Methods of Psychological Research What we know knowledge changes Empiricism the belief that accurate knowledge can be acquired through observation o Scientific Method a set of principles about the appropriate relationship between ideas and evidence o Theory a hypothetical explanation of a natural phenomena o Hypothesis a falsifiable prediction made by a theory The scientific method 4 main goals o Description what happens o Prediction when it happens o Causal control what causes it to happen o Explanation why it happens The empirical process depends on theories hypothesis and research o E g theory alcohol intoxication impairs driving skills Hypothesis people who are intoxicated will show less motor coordination Data Measures seconds a person can stand on one leg after drinking alcohol the data then either does or doesn t support the theory o The empirical process is systematic o Measurements are they really measuring what they think How are they gathering data E g from the venting anger study is blasting loud sounds a good way to measure anger Common research methods in psychology o Descriptive research methods observe classify o Correlational methods how variables are correlated o Experimental methods they try to determine the cause involves manipulating o ONLY experiments can prove causality b c they are able to manipulate conditions conditions behavior Descriptive research methods studies o Case studies careful description based on repeated observations Freud Sacks clinical o Naturalistic Observation a technique for gathering scientific information by unobtrusively observing people in their natural environments an outsider perspective but sometimes they manipulate the conditions and observe how the subjects respond naturally Ethnology researchers Ecological validity the environment is natural b c people behave differently in a lab setting for example E g Researchers watched who helped people in need and saw that people were the most helpful in Latin American countries E g Jane Goodall observing chimpanzees Research confederate the researcher doing the observing o Surveys Demand characteristics observer bias o Demand characteristics those aspects of an observational setting that cause people to behave as they think they should E g The Hawthorne effect researchers were testing whether the amount of light affected productivity but because the workers knew they were being watched productivity went way up at all light levels and the researchers had gained no information on their theory o Observer bias expectations can influence observations influence perceptions of reality Observational techniques o Response to a stimulus reaction time response accuracy stimulus judgments can measure bias we are unaware of because the subjects must respond immediately there are no demand characteristics E g implicit association test measures biases prejudices we are unaware of e g women are associated with family men with careers b c when asked to sort words into categories of women career or men family the reaction times were slower than sorting them into women family or men career o Stroop test names of colors are written out in colored type In the first few lines the colors match the words yet in the last few they do not People are asked to name the color each word is and generally people respond slower to the last lines because the written words distract us from naming the contrasting colors o PET scans show us where the blood flows in the brain and therefore where brain activity is o MRIs not used much in psychology show the structure of the brain o FMRIs allows us to look at the brain in an active state and see what parts light up with certain tasks We can compare people s emotions e g psychopaths vs others psychopaths tend to have deficits in emotional processes communication between different parts of the brain Diallo case o The police believed they saw a man who was a rapist they were looking for told him to freeze however he was actually a recent immigrant and couldn t understand them As he reached into his pocket the police thought he was reaching for a gun and shot o There was an implicit association between white men tools and black men guns him shown in a study o Research suggests we can work to undo these biases with training Main issue with scientific method implementing research o How to measure o Who to sample o How to avoid measurement bias o How to avoid sampling bias Managing measurement bias o 2 important types are Sampling bias having a problematic sample not random enough E g Oprah magazine surveys women on extramarital affairs but not all women read Oprah magazine or fill out the survey so it is a poor sample E g testing drugs only on males when intended for both genders or only on adults when intended for children E g many college students participate in research studies but they may not be representative of the population more intelligent regular food housing etc Expectancy bias expectations influence the results e g the Hawthorne effect Minimizing sampling bias o Random sampling everyone has an equal chance of being in the study o Representative populations the sample and the population are similar When generalizing applying the results of a study to the population one must make sure that the sample is representative of the population E g UW Madison students participating in studies are not a random sample and probably not representative of the population because we are a convenience sample subjects are used because they are convenient Expectancy bias 2 forms observation o Observer experimenter expectancies they expect a certain outcome which skews their o Subject research respondent expectancies they attempt to understand what the research is about which skews their response o E g when telling one group of observers they have smart genetically modified rats and another group that they have normal rats the former group will actually think observe that their rats are faster Controlling Expectancy bias Research methodology continued o E g Anger venting experiment objectively measured etc o Blindness blind experimenters blind subjects or double blind both when not much is known about the experiment its purposes to prevent expectancy bias o Biases were controlled all the essays feedback were the same their aggression was o This supports their causal conclusion because venting was the ONLY variable Variable a property whose value can vary across individuals or over time