Psychology 202Chapter 2: Research MethodologyMonday, January 14, yPsychology 202Chapter 2: Research Methodology What Is Scientific Inquiry?-We will come to understand how psychologists study behavior and mental processes: describing what happens, predicting when it happens, controlling what causes it to happen, and explaining why it happens-This is known as the scientific inquiry-Scientific method: Reflects a cyclical relationship: Theory, hypothesis, conducts re-search to test the hypothesis, may reevaluate theory depending on results tom re-search. A good theory evolves over time and the result is an increasingly accurate model of some observable thingThe Scientific Method Depends on Theories, Hypothesis, and Research-The scientific method reflects dynamic interaction between three essential elements: theories, hypotheses, and research-Theory: A model of interconnected ideas or concepts that explains what is observed and makes predictions about future events• Explanation of how a phenomenon works-Hypothesis: A specific prediction of what should be observed if a theory is correct• If the theory is accurate, the prediction framed in the hypothesis should be sup-ported-Research: A scientific process that involves the systematic and careful collection of date1Monday, January 14, y-Data: Objective observations or measurements-Replication: Repetition of an experiment to confirm the results Theories Should Generate Hypotheses-A good theory provides a wide variety of testable hypothesesUnexpected Findings Can Be Valuable-Many significant findings are the result of serendipity-Serendipity: Unexpectedly discovering something important-Scientists can make mistakes when doing their research, but it can turn into following up on their unexpected findingsWhat Types of Studies Are Used in Psychological Research?-Once a scientist has come up with their hypothesis, they must decide what study of design they are going to use-There are three main types of designs: descriptive, correlation, and experimental-Variable: Something in the world that can vary and that a researcher can measure-The term can refer to something that the researcher can manipulate, something the researcher can measure, or both-Must define variables precisely and in ways that reflect the method used — opera-tional definition -Operational definition: Identifying variables and quantifying them so they can me measured-Meaning that each variable is specified in a way that makes it possible to record its quantity2Monday, January 14, yDescriptive Studies Involve Observing and Classifying Behavior-Descriptive studies: Sometimes called observational studies — A research method that involves observing and noting the behavior of people or other animals to provide a systematic and objective analysis of the behavior-There are two basic types of descriptive studies: Naturalistic observation or partici-pant observation-Naturalistic observation: A type of descriptive study in which the researcher is a passive observer, making no attempt to change or alter ongoing behavior-Participant observation: A type of descriptive study in which the researcher is ac-tively involved in the situation-Descriptive techniques are especially valuable in early stages of research-Sometimes researchers want to watch changes unfold naturally-Longitudinal studies: A research method that studies the same participants multiple times over a period of time-Research designs of this type, comparing different groups to make inferences about both are known as cross-sectional studies-Cross-sectional studies: A research method that compares participants in different groups at the same time-Longitudinal studies are expensive, they take a long time, and can be jeopardized when some participants drop out of the experiment-Cross-sectional studies are faster and less expensive, but they include the possibility that they may have a unidentifiable variable which may be responsible for any differ-ence between the groups3Monday, January 14, yObserver Bias-Observer Bias: Systematic errors in observation that occur because of an observer’sexpectations-Can especially be a problem is cultural norms favor inhibiting or expressing certain behaviors-Experimenter expectancy effect: Actual chance in the behavior of the people or nonhuman animals being observed that is due to the expectations of the observerCorrelation Studies Examine How Variables Are Related-Correlation studies: A research method that examines how variables are naturally related in the real world, without any attempt by the researcher to alter them or assign causation between them-A few potential problems prevent researchers from drawing casual conclusions from correlation studies-Directionality problem: A problem encountered in correlation studies; the re-searchers find a relationship between two variables, but they cannot determine which variable may have caused changes in the other variables.• Example — Does less sleep cause more stress does does more stress cause less sleep?-Third Variable Problem: A problem that occurs when the researcher cannot directly manipulate variables; as a result, the researcher cannot be confident that another, un-measured variable is not the actual cause of differences in the variables of interest• Driving before driving is correlated with being distracted while driving• Stress causes some people to drink before driving• Stress causes some people to be distracted while driving4Monday, January 14, y-Sometimes the third variable is obvious-People sometimes mistake a casual relationship between two variables when there is a correlationMaking Predictions-Correlation studies can be used to determine that two variables are associated with each other-By providing important information about the natural relationships between variables, researchers are able to make valuable predictions-Once researchers have shown that a relationship between two variables holds even when potential third variables are taken into account, researchers can be more confi-dent that the relationship is meaningfulAn Experiment Involves Manipulating Conditions-Experiment: A study that tests casual hypotheses by measuring and manipulating -Control group: A comparison group; the participants in a study that receive no inter-vention or receive an intervention hat is unrelated to the independent variable being investigated-Experimental groups: Treatment groups; the participants in a study that receive the