Presentation on theme: "1 Research Strategies: How Psychologists Ask and Answer Questions Module 2."— Presentation transcript:
1 Research Strategies: How Psychologists Ask and Answer Questions Module 2
2 Why Do Psychology? The science of psychology helps make these examined conclusions, which leads to our understanding of how people feel, think, and act as they do!
3 What About Intuition & Common Sense? Many people believe that intuition and common sense are enough to bring forth answers regarding human nature. Intuition and common sense may aid queries, but they are not free of error. Human intuition is limited
4 The tendency to believe, after learning an outcome, that one would have foreseen it. We exaggerate our ability so foresee events. Hindsight Bias is the “I-knew- it-all-along” phenomenon. Hindsight Bias
6 Overconfidence Sometimes we think we know more than we actually know. Anagram BARGEGRABE ENTRYETYRN WATERWREAT
7 The Scientific Attitude The scientific attitude is composed of curiosity (passion for exploration), skepticism (doubting and questioning) and humility (ability to accept responsibility when wrong).
8 Critical Thinking Critical thinking does not accept arguments and conclusions blindly. It examines assumptions, discerns hidden values, evaluates evidence and assesses conclusions. /james_randi.htmlhttp://www.ted.com/talks/lang/eng /james_randi.html 17:20 The Amazing Randi Courtesy of the James Randi Education Foundation
9 How Do Psychologists Ask & Answer Questions? Psychologists, like all scientists, use the scientific method to construct theories that organize, summarize and simplify observations.
10 A theory is an explanation that integrates principles and organizes and predicts behavior or events. For example, low self-esteem contributes to depression. Theory
11 A hypothesis is a testable prediction, (often prompted by a theory), to enable us to accept, reject or revise the theory. A statement that can be tested with an experiment and gives direction to research People with low self-esteem are apt to feel more depressed. Hypothesis
12 Research would require us to administer tests of self-esteem and depression. Individuals who score low on a self-esteem test and high on a depression test would confirm our hypothesis. Research Observations
13 Operational definition A statement of the procedures used to define research variables Allows and facilitates replication of observations Operationally define shoe?
14 Description Case Study A technique in which one person is studied in depth to reveal underlying behavioral principles. Is language uniquely human? Susan Kuklin/ Photo Researchers
15 Survey The self-reported attitudes, opinions or behaviors of people.
17 The Lost Children of Rockdale County Studied a Syphilis epidemic at a high school in an affluent suburb of Atlanta
18 Survey Wording can change the results of a survey. Q: Should cigarette ads and pornography be allowed on television? (not allowed vs. forbid) Wording Effects
20 Sampling Random Sampling If each member of a population has an equal chance of inclusion into a sample, it is called a random sample (unbiased). The fastest way to know about the marble color ratio is to blindly transfer a few into a smaller jar and count them.
21 Sampling in Surveys Women and Love study done by Shere Hite % Dissatisfied by their Marriage 75% Extramarital Affairs But to all of those who were mailed surveys only 4% responded.
22 When randomly sampled 93% of women are satisfied in their marriages Only 7% had affairs
23 Naturalistic Observation Observing and recording the behavior of organisms in their natural environment without interfering.
24 Comparison Summary Research MethodAdvantagesLimitations Naturalistic Observation More accurate than reports after the fact Behavior is more natural Observer can alter behavior Observational Bias Cannot be generalized Case Studies Depth Takes advantage of circumstances that could not be coordinated in an experiment Not representative Time consuming and expensive Observational Bias Surveys Immense amount of data Quick and inexpensive Sampling biases can skew results Bad Questions can corrupt data Accuracy depends on the ability and willingness of the participants.
25 Correlation When one trait or behavior accompanies another, we say the two correlate. Correlation coefficient Indicates direction of relationship (positive or negative) Indicates strength of relationship (0.00 to 1.00) r = Correlation Coefficient is a statistical measure of the relationship between two variables.
26 or Correlation and Causation Correlation does not mean causation!
27 Illusory Correlation The perception of a relationship where no relationship actually exists. Parents conceive children after adoption.
28 Correlation is not Causation: It only predicts!!!! Children with big feet reason better than children with small feet. –(Children who are older have bigger feet than younger children; thus they can reason better) Study done in Korea: The most predictive factor in the use of birth control use was the number of appliances in the home. –(Those who have electrical appliances probably have higher socioeconomic level, and thus are probably better educated.)
29 Correlation is not Causation: It only predicts!!!! People who often ate Frosted Flakes as children had half the cancer rate of those who never ate the cereal. Conversely, those who often ate oatmeal as children were four times more likely to develop cancer than those who did not. Study done in Korea –Cancer tends to be a disease of later life. Those who ate Frosted Flakes are younger. In fact, the cereal was not around until the 1950s (when older respondents were children, and so they are much more likely to have eaten oatmeal.)
30 Ice cream sales and the number of shark attacks on swimmers are correlated. Skirt lengths and stock prices are highly correlated (as stock prices go up, skirt lengths get shorter). The number of cavities in elementary school children and vocabulary size are strongly correlated.
31 Illusory Correlations Redelmeier and Tversky (1996) assessed 18 arthritis patients over 15 months, while also taking comprehensive meteorological data. Virtually all of the patients were certain that their condition was correlated with the weather. In fact the actual correlation was close to zero.
34 In a Gallup poll, surveyors asked, “Do you believe correlation implies causation?’” 64% of American’s answered “Yes”. 38% replied “No”. The other 8% were undecided.
35 Perfect positive correlation (+1.00) Scatter plot is a graph comprised of points that are generated by values of two variables. The slope of the points depicts the direction, while the amount of scatter depicts the strength of the relationship. Scatter plots & Correlation
36 No relationship (0.00) Perfect negative correlation (-1.00) The Scatter plot on the left shows a negative correlation, while the one on the right shows no relationship between the two variables. Scatter plots & Correlation
38 Describing Data A meaningful description of data is important in research. Misrepresentation may lead to incorrect conclusions.
39 Measures of Variation 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.
40 Normal Curve A symmetrical, bell-shaped curve that describes the distribution of many types of data (normal distribution). Most scores fall near the mean.
41 Given random data, we look for order and meaningful patterns. Order in Random Events Your chances of being dealt either of these hands is precisely the same: 1 in 2,598,960.
42 Order in Random Events Given large numbers of random outcomes, a few are likely to express order. Angelo and Maria Gallina won two California lottery games on the same day. Jerry Telfer/ San Francisco Chronicle Find a string in Pi
43 Experimentation Experimentation is the backbone of psychological research. Experiments isolate causes and their effects.
44 Many factors influence our behavior. Experiments (1) manipulate factors that interest us, while other factors are kept under (2) control. Effects generated by manipulated factors isolate cause and effect relationships. Exploring Cause & Effect
45 Evaluating Therapies Double-blind Procedure Neither the participant nor the research assistant knows whether the participant is receiving the treatment or a placebo
46 Longitudinal Studies –Studies where the same subjects are studied over a period of time Cross Sectional studies –Studies where different subjects are studied at from a variety of age groups
47 Example of Experimenter Bias Had subjects rated neutral photos Those experimenters who were led to expect positive answers achieved positive results. Those experimenters who were led to expect negative answers achieved negative results
49 Placebo Effect A change in an illness or behavior that results from a belief that the treatment will have an effect People react to their own positive expectations
53 Placebo Surgery?
54 "The fact that the effectiveness of arthroscopic lavage and debridement in patients with osteoarthritis of the knee is no greater than that of placebo surgery makes us question whether the $1 billion spent on these procedures might be put to better use."
56 Nocebo Effect … people get worse because they believe they'll get worse. Expectation alone can made healthy people ill.
57 Breast feeding example: Assigning participants to experimental (breast-fed) and control (formula-fed) conditions by random assignment minimizes pre- existing differences between the two groups. Evaluating Therapies Random Assignment
58 An independent variable is a factor manipulated by the experimenter. The effect of the independent variable is the focus of the study. For example, when examining the effects of breast feeding upon intelligence, breast feeding is the independent variable. Independent Variable IV
59 A dependent variable is a factor that may change in response to an independent variable. In psychology, it is usually a behavior or a mental process. For example, in our study on the effect of breast feeding upon intelligence, intelligence is the dependent variable. Dependent Variable DV
60 Experimentation A summary of steps during experimentation.
61 FAQ Q1. Can laboratory experiments illuminate everyday life? Q2. Does behavior depend on one’s culture and gender? Q3. Why do psychologists study animals, and is it ethical to experiment on animals?
62 FAQ Q4. Is it ethical to experiment on people? Q5. Is psychology free of value judgments? Q6. Is psychology potentially dangerous?
64 Variable 2 21 Variable Hypothetical data illustrating a correlation coefficient of +1.00
65 Hypothetical data illustrating a correlation coefficient of Variable 2 21 Variable
66 Fig. 2.4 Hypothetical data illustrating a correlation coefficient of zero Variable 2 21 Variable
67 Data Data showing height and temperament in people.
68 Scatterplot The Scatterplot below shows the relationship between height and temperament in people. There is a moderate positive correlation of
69 Measures of Central Tendency A Skewed Distribution
70 Skewed Distributions Positive Mean > Median Negative Mean < Median
71 Standard Deviation
72 Standard Deviation in Action A couple needs to be within one standard deviation of each other in intelligence (10 points in either direction). —Neil Clark Warren, founder of eHarmony.com
73 Normal Distribution 1SD 68%
74 Normal Distribution 2 SD 95%
79 Measures of Central Tendency Mode: The most frequently occurring score in a distribution. Mean: The arithmetic average of scores in a distribution obtained by adding the scores and then dividing by the number of scores that were added together. Median: The middle score in a rank-ordered distribution.