The Research Enterprise in Psychology Chapter 2 This multimedia product and its contents are protected under copyright law. The following are prohibited by law: any public performance or display, including transmission of any image over a network; preparation of any derivative work, including the extraction, in whole or part, pf any images; any rental, lease, or lending of the program. Developed by Stephen Tracy Community College of Southern Nevada
Psychology: Science or Common Sense What qualifies a field of study as science?
What process do scientists use to answer questions about behavior and mental processes? Scientific Approach The orderly, systematic procedures that researchers follow as they: identify a research problem, design a study to investigate the problem, collect and analyze data, draw conclusions, and communicate their findings. *Most objective method known for acquiring knowledge*
Goals of Psychology Measure & Description Tells what occurred as accurately and completely as possible Understanding & Prediction Requires an understanding of conditions (why did they occur?) Confirmed by ruling in or out alternatives Explanation tells why an event or behavior occurred Met when researchers can specify the conditions under which a behavior is likely to occur Must identify all antecedent conditions Hypotheses are developed based on the understanding of conditions Application & Control Know how to apply a principle in order to prevent unwanted occurrences or bring about desired outcomes
Goals of Psychology Two types of research help psychologists accomplish the four goals: Basic Research Conducted to seek new knowledge and explore and advance general scientific understanding (i.e. motivation, emotional expression) Applied Research Conducted specifically to solve practical problems and improve the quality of life (i.e. methods to improve memory or increase motivation) Mainly focuses on Application & Control
Steps in The Scientific Method 1. Formulate a testable hypothesis 2. Design a study 3. Collect data 4. Analyze the data & draw conclusions 5. Report the findings
Advantages of the Scientific Approach Clarity & Precision Requires specification Intolerance of error
Types of Research Methods Experimental research methods Descriptive/correlational research methods
The Experimental Method Experimental Method The only research method to identify cause-effect relationships between two or more variables or conditions. It is designed to test a hypothesis. Variable Any condition or factor that can be manipulated, controlled, or measured Hypothesis A prediction about cause-effect relationship between two or more variables
The Experimental Method Independent Variables A factor or condition deliberately manipulated to determine whether it causes changes in another behavior or condition Researcher deliberately manipulates the IV Dependent Variable The factor or condition that is measured at the end of an experiment and is presumed to vary as a result of the manipulations of the IV Operational Definitions Specifying how variables in an experiment will be observed and measured
The Experimental Method Experimental group The group that is exposed to an independent variable Control group A group similar to the experimental group Exposed to the same experimental environment Not given the IV Used for comparison purposes
Descriptive Research Methods The Correlational Method Establishes the degree of relationship (correlation) between two characteristics, events, or behaviors (i.e. amount of time studying and grade point avg) Correlation Coefficient A numerical value that indicates strength and direction of the relationship between variables Ranges from +1.00 (perfect positive correlation) to.00 (no relationship) to -1.00 (a perfect negative correlation) The number represents the strength of the relationship between two variables higher the number, the stronger the relationship (i.e. -.85 is stronger than +.64) The signs + or indicates whether the two variables vary in the same direction or opposite directions.
Descriptive Research Methods Positive Correlation Two variables vary in same direction When stress increases illness usually increases Negative Correlation One value s increase associated with decrease in another Number cigarettes smokes and years expected to live
Descriptive Research Methods Correlational Studies Correlation does not prove causation Cause-effect conclusions limited Advantages Ethical reasons don t allow direct studies Researchers can t ask pregnant women to drink alcohol Variables of interest can t be manipulated Does gender cause differences in behavior? Less time consuming to conduct Correlational studies often less complex
Descriptive Research Methods Research methods that yield descriptions of behavior Naturalistic observation Researchers observe and record behavior in its natural setting without influencing or controlling it Advantage Opportunity to study behavior in normal settings; sometimes the only feasible way to study behavior Limitations Observer bias Expectations influence observations or interpretations Must wait for behaviors to occur
Descriptive Research Methods Laboratory Observation Behavior is studied in a laboratory setting, where researchers can exert more control and use more precise equipment to measure responses Limitations Laboratory behavior may not accurately reflect real world behavior Equipment can be expensive
Descriptive Research Methods The Case Study A single person or a small number of individuals are studied in great depth usually done over an extended period of time Uses observations, interviews, or psychological testing Purpose is to provide detailed description of some behavior or disorder (i.e. particularly appropriate for uncommon disorders Limitations: Causes of behavior difficult to establish Observer bias Applicability to larger groups or different cultures questionable
Descriptive Research Methods Survey Research Interviews or questionnaires are used to gather information about attitudes, beliefs, experiences, or behaviors of a group of people (i.e. drug use) Population Entire group of interest to researchers to which they wish to generalize their findings Sample Part of a population that is studied in order to reach conclusions about the entire population Representative sample Sample that mirrors the population of interest Includes subgroups in the same proportion as found in the population
Descriptive Research Methods Survey Research Interviews and Questionnaires Results can be affected by wording, content, and interviewer characteristics Questionnaires are less expensive and can gather information from large groups quickly May or may not meet scientific scrutiny Limitations Costly and time consuming Faulty information may be gathered Social desirability response Deliberately provide misleading information
Sources of Bias in Research Confounding variables Extraneous variables (time of day, type of subject, experimenter bias) Selection bias Assignments to groups so systematic differences are present Random assignment All participants have equal chance of b eing assigned to each condition Placebo effect Response to treatment is due to a person s expectations not the treatment itself Placebo An inert substance given to control group to control for placebo effect Experimenter bias Experimental results influenced by the researcher Double-blind procedure Neither researchers nor participants are aware of who is in control of experimental groups
Research Methods in Psychology Legality: research must conform to applicable laws Institutional approval: required clearance from institution/school Informed Consent: participants must be informed of the purpose and any potential harm Deception: only used when necessary and no other means available Debriefing: participants are informed of any deception after end of research Clients, patients, students, and subordinates: steps used to assure participants are not damaged in any way by participating Payment for participation: fully informed what is expected Publication: findings must be made available to others for verification Use of animals: required adherence to laws and appropriate care Minimization of discomfort: ethical duty to minimize discomfort to animals and to euthanize in humane manner when necessary