variable –the variable that is hypothesized to be affected by the independent variable

Experimental and Control Groups Experimental group –Group to which the independent variable is applied –Different levels of the independent variable are applied to different experimental groups Control group –The group to which the independent variable is not applied

Between and Within Subjects Designs Between-groups experiment –An experiment where the different levels of the independent variable are applied to different groups of subjects Within-subjects experiment –An experiment where different levels of the independent variable are applied to the same subject –Each subject is exposed to all levels of the independent variable

Correlational Studies When it is impossible to manipulate the independent variable of choice Study in which the experimenter does not manipulate any variables Observes or measures two or more variables to find relationships among them Can identify lawful relationships Cannot verify the existence of cause and effects relationships

Descriptive Studies Study in which the goal is to describe the behaviour of an individual or a set of individual No investigation of relationships between specific variables May or may not involve numbers If does, will describe percentages

Research Settings

Laboratory Studies A study in which the subjects are brought to a specially designed area that has been set up to facilitate the researcher’s ability to collect data or to control environmental conditions Advantages –Allows data collection under uniform, controlled conditions Limits –The strangeness or artificiality of the laboratory –May obscure behaviours of interest

Field Studies A study conducted in a setting other than the laboratory Advantages –More natural environment where behaviour can proceed the way it normally does Limits –Absence of control –What appears to be a cause may in fact not be –Everything varies at the same time

Data-Collection Methods

Self-Report Methods Subjects are asked to rate or describe their own behaviour or mental state Questionnaire –Subjects produce written self-descriptions Interview –Subjects describe themselves orally to an interviewer Limits –The validity of the results is limited by the subjects’ honesty and their ability to observe and remember their own behaviour or mood

Observational Methods Naturalistic observation –Minimizes interference with behaviour Advantages –Ecologically valid account of behaviour Limits –Extremely time consuming –Difficult to observe behaviour without disrupting it –Coding data in a form that can be used for later statistical analyses

Observational Methods Tests –The researcher deliberately presents stimuli or problems for the subjects to respond to Advantages –Convenient and objective Limits –Artificial –The relationship between test results and everyday behaviour is not always clear