Myers PSYCHOLOGY 8 th Edition in Modules Module 2/3 Research Strategies: How Psychologists Ask and Answer Questions 1
The Need for Psychological Science Psychologists, like all scientists, use the scientific method to construct theories that organize observations and imply testable hypotheses 2
Be curious! 1. Does involvement in HS athletics improve academic performance? 2. Does excessive texting impede face-to-face relationships? 3. Does personality influence musical preferences? 4. Do ads portraying unrealistic body types reduce the self-image of the viewer? 5. Does student consumption of caffeine in the morning improve first period grades? 6. Does gamification of the classroom improve/increase student engagement? 3
Be curious! 7. Does a community service requirement positively or negatively impact student opinions of community service? 8. Does HR increase communication in a large suburban HS? 9. Do teacher websites improve student performance in class? 10. Does focus on minor rules (phones and hats) reduce student adherence to major rules (insubordination or class cutting)? 4
The Need for Psychological Science Hindsight Bias we tend to believe, after learning an outcome, that we would have foreseen it the I-knew-it-all-along phenomenon Overconfidence we tend to think we know more than we do 5
The Need for Psychological Science Theory an explanation using an integrated set of principles that organizes, explains and predicts observations Hypothesis a testable prediction often implied by a theory 6
The Need for Psychological Science 7
The Need for Psychological Science Replication repeating the essence of a research study to see whether the basic finding extends to other participants and circumstances usually with different participants in different situations 8
The Need for Psychological Science Operational Definition a statement of procedures (operations) used to define research variables Example: intelligence may be operationally defined as a score on the Stanford-Binet Test 9
Operational Definition 10
Description Psychologists describe behavior using case studies, surveys, and naturalistic observation 11
Description Case Study observation technique in which one person is studied in depth in the hope of revealing universal principals Is language uniquely human? 12
Case Study One drawback is that the individual being studied could be atypical and not reflect the "normal" population. E.g. an intensive case study on one particular child who has autism may reveal some general characteristics that might apply to a few or many autistic children. 13
Description Survey technique for ascertaining the self-reported attitudes or behaviors of people usually by questioning a representative, random sample of people False Consensus Effect tendency to overestimate the extent to which others share our beliefs and behaviors 14
Survey Research method to get the selfreported attitudes/ behaviours of people. Surveys are used in descriptive and correlational studies and tend to look at cases in less depth. 15
Survey Subject to "Wording effects : the researcher must be careful as to how the question is asked; some words may seem to have only a subtle difference in their meaning but may drastically alter a person s response to the question. 16
Wording effects In one survey 27% of respondents approved of government censorship of media sex and violence, though 66% approved of more restrictions on what is shown on TV. Aid to the needy vs welfare Revenue enhancers vs taxes Misspeaking vs lying 17
Survey Population all the cases in a group, from which samples may be drawn for a study Random Sample a sample that fairly represents a population because each member has an equal chance of inclusion 18
Survey Sampling technique is crucial to a good survey. Population: All individuals that we are interested in drawing a conclusion about Random sampling Representative sample: Reflects important aspects of the population 19
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Naturalistic Observation Naturalistic Observation observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation 21
Naturalistic Observation Observation of behavior in a natural setting Advantage: Provides a rich description of behavior Disadvantage: Does not permit clear causal conclusions Jane Goodall s research on gorillas in their natural habitat. Again, this type of study does not explain behavior 22
Correlation When finding a trait that accompanies another, we describe this as a correlation: the way 2 factors vary together and how well one predicts the other. 23
Correlation Measure associations between naturally occurring events or variables X monetary wealth Y happiness 24
Correlation Correlation Coefficient a statistical measure of the extent to which two factors vary together, and thus how well either factor predicts the other Indicates direction of relationship (positive or negative) Correlation coefficient r = +.37 Indicates strength of relationship (0.00 to 1.00) 25
Correlation Positive correlations Indicate a direct relationship where factors increase or decrease together. E.g. There is a positive correlation between the amount of television violence that a child watches and the amount of aggressive activity that they display (as one increases, the other increases); A marked decrease in the amount of sleep one gets per night is positively correlated with decreased alertness and a decrease in their ability to perform on moderately difficult tasks (as one decreases, the other decreases). 26
College GPA Correlation Positive Correlation: Higher scores on one variable are associated with higher scores on the other variable Range from +.01 to +1.00 5 4 3 2 1 0 Relationship Between H.S. GPA and College GPA 0 2 4 6 H.S. GPA 27
Correlation Negative correlations Indicate an inverse relationship where one factor goes up while one goes down. E.g. Increase the dosage of a certain painkiller and there is a decrease in pain symptoms. 28
Likelihood of Quitting Correlation Negative Correlation Higher scores on one variable are associated with lower scores on a second variable Range from -.01 to - 1.00 8 7 6 5 4 3 2 1 0 Relationship Between Job Satisfaction and Likelihood of Quitting the Job 0 2 4 6 8 Job Satisfaction 29
Correlation Scatterplot a graphed cluster of dots, each of which represents the values of two variables the slope of the points suggests the direction of the relationship the amount of scatter suggests the strength of the correlation little scatter indicates high correlation also called a scattergram or scatter diagram 30
Correlation Perfect positive correlation (+1.00) No relationship (0.00) Perfect negative correlation (-1.00) Scatterplots, showing patterns of correlations 31
32 Correlation Height and Temperament of 20 Men 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 80 63 61 79 74 69 62 75 77 60 64 76 71 66 73 70 63 71 68 70 75 66 60 90 60 42 42 60 81 39 48 69 72 57 63 75 30 57 84 39 Subject Height in Inches Temperament Subject Height in Inches Temperament
Correlation Temperament scores 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 55 60 65 70 75 80 85 Height in inches Scatterplot of Height and Temperament 33
Correlation NOTE: Correlation does not explain cause; it simply shows a relationship (or not) between factors. In order to isolate the cause we must carry out controlled experiments. 34
Correlation Three Possible Cause-Effect Relationships (1) Low self-esteem could cause or Depression (2) Depression could cause Low self-esteem (3) Distressing events or biological predisposition or could cause Low self-esteem and Depression 35
Correlation Problems with correlational research Which causes which? Third variable problem (confounding variables) Correlation does not demonstrate causation! 36
Illusory Correlation Illusory Correlation the perception of a relationship where none exists 37
Stereotypes are a good example of illusory correlations. Research has shown that people tend to assume that certain groups and traits occur together and frequently overestimate the strength of the association between the two variables. 38
Stereotypes are a good example of illusory correlations For example, let's suppose that a man holds a mistaken belief that all people from small towns are extremely kind. When the individual meets a very kind person, his immediate assumption might be that the person is from a small town, despite the fact that kindness is not related to city population. 39
Experimentation Experiment Scientists carry out experiments in an attempt to isolate cause and effect. an investigator manipulates one or more factors (independent variables) to observe their effect on some behavior or mental process (the dependent variable) by random assignment of participants the experiment controls other relevant factors 40
Experimentation Experimental Condition the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable Control Condition the condition of an experiment that contrasts with the experimental treatment serves as a comparison for evaluating the effect of the treatment 41
Experimentation Random Assignment assigning participants to experimental and control conditions by chance minimizes pre-existing differences between those assigned to the different groups 42
Random Assignment The Experimental Method Random Assignment Experimental Group #1 (High Noise) Experimental Group #2 (Low Noise) Control Group (No Noise) 43
Experimentation Independent Variable the experimental factor that is manipulated the variable whose effect is being studied For example, when studying the effect of a drug that reduces hyperactivity in children, the independent variable is the administration of the drug. When graphing, this data will be put on the x-axis. 44
Experimentation Dependent Variable the experimental factor that may change in response to manipulations of the independent variable in psychology it is usually a behavior or mental process For example, when studying the effects of a drug that may reduce hyperactivity in children, the amount of hyperactivity displayed would be the dependent variable. The dependent variable depends on the independent variable. When graphing, this data will be put on the y-axis. 45
Experimentation Independent variables Manipulated by the experimenter E.G. Noise Dependent variables Measured by the experimenter and influenced by the independent variable E.G. Learning 46
Experimentation Double-blind Procedure both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo commonly used in drug-evaluation studies Removes subtle and unintentional ways experimenters influence participants to conform to hypotheses. For example, in a drug trial, it is often preferable to ensure that even the physician is not aware of which patient is receiving the active drug and which is receiving the placebo. The physician may be tempted to give the sicker patients the drug which may skew the results. 47
Experimentation Placebo effect experimental results caused by expectations alone any effect on behavior caused by administration of an inert substance or condition, which is assumed to be an active agent In drug trials, it is often a sugar pill or an injection of saline causing the patient to assume that he is being treated with the active drug. The placebo is used in the control group. 48
Experimentation 49
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Statistical Reasoning Percentage still functioning after 10 years 100% 99 98 97 96 95 Our Brand Brand Brand Brand X Y Z Brand of truck 51
Statistical Reasoning Percentage still functioning after 10 years 100% 90 80 70 60 50 40 30 20 10 0 Our Brand Brand Brand Brand X Y Z Brand of truck 52
Statistical Reasoning Mode the most frequently occurring score in a distribution Mean the arithmetic average of a distribution obtained by adding the scores and then dividing by the number of scores Median the middle score in a distribution half the scores are above it and half are below 53 it
Statistical Reasoning A Skewed Distribution 15 20 25 30 35 40 45 50 90 475 710 70 Mode Median One Family Mean Income per family in thousands of dollars 54
Statistical Reasoning Range the difference between the highest and lowest scores in a distribution Standard Deviation a computed measure of how much scores vary around the mean Statistical Significance a statistical statement of how likely it is that an obtained result occurred by chance 55
Frequently Asked Questions about Psychology Can laboratory experiments illuminate everyday life? By intentionally creating a controlled, artificial environment in the lab, researchers aim to test theoretical principles. These principles help us to understand, describe, explain, and predict everyday behaviors. 56
Frequently Asked Questions about Psychology Does behavior depend on one s culture? Culture the enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next 57
Frequently Asked Questions about Psychology Attitudes and behaviors do vary across cultures, but the principles that underlie them vary much less. Cross-cultural psychology explores both our cultural differences and the universal similarities that define our human kinship. 58
Frequently Asked Questions about Psychology Does behavior vary with gender? Gender is a basic fact of life. Although gender differences tend to capture attention, it is important to remember our greater gender similarities. 59
Frequently Asked Questions about Psychology Why do psychologists study animals? Some psychologists study animals out of an interest in animal behavior. Others do so because knowledge of the physiological and psychological processes of animals gives them a better understanding of the similar processes operating in humans. 60
Frequently Asked Questions about Psychology Is it ethical to experiment on animals? Only about 7 percent of all psychological experiments involve animals, and under ethical and legal guidelines these animals rarely experience pain. Nevertheless, animal rights groups raise an important issue: Even if it leads to the relief of human suffering, is an animal s temporary suffering justified? 61
Frequently Asked Questions about Psychology Is it ethical to experiment on people? Occasionally researchers temporarily stress or deceive people in order to learn something important. Professional ethical standards provide guidelines concerning the treatment of both human and animal participants. 62
Frequently Asked Questions about Psychology Is psychology free of value judgments? 63
Frequently Asked Questions about Psychology Psychology is not value-free. Psychologists own values influence their choice of research topics, their theories and observations, their labels for behavior, and their professional advice. 64
Frequently Asked Questions about Psychology Is psychology potentially dangerous? Knowledge is power that can be used for good or evil. Applications of psychology s principles have so far been overwhelmingly for the good. Psychology addresses some of humanity s greatest problems and deepest longings. 65