Thinking Critically With Psychological Science

Transcription

1 Why Do Psychology? Thinking Critically With Psychological Science Chapter 1 1. How can we differentiate between uniformed opinions and examined conclusions? 2. The science of psychology helps make these examined conclusions, which leads to our understanding of how people feel, think, and actas they do! 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. Personal interviewers may rely too much on their gut feelings when meeting with job applicants. (gut feelings are often formed by common sense) I have a feeling it is going to rain. I have a feeling we are going to win. I have a feeling this is my soul mate. Limits of Intuition Taxi/ Getty Images Hindsight Bias Hindsight Biasis the I-knew-it-all-along phenomenon. After learning the outcome of an event, many people believe they could have predicted that very outcome. We only knew the dot.com stocks would plummet after they actually did plummet. I knew they were going to have a baby boy! I knew the Panthers were going to beat the Sharks I knew Zimmerman was going to be let go Overconfidence Sometimes we think we know more than we actually know. How long do you think it would take to unscramble these anagrams? Most people said it would take about 10 seconds, yet on average they took about 3 minutes (Goranson, 1978). WREAT ETYRN GRABE Anagram WATER ENTRY BARGE 1

2 How popular are you at school? Studies show that in a school setting that 60% of the students rated themselves to be in the top 25% of the popular kids. 25% of the students rated themselves in the top 1%. As a teacher I may have a really good week in the classroom and feel really good about how my students are picking up the new material. However, this overconfidence often lets me down after seeing many low scores on a test. Ever hear someone say after they may have had to much to drink, I drive better when I have been drinking because I pay closer attention to what I am doing? A little over confident you think? Don t let them drive!!! By the way Studies show that boys are tremendously over confident in their ability to drive. 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). Curiosity: without being misled, does it work? When tested, can its predictions be confirmed? Skepticism: be open but not gullible. Scrutinizing crazy ideas sometimes prove there might be some truth behind it. Sometimes it will debunk previous thought. (Earth is flat) Humility: awareness that being wrong is okay. Be open to other ideas and perspectives. Do not fear failure! Failures often give up and stop searching for answers. Critical Thinking Critical thinking does not accept arguments and conclusions blindly. It examines assumptions, discerns hidden values, evaluates evidence and assesses conclusions. CT asks questions like: How do we know that? What is the answer based off of? Does the answer ever change or is it always the same? How Do Psychologists Ask & Answer Questions? Psychologists, like all scientists, use the scientific method to construct theories that organize, summarize and simplify observations. Theory = a mere hunch -not proven However, a scientific theory does explain through observations to allow predictions 2

3 Theory Atheory isan explanation that integrates principles and organizes and predicts behavior or events. For example, low self-esteem contributes to depression. We must test this to see if theory is even plausible. Hypothesis Ahypothesisis a testable prediction, often prompted by a theory, to enable us to accept, reject or revise the theory. People with low self-esteem are apt to feel more depressed. It gives us direction to research. It specifies what results support our theory and what would disprove our theory. Research Observations Researchwould 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. The more we replicate the same results the more confidence we gain in our theory. Theories lead to the need for a hypothesis This leads to the need for research and observe Through this we are able to confirm, reject, or revise our theories Research Process 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 Example The story of Genie This case study allows psychologists, sociologists, linguistic professionals, etc to study her up bringing and her disabilities in order to compare them to others who have been treated in similar situations. It allows the researchers to predict the future and make a plan of action for others. 3

4 Survey A technique for ascertaining the self-reported attitudes, opinions or behaviors of people usually done by questioning a representative, random sample of people. Survey Wording Effects Wording can change the results of a survey. Q: Should cigarette ads and pornography be allowed on television? (not allowed vs. forbid) Survey If each member of a population has an equal chance of inclusion into a sample, it is called a random sample (unbiased). If the survey sample is biased, its results are not valid. Random Sampling The fastest way to know about the marble color ratio is to blindly transfer a few into a smaller jar and count them. Lets say we want to figure out how many people in Jacksonville who have a phone listed in the phone book use the local beach more than twice a year. Do we call everyone in the phone book? Do we call a random sample? How might we go about doing this? Naturalistic Observation Observing and recording the behavior of animals in the wild and recording self-seating patterns in a multiracial school lunch room constitute naturalistic observation. Another example Naturalistic Observation A boy drops a book in the hallway A girl drops a book in the hallway Wearing a fat suit for a semester or changing the color of your hair, or wearing off brand clothes Courtesy of Gilda Morelli Police allowing one of their own into a violent gang for a couple years 4

5 Naturalistic Observation Disadvantages It may be difficult to determine exact cause of a behavior Experimenter cannot control outside Different observers may draw different variables and conclusions If in a situation where the group being studied knows you are there observing, the group may behave differently. They may also behave the way they think the researcher wants them to behave. Descriptive Methods Summary Case studies, surveys, and naturalistic observation describe behaviors. Correlation When one trait or behavior accompanies another, we say the two correlate. They share the same kind of relationship. Indicates strength of relationship (0.00 to 1.00) Causation Means that one variable causes something to happen in another variable Correlation coefficient r = Correlation Coefficient is a statistical measure of the relationship between two variables. Indicates direction of relationship (positive or negative) Scatterplots Scatterplots Study Time Party Time Body Weight Perfect positive correlation (+1.00) Test Scores Scatterplotis 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. A correlation is positive if 2 sets of scores tend to rise or fall together Perfect negative correlation (-1.00) Test Scores No relationship (0.00) The Scatterplot on the left shows a negative correlation, while the one on the right shows no relationship between the two variables. A correlation is negative if 2 sets of scores relate inversely (one goes up and the other goes down) Test Scores 5

6 Data Data showing height and temperament in people. Scatterplot The Scatterplot below shows the relationship between height and temperament in people. There is a moderate positive correlation of Correlation and Causation Correlation does not mean causation!!! Example or Since Mexican Lemons and oranges have been imported into the U.S. the nation has seen a decrease in casualties in traffic accidents. 1 Study had monkey s drive motorcycles and cars on the highway having a bag of Mexican Citrus strapped to their back. Since being tested over the years we have seen a correlation of the two. Question. Is this causation??? What might be the real cause of increased Mexican citrus in the U.S.? What might be the real cause of fewer accidents on the roads by motorists in the U.S.? Real data could actually show the two things being true but likely the increase in Mexican Citrus is probably due to some economic factor(s) while the decrease in fatalities in traffic accidents could be due to newer technology that helps protect the vehicles passengers all happening in the same time frame. 6

7 Correlation does not mean causation!!! Student Average minutes spent studying Score on first Test By looking at this data it looks as if there is a relationship. If you imply there is a relationship you need to experiment to prove your results or debunk them. Illusory Correlation The perception of a relationship where no relationship actually exists. Many superstitions begin this way. Not only did I play well today but my team won. We never win. But I never had a hole in my sock like I did today. The 2 must be correlated. The person who scored the highest may have put the most study time in but they may be stronger in the social studies area, or had tutor help, or read different sources, or have taken the same course before or may have cheated etc Order in Random Events Given random data, we look for order and meaningful patterns. Order in Random Events Given large numbers of random outcomes, a few are likely to express order. Your chances of being dealt either of these hands is precisely the same: 1 in 2,598,960. Angelo and Maria Gallina won two California lottery games on the same day. Jerry Telfer/ San Francisco Chronicle Experimentation Exploring Cause and Effect Like other sciences, experimentation is the backbone of psychological research. Experiments isolate causes and their effects. Exploring Cause & Effect Many factors influence our behavior. Experiments (1)manipulatefactors that interest us, while other factors are kept under (2) control. Effects generated by manipulated factors isolate cause and effect relationships. 7

8 Evaluating Therapies Double-blind Procedure In evaluating drug therapies, patients and experimenter s assistants should remain unaware of which patients had the real treatment and which patients had the placebo treatment. This is good for creating an experimental group and control group. Evaluating Therapies Random Assignment Assigning participants to experimental (breastfed) and control (formula-fed) conditions by random assignment minimizes pre-existing differences between the two groups. Hypothesis: breast-fed babies have higher intelligence Independent Variable An independent variableis 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 feedingis the independent variable. The IV is the manipulated variable. It is the one researchers change in order to make the DV occur. Hint: look for this second. What do the researchers hope will cause the DV in the study? Dependent Variable Adependent variableis 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. The DV is the measured variable. It is the variable that researchers expect will occur. Hint: look for this one first. What is the researcher looking for or measuring in the study? Experimentation A summary of steps during experimentation. Dependent and independent variables Lets say we wanted to find out if kids with heavy book bags scored higher on class grades including tests. Which is the independent variable? Weight of the book bag Which is the dependent variable? Scores on class grades and tests The independent variable stands alone but the dependent variable depends on the independent variable 8

9 Try this one I have made a magic pill. What s in it??? Who cares.. It cures Cancer Hypothesis is the magic pill cures cancer How do I set up my experiment to get results that the FDA would approve to make me a Trillionaire? Variables: what is the IV and what is the DV? Independent Variable pill or placebo Dependent Variable the new outcome after receiving the pill or Placebo How will I set this up? Take ½ class and give them magic pill Experimental group. other ½ receives the Placebo a sugar pill This would be my control group Yes a sugar pill. This combats the Placebo effect- when someone suffers from pain, depression, anxiety, etc. THAT if you THINK your are receiving medication, your body will relax, your mood will be better, and you will even experience symptom relief. New Example I am going to keep you engaged in class with a facial expression (a wink). What is my independent variable? Wink or no wink What is my dependent variable? Being engaged in class Control group (½ class) on left get a the normal me Experimental (other ½ class) get a big wink.boy that worked well. You guys look really engaged How do we control ME seeing what I want to see??? Try to eliminate demand characteristics psychological term used in experiments to describe a cue that makes the participants aware of what the experimenter expects to find or how they should behave. These can change the outcome of the experiment due to them wanting to conform to the behavior. Hawthorne Effect fact that people try to improve behavior because they know they are being studied Control- single blind experiment- Experimenter knows who got placebo and who got medicine Double blind- the use of numbers so neither patients nor Dr. know who has what Comparison Below is a comparison of different research methods. The only type of study that can determine cause and effect is the experiment. Students often miss this distinction!!! 9

10 Statistical Reasoning Statistical procedures analyze and interpret data allowing us to see what the unaided eye misses. Statistical Reasoning in Everyday Life Doubt big, round, undocumented numbers as they can be misleading and before long, become public misinformation. Apply simple statistical reasoning in everyday life to think smarter! Composition of ethnicity in urban locales Describing Data A meaningful description of data is important in research. Misrepresentation may lead to incorrect conclusions. (Both charts are of the same data) 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. 13,18,13,14,13,16,14,21,13 Mean is the usual average: ( ) divide by 9 = 15 Mean = 15 Median is the middle value. Rewrite the list in ascending order 13,13,13,13,14,14,16,18,21 Median = 14 Mode is the # represented most often. 13 is repeated 4 times 14 is repeated 2 times 16,18,21 are not repeated at all 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. 10

11 Measures of Central Tendency A Skewed Distribution 13,13,13,13,14,14,16,18,21 Revisiting our list in ascending order from a few slides ago we see that the largest value in the list is 21 and the smallest is =8 Range = 8 $70,000 dollars is the average income per family in this area. However, only 4 families in this area even make $70,000/year or more while 26 families make $50,000 or less. Normal Curve A symmetrical, bell-shaped curve that describes the distribution of many types of data (normal distribution). Most scores fall near the mean. Illusion of Control That chance events are subject to personal control is an illusion of control fed by: 1. Illusory Correlation: the perception of a relationship where no relationship actually exists. 2. Regression Toward the Mean:the tendency for extremes of unusual scores or events to regress toward the average. Making Inferences A statistical statement of how frequently an obtained result occurred by experimental manipulation or by chance. Making Inferences When is an Observed Difference Reliable? 1. Representative samples are better than biased samples. 2. Less-variable observations are more reliable than more variable ones. 3. More cases are better than fewer cases. 11

12 Making Inferences When is a Difference Significant? When sample averages are reliable and the difference between them is relatively large, we say the difference has statistical significance. It is probably not due to chance variation. Frequently Asked Questions About Psychology Q1.Can laboratory experiments illuminate everyday life? Ans:Artificial laboratory conditions are created to study behavior in simplistic terms. The goal is to find underlying principles that govern behavior. FAQ Q2. Does behavior depend on one s culture and gender? Ans: Even when specific attitudes and behaviors vary across cultures, as they often do, the underlying processes are much the same. Biology determines our sex, and culture further bends the genders. However, in many ways woman and man are similarly human. FAQ Q3.Why do psychologists study animals, and is it ethical to experiment on animals? Ans: Studying animals gives us the understanding of many behaviors that may have common biology across animals and humans. From animal studies, we have gained insights to devastating and fatal diseases. All researchers who deal with animal research are required to follow ethical guidelines in caring for these animals. Ami Vitale/ Getty Images D. Shapiro, Wildlife Conservation Society FAQ Q4.Is it ethical to experiment on people? Ans: Yes. Experiments that do not involve any kind of physical or psychological harm beyond normal levels encountered in daily life may be carried out. FAQ Q5. Is psychology free of value judgments? Ans: No. Psychology emerges from people who subscribe to a set of values and judgments. 12

13 FAQ Q6. Is psychology potentially dangerous? Ans: It can be, but is not when practiced responsibly. The purpose of psychology is to help humanity with problems such as war, hunger, prejudice, crime, family dysfunction, etc. 13