Psych 107 Chap 2 Notes 07 06 2012 Chapter 2 Methods of Psychological Research Dr Hull Understand how research is done The Scientific Method o Perceive the question o Form a hypothesis specific statement of expectation for a relationship between two variables that is derived from theory anything that can change and be measured variable o Test the hypothesis using accepted research methods o Draw conclusions use statistical measures to organize and interpret data o Report your results clearly other scientists must be able to replicate your results if replicated then your results are reliable things can be reliable but not valid Study of men are smarter then women because of bigger head size Descriptive Studies o describe observations about behavior o case studies surveys naturalistic observation generate testable hypotheses empirical testable Types of Descriptive Methods 1 Naturalistic observation Record behavior in naturally occurring situations Major Advantage o Realistic picture of behavior Disadvantages o Observer effect observation can affect behavior Confederate hired by observer to fit in with lab and observe Participant observation observer acts as group participant same as above o Observer bias observers tend to see what they expect to see Blind observers observers do not know what the research question is o naturalistic settings may not generalize 2 Laboratory observation Advantages o Control over variables environment subjects Different from manipulation of variables o Allows use of specialized equipment o Artificial situation may result in artificial behavior Disadvantage 3 Case study study of one individual Advantage tested Disadvantage o tremendous amount of detail patterns may be detected o cannot generalize Famous case study Phineas Gage Got stabbed through head lived Ruined frontal lobe and completely changed his personality So they could change snip adjust part of frontal lob to change personalities lobalites Ex TMS artificial brain damage to research damaged brains 4 Survey Ask people collect self reported attitudes or behaviors of people Uses a random sample of people Random assignment everyone has an equal chance of being chosen Usually anonymous Representative sample randomly selected sample of subjects from Population the entire group of people or animals in which the the population researcher is interested Controls for confounding extraneous interfering something you o So white English speaking males ex confounds within that ex don t expect is sex race Advantages manipulate Disadvantages o Allows study of variables that are impossible or unethical to o Efficient looks at lots of data from lots of people o Have to ensure representative sample or results are not meaningful More people better representation o People are not always truthful courtesy bias Person wont admit to doing a drug on survey 30 for experiment 100 for descriptive Finding Relationships within descriptive data Relating descriptive variables Correlation a measure of the relationship between two variables Correlation application o knowing the value of one variable allows us to predict the value of the other variable Ex So much education so much income o r 87 means the predictions are strong r 17 means not near as strong prediction o r is the strength of the prediction positive correlation variables related in same direction ex As education years increase so does income negative correlation variables related in opposite direction ex The less cigarettes you smoke the healthier your lungs are Children who watch violent TV are more likely to display violent behavior No cause effect A significant study outcome that the outcome were not a result of chance Catch phrases more or less likely also tend to The Experiment o Randomly assign a representative sample to watch violent TV experimental condition OR o To sit still in front of a snowy TV screen control condition o Observe interpersonal behavior afterwards o Independent variable o Dependent variable The Experiment o Experiment a deliberate manipulation of a variable to see if corresponding changes in behavior result allowing the determination of cause and effect relationships Independent variable IV variable that is manipulated by the experimenter Weather they watch violent tv or not Dependent variable DV variable that represents the measurable response or behavior of the subjects in the experiment Operational definition definition of a variable that allows it to be precisely measured and that is replicable o Experimental group subjects in an experiment who are subjected to the independent variable E g watching violent TV o Control group subjects in an experiment who are not subjected to the independent variable and who may receive a placebo treatment E g watching non violent TV o Random assignment process of assigning subjects to the experimental or control groups randomly so that each subject has an equal chance of being in either group o Controls for confounding extraneous interfering variables o Advantages Allows determination of cause effect relationships hence prediction and control o Disadvantages Placebo effect the phenomenon in which the expectations of the participants in a study can influence their behavior Single blind study subjects do not know if they are in the experimental or the control group reduces placebo effect Experimenter effect tendency of the experimenter s expectations for a study to unintentionally influence the results of the study observer effect Double blind study neither the experimenter nor the subjects knows if the subjects are in the experimental or control group reduces placebo effect and experimenter effect Ethics in Psychological Research o Animal research answers questions we could never do with o Focus is on avoiding exposing them to unnecessary pain or o Animals are used in approximately 7 of psychological human research suffering studies o Correlation does not prove causation 07 06 2012 Science must combine logic with research and experimentation A cumulative process rather then a fixed product Attitude critical thinking Eric OPTIC o Observe o Predict o Test test test o Interpret Communicate