AP Psychology: Chapter 1: Thinking Critically With Psychological Science

Solve ME A man is traveling from work and wants to go home. He will not go home because there is another man in a mask waiting there for him. What does the first man do for a living? The man is a runner at third base and he is trying to score a run

Solve ME A man is found shot to death in a room with a table, four chairs, and 53 bicycles. Why was he murdered? There are 52 Bicycle playing cards in a normal deck. He was playing with an extra ace.

What is critical thinking? How does it relate to psychology and this course?

Let’s Make A Deal! One Volunteer is Needed for A chance to win 10, Zimbabwe Dollars!!

Let’s Make A Deal Shows Us That: Human Intuition is highly limited. Critically thinking rarely comes easily to us! – Critical Thinking: thinking that does not blindly accept arguments and conclusions examines assumptions discerns hidden values evaluates evidence An awareness to our own vulnerability

Lack of Intuition Hindsight Bias: tendency to believe, after learning an outcome, that one would have foreseen it. the “I-knew-it-all-along” phenomenon

Lack Of Intuition Overconfidence: we tend to think we know more than we do. We can't always trust our common sense or intuition we need research

Research Strategies Theory – an explanation using an integrated set of principles that organizes and predicts observations – Low self esteem contributes to depression Hypothesis – a testable prediction – often implied by a theory – Allows us to test and reject or revise the theory – People with low self esteem score higher on a depression scale

Scientific Method generate or refine research and observations lead to hypothesis theories lead to

How to check our bias Operational Definition – a statement of procedures (operations) used to define research variables – You want to be clear enough so that the test and observations can be replicated – To give the study more credibility it is usually done with different subjects in different situations – Make sure studies are valid and reliable

Research Strategies 1. Descriptive- making observations that describe behavior 2. Correlational- detecting correlations that help predict behavior 3. Experimental-doing studies that help explain behavior

Research Methods- Descriptive Case Study – an observation technique in which one person is studied in depth in the hope of revealing universal principles – Longitudinal – Cross Sectional – Drawbacks of case study: individuals can be atypical and lead to false findings. Anecdotal Stories

Research Methods- Descriptive and Correlation Survey – technique for ascertaining the self- reported attitudes or behaviors of people – usually by questioning a representative, random sample of them

Components of Survey Population: all the individuals you are interested in knowing something about. Sample: the individuals you actually question. Sampling should always be taken randomly from the population so that it is representative, meaning each individual in the population had an equal chance of being selected.

Drawbacks of Surveys 1.) Improper Sampling 2.) Question Wording Can Effect the results of a survey. Ex: Should the sale of alcohol be banned in school zones? Should the government not allow the sale of alcohol in school zones?

Importance of Proper Sampling False Consensus Effect: tendency to overestimate the extent to which others share our beliefs and behaviors. Overgeneralizing extreme examples can lead you to false conclusions!

Types of Research-Descriptive Naturalistic Observation: observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation Drawbacks: hard to identify any type of causation since there is no controls.

Correlation Research Correlation Research: research that looks at a relationship between two things. How well does one factor predict the other? Ex: Consumption of Ice Cream and Drowning.

Types of Correlations Positive Correlation: a relationship in which increases in one variable leads to increases in the other. Ex: Amount of fat burned is positively correlated with amount of sit-ups completed Negative Correlation: a relationship in which increases in one variable leads to decreases in the other. Ex: As tooth brushing goes up, tooth decay goes down

Some More Correlation Examples Married people tend to have higher measures of happiness. Children who watch high amounts of television are more aggressive. People with low self-esteem are more likely to be depressed. What meanings can we make of these examples?

Correlations Continued Correlation Coefficient: the statistical measure of the extent to which two factors vary together and thus how well either factor predicts the other. (number that measures strength of the correlation). STRONGEST CORRELATIONS are +1 and –1. +1 is a perfect positive correlation while –1 is a perfect negative correlation. Correlations are always between –1 and +1. A correlation of Zero means there is no relationship.

Correlation Scatterplots Perfect positive correlation (+1.00) No relationship (0.00)Perfect negative correlation (-1.00)

Indicates strength of relationship (0.00 to 1.00) Correlation coefficient Indicates direction of relationship (positive or negative) r = +.37

R=+.37 R=-1.00 R=+.17 R= -.08

Correlation Measures 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

Temperament scores Height in inches

Height and Temperament of 20 Men Subject Height in Inches Temperament Subject Height in Inches Temperament

Correlation and Causation Correlation does not prove causation Ex- negative correlation between self-esteem and depression – Heredity and brain chemistry might play a role Among men, length of marriage correlates positively with hair loss- because both are associated with a third factor. – Age – Correlation indicates the possibility of a cause and effect relationship, but DOES NOT prove causation

Intuition Limit #976 Illusory Correlation: the perception of a relationship where none exists. Sugar makes kids more hyperactive Wet hair and cold hair cause a cold Don’t overgeneralize extreme cases GET THE DATA!!

One last check…………….. You need to make sure your study is reliable and valid. 1.Reliability-if your study was replicated would you get the same results? 2.Validity- Does the study or experiment test what it is designed to test.

Summing Up Surveys, Naturalistic Observation, Case Studies, and Correlation Research All of these methods look to describe the behavior not to explain it! Experimental Designed research is the only research that gets at causation!

Random Sequences z zYour chances of being dealt either of these hands is precisely the same: 1 in 2,598,960.

Experimentation and Statistics

Experiments

Experimentation Experiments are the best way to isolate cause and effect – the investigator manipulates one or more factors (independent variables) to observe their effect on some behavior or mental process (the dependent variable) while controlling other relevant factors by random assignment of subjects – by random assignment of participants the experiment controls other relevant factors. Breast Milk Example

Experimentation Research Strategies Double-blind Procedure – both the subject and the research staff are ignorant (blind) about whether the subject has received the treatment or a placebo – commonly used in drug-evaluation studies Placebo – an inert substance or condition that may be administered instead of a presumed active agent, such as a drug, to see if it triggers the effects believed to characterize the active agent Placebo Effect- the effect of positive thought and willpower on an experiment

Experimentation Research Strategies Experimental Condition – The group that is exposed to the treatment, that is, to one version of the independent variable ( real drug) Control Condition – The group that contrasts with the experimental treatment. Get the placebo, or possible nothing – serves as a comparison for evaluating the effect of the treatment Example- Viagra

Experimentation Research Strategies Random Assignment – assigning subjects to experimental and control conditions by chance – minimizes pre-existing differences between those assigned to the different groups – Want similar age, attitudes…….

Experimentation Research Strategies Independent Variable – the experimental factor that is manipulated – the variable whose effect is being studied 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 – It can vary depending on what happens during the experiment Cause/effect…… If/Then

Experimentation Confounding Variables- – Variables that cause changes in the DV besides the IV Breast Feeding Example Operational Definitions – Example Viagra IV- Viagra or placebo- time, amount DV- Sex- ………………………..

Experimentation Problems- Sometimes not feasible or ethical 1. Obtain consent 2. Protect from harm 3. Confidential 4. Fully explain research after the exp. Animals? Results may not overgeneralize to other contexts

Statistics

Describing Data Researchers first need to organize their data Pie Chart, Bar graph Descriptive Statistics- describe the data, but don’t focus or the relationship

Our Brand Brand Brand Brand X Y Z 100% Percentage still functioning after 10 years Brand of truck

Our Brand Brand Brand Brand X Y Z 100% Percentage still functioning after 10 years Brand of truck

Measure of Central Tendency 3 measures of Central Tendency- Mode, Mean and Median Mode- the most frequently occurring score Mean- average Median- the middle score, when you arrange the score in order from the highest to lowest Be Careful- can a few extreme score through off any one of the central tendencies? What's wrong with- income for 62% is below average

Mode Median Mean One Family Income per family in thousands of dollars

Measures of Variation Need to know the variation in the data, how diverse or similar the scores are Range– the gap between the highest and lowest score Remember extremes scores can skew the data 475,000 and 710,000

Measures of Variation The more useful measure is Standard Deviation – It gauges if scores are packed together or dispersed – Uses info from each score – Smaller Standard Deviation for more similar populations – Higher Standard Deviation for more diverse populations

When is an Observed Difference Reliable? 1. Representative samples are better than biased samples 2. Less variable observations are more reliable than those that are more variable Consistency 3. More Cases Are better than few

When is Difference Significant? statistical significance (p) is a measure of the likelihood that the difference between groups results from a real difference between the 2 groups rather than from chance If statistically significant …..the differences are probably not due to chance Statistical significance indicates the likelihood that a result will happen by chance. It does not indicate the importance of the result The lower the P value, the less likely the results are due to chance (P<.o1)