AP Psychology Unit 2
The Need for Psychological Science (Mod 4)
Hindsight Bias—tendency to believe, after learning an outcome, that one would have foreseen it
“I knew it all along” phenomenon
Overconfidence—we tend to think we know more than we do
Richard Goranson Study—people predicted that they would take seconds to unscramble simple words, yet it took them an average of 3 minutes
Become confident even when we’re not
People will believe you if you act confident—even if you have no idea what you’re talking about
Perceiving Order in Random Events
Comes from our great need to make sense out of the world
Coin flip—you are just as likely to get heads every time than a bunch of random results
We try to look for patterns where patterns do not exist
The Scientific Attitude: Curious, Skeptical, and Humble
Curious eagerness—want to learn about the world
Skeptical scrutinization—don’t blindly believe everything
Humble open-mindedness—accept and listen to ideas from all sides
Hindsight bias, overconfidence, and our tendency to perceive patterns in random events lead us to overestimate our intuition
Critical thinking—thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluated evidence, and assesses conclusions
Political ads—know their hidden agenda, evaluate their evidence, know that a lot is taken out of context, make your own conclusions
The Scientific Method and Description (Mod 5)
Theory—an explanation using an integrated set of principles that organizes observations and predicts behaviors or events
“Mere hunch”
Hypothesis—a testable prediction, often implied by a theory
Can be confirmed or refuted
In psychology, often about whether variables are related or not
Operational definition—a carefully worded statement of the exact procedures (operations) used in a research study
A recipe for banana bread that explains in detail exactly what needs to be done to make the exact same, precise loaf of banana bread
Effects of video games on children—what ages? What happens when they are playing multiplayer and one child is watching the other when it is their turn?
Replication—repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances
The Scientific Method
Theories—sleep boosts memory
A good theory is useful if it
Effectively organizes a range of self-reports and observations
Leads to clear hypotheses that anyone can use to check it
Often stimulates research that leads to a revised theory that better predicts what we know
Hypothesis—When people are sleep deprived, they remember less from the day before
Research and observations—Give study material to people before (a) a good night’s sleep, or (b) a shortened night’s sleep, then test memory
Make adjustments and test again
Case Study—a descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles
Hoping that the findings can be generalized, but that is hard to prove
Problems with atypical individuals
Very time- and cost-intensive—putting all your eggs in one basket
Naturalistic observation—observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation
I don’t know why the student took a drink, but I can say that she picked up the water bottle and drank it
Do it a lot with animals—we don’t know what they’re thinking, we can only describe what they do
Strictly watching and recording—does not explain
Survey—a technique for ascertaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.
Quick and easy way to collect information
Assumes people are being truthful—people may lie, you cannot know for sure
Wording of questions affects people’s answers
“How much would you support helping the needy” versus “How much would you support welfare” or “Revenue enhancers” versus “taxes”
Try not to use loaded language
Population—hard to ask every single person in the population, so use a sample
Random and representative sample
Only asking Bay Port teenagers for their opinions doesn’t represent all Green Bay teenagers
Choose the people at random—don’t handpick
Sampling Bias—a flawed sampling process that is produced by using an unrepresentative sample
Correlation and Experimentation (Mod 6)
Correlation—a measure of the extent to which two factors change together, and thus of how well either factor predicts the other
How two things are related
Correlation Coefficient—a statistical index of the relationship between two things (from -1.0 to +1.0)
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 between two variables. The amount of scatter suggests the strength of the correlation (little scatter indicates high correlation)
Correlation does not mean causation, it only helps to predict
Ex. higher ice cream sales have a positive correlation with drowning death—confounding variable could be temperature (more people swimming and buying ice cream in the summer)
Illusory Correlation—the perception of a relationship where none exists
Ex. A couple tries to conceive for years and once they adopt a child, they become pregnant—ignores all of the other times where people adopt and don’t get pregnant, etc.
Experiment—a research method in which an investigator manipulates one or more factors (independent variables) to observe the effect on some behavior or mental process (the dependent variable). By random assignment of participants, the experimenter aims to control other relevant factors.
How does caffeine affect attention span?
Experimental Group—in an experiment, the group that is exposed to the treatment, that is, to one version of the independent variable
The group given the caffeine
Control Group—in an experiment, the group that is NOT exposed to the treatment; contrasts with the experimental group and serves as a comparison for COME BACK
The group not given the caffeine
Random assignment—assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between those assigned to the different groups
Different from random sample
Blind (uninformed)
Single-blind: person in experiment does not know which group they are in
Double-Blind Procedure—an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or the placebo. Commonly used in drug-evaluation studies
Placebo Effect—experimental results caused by expectation alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent
Latin for “I shall please”
Independent and Dependent Variables
Independent Variable—the experimental factor that is manipulated; the variable whose effect is being studied
The presence or absence of caffeine
Confounding Variable—a factor other than the independent variable that might produce an effect in an experiment
Ex. if the drinking experiment (people weren’t actually given alcohol) was in a lab or classroom instead of a bar, the result would’ve been different
Effect of random assignment on confounding variables
Dependent Variable—the outcome factor; the variable that may change in response to manipulations of the independent variable
The attention span as a result of having or not having caffeine
Validity—the extent to which a test or experiment measures or predicts what it is supposed to
Giving a math test isn’t a good way to measure psychology knowledge, therefore the test is not valid to test psychology knowledge
Statistical Reasoning in Everyday Life (Mod 7)
Understanding basic statistics is beneficial for everyone
Descriptive Statistics—numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variability
Histogram—a bar graph depicting a frequency distribution
Can be exaggerated—be careful (look at scale on y-axis)
Measures of central tendency
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 it
Mode—the most frequently occurring score(s) in a distribution
Skewed Distribution—a representation of scores that lack symmetry around their average value
Measures of Variability
Range—the difference between the highest and lowest score in a distribution
Standard Deviation—a computed measure of how much scores vary around the mean score
Normal Curve—a symmetrical, bell-shaped curve that describes the distribution of many types of data; most scored fall near the mean (68 percent fall within one standard deviation of it) and fewer and fewer near the extremes
Normal distribution
Inferential Statistics—numerical data that allow one to generalize—to infer from sample data the probability of something being true to a population
When is an observed difference reliable?
Representative samples are better than biased samples
More cases are better than fewer
When is a difference significant?
Statistical Significance—a statistical statement of how likely it is that an obtained result occurred by chance
Averages are reliable, differences between averages are relatively large
Frequently Asked Questions about Psychology (Mod 8)
Psychology Applied
Can laboratory experiments illuminate everyday life?
The principles, not the research findings, help explain behavior
Does behavior depend on one’s culture and gender?
Culture—the enduring behavior, ideas, attitudes, and traditions shared by a group of people and transmitted from one generation to the next
Yes!
Ethics in Research
Animal research
Humans are animals so a lot we learn about them can be transferred to us
Controversial because harm can be caused to animals
Safeguards—ethics committee
Human Research
Informed consent—an ethical principle that research participants be told enough to enable them to choose whether they wish to participate
Caffeine study—tell participants all possible effects of the caffeine, if there are large risks, etc.
Must protect participants from harm or discomfort as best as you can
Confidentiality—keep their data apart from their name
Debriefing—the postexperimental explanation of a study, including its purpose and any deceptions, to its participants
Caffeine study—here’s what group you were in, some of the puzzles were actually unsolvable, here’s our contact information if you have any questions, etc.
The Need for Psychological Science (Mod 4)
Hindsight Bias—tendency to believe, after learning an outcome, that one would have foreseen it
“I knew it all along” phenomenon
Overconfidence—we tend to think we know more than we do
Richard Goranson Study—people predicted that they would take seconds to unscramble simple words, yet it took them an average of 3 minutes
Become confident even when we’re not
People will believe you if you act confident—even if you have no idea what you’re talking about
Perceiving Order in Random Events
Comes from our great need to make sense out of the world
Coin flip—you are just as likely to get heads every time than a bunch of random results
We try to look for patterns where patterns do not exist
The Scientific Attitude: Curious, Skeptical, and Humble
Curious eagerness—want to learn about the world
Skeptical scrutinization—don’t blindly believe everything
Humble open-mindedness—accept and listen to ideas from all sides
Hindsight bias, overconfidence, and our tendency to perceive patterns in random events lead us to overestimate our intuition
Critical thinking—thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluated evidence, and assesses conclusions
Political ads—know their hidden agenda, evaluate their evidence, know that a lot is taken out of context, make your own conclusions
The Scientific Method and Description (Mod 5)
Theory—an explanation using an integrated set of principles that organizes observations and predicts behaviors or events
“Mere hunch”
Hypothesis—a testable prediction, often implied by a theory
Can be confirmed or refuted
In psychology, often about whether variables are related or not
Operational definition—a carefully worded statement of the exact procedures (operations) used in a research study
A recipe for banana bread that explains in detail exactly what needs to be done to make the exact same, precise loaf of banana bread
Effects of video games on children—what ages? What happens when they are playing multiplayer and one child is watching the other when it is their turn?
Replication—repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances
The Scientific Method
Theories—sleep boosts memory
A good theory is useful if it
Effectively organizes a range of self-reports and observations
Leads to clear hypotheses that anyone can use to check it
Often stimulates research that leads to a revised theory that better predicts what we know
Hypothesis—When people are sleep deprived, they remember less from the day before
Research and observations—Give study material to people before (a) a good night’s sleep, or (b) a shortened night’s sleep, then test memory
Make adjustments and test again
Case Study—a descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles
Hoping that the findings can be generalized, but that is hard to prove
Problems with atypical individuals
Very time- and cost-intensive—putting all your eggs in one basket
Naturalistic observation—observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation
I don’t know why the student took a drink, but I can say that she picked up the water bottle and drank it
Do it a lot with animals—we don’t know what they’re thinking, we can only describe what they do
Strictly watching and recording—does not explain
Survey—a technique for ascertaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.
Quick and easy way to collect information
Assumes people are being truthful—people may lie, you cannot know for sure
Wording of questions affects people’s answers
“How much would you support helping the needy” versus “How much would you support welfare” or “Revenue enhancers” versus “taxes”
Try not to use loaded language
Population—hard to ask every single person in the population, so use a sample
Random and representative sample
Only asking Bay Port teenagers for their opinions doesn’t represent all Green Bay teenagers
Choose the people at random—don’t handpick
Sampling Bias—a flawed sampling process that is produced by using an unrepresentative sample
Correlation and Experimentation (Mod 6)
Correlation—a measure of the extent to which two factors change together, and thus of how well either factor predicts the other
How two things are related
Correlation Coefficient—a statistical index of the relationship between two things (from -1.0 to +1.0)
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 between two variables. The amount of scatter suggests the strength of the correlation (little scatter indicates high correlation)
Correlation does not mean causation, it only helps to predict
Ex. higher ice cream sales have a positive correlation with drowning death—confounding variable could be temperature (more people swimming and buying ice cream in the summer)
Illusory Correlation—the perception of a relationship where none exists
Ex. A couple tries to conceive for years and once they adopt a child, they become pregnant—ignores all of the other times where people adopt and don’t get pregnant, etc.
Experiment—a research method in which an investigator manipulates one or more factors (independent variables) to observe the effect on some behavior or mental process (the dependent variable). By random assignment of participants, the experimenter aims to control other relevant factors.
How does caffeine affect attention span?
Experimental Group—in an experiment, the group that is exposed to the treatment, that is, to one version of the independent variable
The group given the caffeine
Control Group—in an experiment, the group that is NOT exposed to the treatment; contrasts with the experimental group and serves as a comparison for COME BACK
The group not given the caffeine
Random assignment—assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between those assigned to the different groups
Different from random sample
Blind (uninformed)
Single-blind: person in experiment does not know which group they are in
Double-Blind Procedure—an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or the placebo. Commonly used in drug-evaluation studies
Placebo Effect—experimental results caused by expectation alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent
Latin for “I shall please”
Independent and Dependent Variables
Independent Variable—the experimental factor that is manipulated; the variable whose effect is being studied
The presence or absence of caffeine
Confounding Variable—a factor other than the independent variable that might produce an effect in an experiment
Ex. if the drinking experiment (people weren’t actually given alcohol) was in a lab or classroom instead of a bar, the result would’ve been different
Effect of random assignment on confounding variables
Dependent Variable—the outcome factor; the variable that may change in response to manipulations of the independent variable
The attention span as a result of having or not having caffeine
Validity—the extent to which a test or experiment measures or predicts what it is supposed to
Giving a math test isn’t a good way to measure psychology knowledge, therefore the test is not valid to test psychology knowledge
Statistical Reasoning in Everyday Life (Mod 7)
Understanding basic statistics is beneficial for everyone
Descriptive Statistics—numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variability
Histogram—a bar graph depicting a frequency distribution
Can be exaggerated—be careful (look at scale on y-axis)
Measures of central tendency
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 it
Mode—the most frequently occurring score(s) in a distribution
Skewed Distribution—a representation of scores that lack symmetry around their average value
Measures of Variability
Range—the difference between the highest and lowest score in a distribution
Standard Deviation—a computed measure of how much scores vary around the mean score
Normal Curve—a symmetrical, bell-shaped curve that describes the distribution of many types of data; most scored fall near the mean (68 percent fall within one standard deviation of it) and fewer and fewer near the extremes
Normal distribution
Inferential Statistics—numerical data that allow one to generalize—to infer from sample data the probability of something being true to a population
When is an observed difference reliable?
Representative samples are better than biased samples
More cases are better than fewer
When is a difference significant?
Statistical Significance—a statistical statement of how likely it is that an obtained result occurred by chance
Averages are reliable, differences between averages are relatively large
Frequently Asked Questions about Psychology (Mod 8)
Psychology Applied
Can laboratory experiments illuminate everyday life?
The principles, not the research findings, help explain behavior
Does behavior depend on one’s culture and gender?
Culture—the enduring behavior, ideas, attitudes, and traditions shared by a group of people and transmitted from one generation to the next
Yes!
Ethics in Research
Animal research
Humans are animals so a lot we learn about them can be transferred to us
Controversial because harm can be caused to animals
Safeguards—ethics committee
Human Research
Informed consent—an ethical principle that research participants be told enough to enable them to choose whether they wish to participate
Caffeine study—tell participants all possible effects of the caffeine, if there are large risks, etc.
Must protect participants from harm or discomfort as best as you can
Confidentiality—keep their data apart from their name
Debriefing—the postexperimental explanation of a study, including its purpose and any deceptions, to its participants
Caffeine study—here’s what group you were in, some of the puzzles were actually unsolvable, here’s our contact information if you have any questions, etc.