Psychology - Research

Common Questions, Beliefs, and Myths

  • What people often think vs. what scientific evidence suggests

  • Page 3: The belief that we use 10% of our brain (myth or misconception to be tested scientifically)

  • Page 4: Intuition on MC exams—initial gut responses vs. evidence-based strategies

  • Page 5: The belief that opposites attract in relationships

Science and Skepticism in Psychology

  • Evaluating beliefs requires scientific research to avoid relying on intuition, authority, luck, or personal experience alone

  • The scientific method uses: careful evidence collection, formulation of hypotheses, and theory-based evaluation

  • Key attitude: be skeptical and demand evidence

Key Concepts: Theory and Hypothesis

  • Theory: An organized system of statements that explains when, how, and why some phenomena occur

  • Hypothesis: A clear predictive statement/general premise/idea; can be based on intuition, observation, or better, theory

  • Example: Hypothesis — Watching violent TV shows makes people aggressive

    • Question: How do you test this? (introduces empirical testing)

The Cycle of Science

  • Hypothesis/idea → empirical observations → Results → Supported/Not supported

Reasoning in Psychology: Deductive vs Inductive

  • Deductive reasoning

    • Start with an idea or hypothesis and test it against the real world

    • Largely used in psychology; conclusions flow from theories

  • Inductive reasoning

    • Start with observations and generalize from them

    • Example given: dog barks before dinner → assumes all dogs bark when hungry (a generalization that may be flawed)

Fallacies in Inductive Reasoning

  • Just because we observe a pattern doesn’t guarantee the conclusion is valid

  • Example: You loved The Matrix → Keanu Reeves is in The Matrix → Keanu Reeves is in Speed → Conclusion: You will like Speed

  • What’s wrong: Drawing a conclusion from a chain of observations without a solid logical link or sufficient data

Affirming the Consequent (Fallacy)

  • If you live in Brooklyn, then you live in New York

  • You live in New York

  • Therefore, you must live in Brooklyn

  • Note: This is a logical fallacy; correlation or co-occurrence does not imply causation or the exact conditional relationship

Testing Our Theories: Complexity and Multiple Explanations

  • Behaviors are complex; more than one theory can explain results

  • Sometimes more than one theory can predict the same outcomes

Multiple Theories and Phenomena

  • Phenomena can be consistent with Theory 1 and Theory 2 simultaneously

  • Illustration: Theory 1 vs Theory 2 with shared predictions (Prediction 1)

  • Testing: Confirming Prediction 1 corroborates both theories

Falsification and Revision in Theory Testing

  • Falsification: If a prediction is contradicted by evidence, the theory can be falsified

  • Example structure: If Prediction 1 is false, Theory 1 is falsified; Theory 2 remains viable if its predictions hold

  • Revision: Update wrong theories with new assumptions to better predict new evidence

Newer Tests and Generating New Predictions

  • Look for differences in the assumptions between theories to generate new predictions

  • Combine theories or introduce new ideas to create Prediction 1, Prediction 2, Prediction 3, etc.

Survival of the Fittest: Competing Theories

  • When several theories can explain phenomena, evaluate by generating new, testable predictions

  • More than one theory may survive if they withstand empirical testing

Parsimony: Simpler Explanations First

  • Parsimony principle: Prefer explanations with fewer, simpler, or more coherent assumptions when facts fit multiple explanations

  • Sometimes the simplest explanation is the best

Can You Read My Mind? Cognitive Biases in Prediction

  • Activity: A number between 1 and 50 with constraints (both digits odd, distinct)

  • Demonstrates how people infer patterns and search for structure with limited information

  • Highlights human tendency to impose patterns even with minimal data

Did You Read My Mind? Interpreting Ambiguity in Choices

  • You have many options (1–50) but constraints steer choices

  • People often infer probable choices (e.g., 37 is most likely, 35 follows) based on heuristics

What’s Going On Here? Mind Reading and Beating the Odds

  • Link to Derren Brown video: https://www.youtube.com/watch?v=sEmCQzueyEQ&ab channel=Derren Brown

  • Demonstrates psychology of prediction, suggestion, and cognitive biases

Paranormal Activity and Skepticism

  • No laboratory evidence, non-replicable results for paranormal claims

  • When unusual events occur, consider alternative explanations; controlled studies are needed to advance science

Research Methods: Overview and Options

  • Naturalistic observation

  • Surveys

  • Archival research

  • Longitudinal & Cross-Sectional designs

  • Correlational studies

  • Experiments (lab and field)

  • All are tools to study behavior and mental processes

Naturalistic Observation

  • Observing behavior in natural settings (e.g., do people wave and thank when cars let them cross the street?)

Pros of Naturalistic Observation

  • Captures behavior in real-world settings

  • Ecological validity can be higher than lab settings

  • Less artificial; cheaper; potentially greater external validity

  • Fewer ethical concerns in some contexts

Cons of Naturalistic Observation

  • Lack of control over extraneous variables

  • Risk of observer bias

  • Time-consuming

  • Cannot prove causality

Surveys: What They Do

  • Questionnaires to collect attitudes, beliefs, preferences, behaviors in a population

  • Examples: voting, customer experience, polling

Issues with Surveys

  • Representativeness and sample size affect conclusions

  • Social desirability bias: respondents give desirable answers

  • Inattention: use attention checks to ensure data quality (Aust et al., 2013)

Attention Checks in Surveys

  • Where to place attention check? Beginning, end, or throughout

  • Referenced work: Oppenheimer et al., 2009

  • Example items include intrusive or clearly off-topic questions to detect inattention

Examples of Survey Items and Biases

  • Example 1: I oppose raising taxes (1 = strongly disagree, 7 = strongly agree)

  • Example 2: I make it a practice to never lie (1 = strongly disagree, 7 = strongly agree)

  • Example 3: I would be willing to pay extra taxes for high-quality education (1 = strongly disagree, 7 = strongly agree)

  • Example 4: Like all humans, I occasionally tell a lie (1 = strongly disagree, 7 = strongly agree)

  • Exercise: Raise your hand if your score on all four questions is greater than 4

Leading Questions and Biases in Surveys

  • Biased phrasing can influence responses

  • Examples: "How satisfied are you with our product?" vs. "How do you think the new policies are?"

  • Encourages respondents to think in a particular direction

Correlational Research: What It Measures

  • Correlation = measure of the association between two variables

  • Examples: height and weight; personality score and number of friends

  • Correlational research examines association without manipulating variables

  • The correlation coefficient r ranges between -1 and +1 and indicates strength and direction

  • Mathematical expression (concept): r=raccov(X,Y)sd(X)sd(Y)r = rac{cov(X,Y)}{sd(X) \, sd(Y)}

Scatterplots: Visualizing Correlations

  • Illustrates the relationship between two variables (e.g., study performance vs. prior test score; absences vs. scores)

  • Helps identify direction (positive/negative) and strength of association

Correlation Does Not Imply Causation

  • Example: Nobel Laureates per 10M people vs. chocolate consumption shows a correlation but does not imply causation

  • Key idea: A third variable can drive the observed association

  • Common third-variable examples: GDP, temperature (as a third variable influencing crime, ice cream sales, etc.)

Try This: Sleep and Mortality Association

  • Finding: People sleeping ~7 hours/night have lower mortality risk than those sleeping more or less

  • Important caveat: Does sleep cause lower mortality? Consider reverse causation (existing illnesses increase sleep) and third-variable explanations

Alternative Explanations and Causality Challenges

  • Example: Sleep and health may be confounded by existing illnesses

  • Example: Spanking and child misbehavior — correlation does not imply spanking causes misbehavior; alternative explanations include reverse causation and hereditary factors (Larzelere, Kuhn, & Johnson, 2004)

Illusory Correlation

  • Tendency to perceive a relationship between two variables where none exists when data are unsystematic

  • Example: Sugar intake causing hyperactivity in children

Explanations for Illusory Correlations

  • Early studies suggested sugar reduces behavior, but biases and expectations affected observations (Milich, Wolraich, & Lindgren, 1986; Wolraich et al., 1994)

  • Mothers’ expectations led to biased ratings (Hoover & Milich, 1994)

Experiments: The Gold Standard for Causality

  • Definition: A study where you manipulate at least one variable and measure at least another

  • Examples: Angry people lie more than non-angry people; performance differences in lit vs. dark room

Key Experimental Terms

  • Independent Variable (IV): what you manipulate

  • Dependent Variable (DV): what you measure; changes due to IV

  • Control Group vs. Experimental Group: no treatment vs. received treatment

  • Random Assignment: each participant has equal probability of assignment to groups

  • Operational Definition: how a variable is measured or manipulated

Biases in Experiments

  • Experimenter bias: researcher expectations influence the outcome

  • Demand characteristics: clues about the study shape participant behavior

  • Good participant/Good subject role: participants respond in a way that pleases the experimenter

  • Negative subject role: participants respond in a way that disappoints the expectations

Reducing Biases in Research

  • Single-blind design: participants do not know which group they are in, but researchers do

  • Double-blind design: neither researchers nor participants know group assignments

  • These designs control for expectancy effects and reduce demand characteristics

Techniques to Reduce Bias: Summary

  • Implement single-blind or double-blind protocols where possible

  • Use standardized procedures and objective measures

  • Pre-register hypotheses and analysis plans to reduce flexible post hoc reasoning

  • Use random assignment to equalize groups on confounding variables

  • Employ control groups to establish a baseline

Practical Takeaways for Research in Psychology

  • Be skeptical of intuitive or surface-level patterns; seek empirical validation

  • Recognize that multiple theories can explain a phenomenon; test predictions to differentiate them

  • Use parsimony to prefer simpler, well-supported explanations when evidence is equivalent

  • Distinguish correlation from causation; consider third variables and experimental manipulation to establish causality

  • Understand and mitigate biases through rigorous design (blind designs, randomization) and robust measurement

  • Choose appropriate methods for the research question (naturalistic observation, surveys, archival data, longitudinal vs cross-sectional, correlational, experiments)

Notable Examples and References from the Slides

  • 10% brain myth (Page 3) – a classic misconception often challenged by neuroscience research

  • Initial intuition in multiple-choice exams (Page 4) – caveat against sticking to first gut answer without evidence

  • Opposites attract (Page 5) – common relationship belief; empirical evidence often shows complexity

  • Derren Brown video reference (Page 24) – media example illustrating mind-reading tricks and cognitive biases

  • Kripke et al. sleep study (Page 42) – sleep duration and mortality association; emphasizes critical interpretation

  • Oppenheimer et al. (2009) on attention checks (Page 32) – importance of attention checks in surveys

  • Milich, Wolraich, & Lindgren (1986); Wolraich et al. (1994); Hoover & Milich (1994) – sugar and hyperactivity studies and bias considerations

  • Larzelere, Kuhn, & Johnson (2004) – alternative explanations for spanking and child behavior

  • Messerli (2012) – Nobel laureates vs. chocolate consumption correlation (Figure 1)

Key Formulas and Concepts (Summary)

  • Correlation coefficient: r=raccov(X,Y)sd(X)sd(Y)extwithrextin[1,1]r = rac{cov(X,Y)}{sd(X)\,sd(Y)} ext{ with } r ext{ in } [-1,1]

  • Experimental design basics:

    • Independent variable: manipulated

    • Dependent variable: measured

    • Random assignment: equal probability to groups

    • Operational definition: how variables are measured

  • Causation vs correlation: presence of correlation does not imply causation; third variables can explain associations

  • Parsimony: prefer simpler explanations when data fit multiple theories

  • Bias reduction: single-blind, double-blind techniques to control for expectations and demand characteristics