Presentation on theme: "Chapter 1 Psychology as a Science"— Presentation transcript:
1 Chapter 1 Psychology as a Science Research Methods
2 Scientific Methods- are a set of procedures used to gather, analyze, and interpret information.- their purpose is to minimize error and Lead to dependable generalizations.
3 Critical Thinking - is the process of: deciding what to believe and how to actbased on a careful evaluation of the evidenceand ruling out alternative explanations.
4 What makes a good theory? 1. Predictive accuracy—Can the theory reliably predict behavior?2. Internal coherence—Are there logical inconsistencies between the theoretical ideas?
5 What makes a good theory? 3. Being economical—Does the theory include only what is necessary to explain the phenomenon in question?4. Fertility—Does the theory generate research, and can it be used to explain a wide variety of behavior?
6 Research: Three basic techniques of data collection Three basic techniques of data collection are:self-reports (interviews, surveys, tests)direct observationsarchival information (records)
8 Observational Research Case study: in-depth analysis of a single subjectNaturalistic observation: investigating behavior in its natural environmentLaboratory observation
9 Advantages of Observational Research Researchers can:Watch behavior in its “wholeness,” providing the full context in which to understand it.Record rare events that may never occur in a controlled laboratory environment.Systematically record events previously observed only by nonscientists.Observe events that would be too risky, dangerous, or unethical to create in the laboratory.One advantage of case study research is that it involves in-depth analysis of a single subject.Is the last line of text supposed to be bulleted?
10 Problems of Observational Research Observation of events can alter the participants’ behavior and taint the dataEthical problems involving invasion of others’ privacyOne problem with case study research is that researchers must be extremely cautious when generalizing from a single case to the entire population.Says three but there are four bullets.
11 Survey ResearchA survey is a structured set of questions or statements to measure people’s attitudes, beliefs, values, or behavioral tendencies.
12 Survey ResearchQuestions that are too vague, misdirected or biased will not yield the intended information.Questions asked to people who do not represent the population of interest will yield biased or incorrect results.
13 Survey Sampling Shere Hite Sampled 100,000 people received 4500 returnsreported that 70 % of women were having affairs(Other surveys found only 1/7)
14 The Scientific Method Correlation Coefficient a statistical measure that indicates the extent to which two factors vary together and thus how well either factor predicts the other
15 The Scientific Method Correlation Coefficient Ranges from +1 to -1 (0=no relationship)Shows strength & direction of relationshipCan be used to predict one variable from another
16 The Scientific MethodCorrelation Coefficient cannot be used as evidence of causality!!A caused B ?B caused A ?C caused both ?
17 Correlation and Causation Three possible cause-effect relationscould cause(1)Low self-esteemDepression(2)(3)Distressing eventsor biologicalpredispositioncould causeorand
18 Correlational Research The variables in correlational research are not controlled by the researcher.However, the measures yield numbers that can be analyzed using correlational statistics.
25 Correlation and Causation Three possible cause-effect relationscould cause(1)Low self-esteemDepression(2)(3)Distressing eventsor biologicalpredispositioncould causeorand
26 Experimental Variables Independent variable: the manipulated variable tested as the possible cause of changes in the other variableDependent variable: the variable whose measured differences or changes are considered to be the effect of the manipulated changes in the independent variable
27 All other important variables are controlled. Experimental Research: Determination of Cause-Effect Relationships through manipulation & controlExperimenters manipulate one variable (independent)by exposing participants to contrasting levels, and then observe the effect on another variable (dependent)not manipulated.All other important variables are controlled.
29 The Experiment Independent Variable Dependent Variable manipulated (different in each group)cause of the change in the dependent variableDependent Variablemeasured effectmay change in response to manipulations of the independent variable
30 Experimental Manipulation Experimental Conditionexposes participants to the treatment version of the independent variableControl ConditionExposes participants to no treatment or a placebo version of the independent variableserves as a comparison for evaluating the effect of the treatment
31 Random Assignmentassigning participants to experimental and control conditions by chancePurpose: to minimize the influence of preexisting differences on the different groups
32 Placebo Controls Placebo Placebo Effect A treatment that looks like the real one, but lacking the active agentPlacebo Effectany effect on behavior caused by a placebo, usually those caused from believing one has experienced genuine treatment
33 Double-blind Procedure an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebocommonly used in drug-evaluation studies
34 Comparing Research Methods Research Method Basic Purpose How Conducted What isManipulatedDescriptive To observe and Case studies, surveys, Nothingrecord behavior and naturalisticobservationsCorrelational To detect naturally Computing statistical Nothingoccurring relationships; association, sometimesto assess how well among surveyone variable predicts responsesExperimental To explore cause Manipulating one or Independentand effect more factors and using variable(s)random assignmentto eliminate preexistingdifferences amongsubjects
35 The Scientific Method Replication repeating the essence of a research study to see whether the basic finding generalizes to other participants and circumstancesusually with different subjects in different situations (by different researchers)