General Psychology 2301 Research Methods and Scientific Foundation Notes

The Scientific Approach & Psychology as a Science

• Definition of Science: Science is the use of systematic observation in order to acquire knowledge. It is not merely a collection of isolated facts or general knowledge; rather, it represents the structured process through which knowledge is acquired and tested.

• Impact of Scientific Inquiry: Modern technological and medical advances exist due to the scientific method. Critical developments driven by science include:

  • Electricity

  • Telephones and mobile phones

  • Refrigeration

  • Antibiotics

  • Birth control

  • Television

  • Increased life expectancy

  • Improved nutrition

• Four Key Characteristics of the Scientific Approach:

  • Systematic Observation: Organized and structured observation where researchers measure phenomena, record observations, attempt to control conditions, systematically vary conditions, and look for consistent patterns. The objective is to minimize the influence of memory limitations, personal expectations, and subjective cognitive biases on conclusions.

  • Testable Hypotheses: Scientific questions and hypotheses must be empirically testable. For example, testing whether paraffin candles burn more slowly than identical beeswax candles by systematically lighting both types and measuring burn duration.

  • Democratic Nature: Scientific authority does not rely on claims of personal expertise (e.g., "I am an expert, therefore I am right"). Instead, conclusions are open to public debate, scientists publish competing findings, evaluate empirical evidence, and allow evidence to determine conclusions.

  • Cumulative Knowledge: Science builds incrementally upon past discoveries. For instance, high school and college students today can know more about physics than Isaac Newton did because modern scientific understanding accumulates over generations.

• Operationalizing Unobservable Psychological Constructs:

  • Psychology studies mental states and internal experiences that cannot always be seen directly. To study these scientifically, researchers create operational definitions to measure invisible constructs objectively.

  • Example methods for operationalizing depression:

  • Self-report surveys and questionnaires

  • Clinical diagnostic rating scales

  • Direct behavioral observations

  • Informant reports from friends or family members

  • Cognitive memory performance measures

  • Biological measures (e.g., brain imaging, neurotransmitter levels, hormone assays)

• Real-World Contributions of Psychological Subfields:

  • Clinical Psychology: Developed empirical treatments, including Cognitive Behavioral Therapy (CBT) for depression and anxiety.

  • Industrial/Organizational (I/O) Psychology: Implemented workplace interventions that increase employee productivity, performance, and job satisfaction.

  • Human Factors: Redesigned aircraft cockpit controls and instrument layouts, reducing pilot confusion and operational errors.

  • Forensic Psychology: Research led by Elizabeth Loftus demonstrated significant limitations and vulnerabilities in eyewitness memory and legal testimony.

Ethical Principles in Psychological Research

• Core Ethical Standards:

  • Informed Consent: Human participants must understand that they are participating in research, be fully informed of what will happen during the study, and participate voluntarily with the freedom to withdraw at any time.

  • Confidentiality: Personal participant information and response data must not be made public without explicit written consent.

  • Privacy: Researchers must respect private boundaries and spaces (e.g., avoiding unauthorized surveillance in private settings).

  • Benefits vs. Risks: Researchers must perform a risk-benefit analysis to ensure potential societal and scientific benefits outweigh potential physical or psychological risks to participants.

  • Deception and Debriefing: When temporary deception is necessary to prevent participant bias, subjects must receive a complete debriefing after the study to learn the true nature of the research, the hypotheses, and why deception was used.

• Ethical Evaluation of Research Scenarios:

  • Public Criticism Study: Publicly criticizing participants in class without prior warning violates informed consent, causes severe psychological harm, and fails the risk-benefit standard (Status: Reject or Modify).

  • Secret Phone Recording: Secretly recording private student conversations violates privacy, confidentiality, and informed consent standards (Status: Reject or Modify).

  • Stressful Task Study: Informing participants beforehand that a task may cause stress and providing them the option to stop at any time satisfies informed consent and voluntary participation (Status: Approve).

  • Deception Study: Deceiving participants about a study's actual purpose followed immediately by a complete debriefing session adheres to ethical requirements (Status: Approve).

Variables and Core Concepts in Research Design

• Core Variable Definitions:

  • Independent Variable (IV): The variable that the researcher directly manipulates, changes, or controls.

  • Operational Rule: "IV = I change it."

  • Dependent Variable (DV): The outcome variable that the researcher measures to observe the effect of the independent variable; it is not manipulated.

  • Operational Rule: "DV = Data I collect."

  • Example: Investigating whether sleep affects test performance:

  • IV: Amount of sleep (e.g., 8 hours vs. 4 hours).

  • DV: Test performance score.

• Identifying Independent and Dependent Variables in Practice:

  • Music and Exam Performance: IV = Listening to music while studying; DV = Exam performance score.

  • Exercise and Stress: IV = Exercise level/duration; DV = Measured stress level.

  • Social Media Use and GPA: IV = Time spent on social media; DV = Grade Point Average (GPA).

• Threats to Research Validity and Common Methodology Problems:

  • Participant Demand: Occurs when participants guess the researcher's hypothesis and alter their natural behavior to match what they believe is expected of them.

  • Experimenter Expectations: Occurs when a researcher's subconscious cues, expectations, or biases influence participant behavior or outcome measurement.

  • Placebo Effect: Occurs when participants experience real physical or psychological changes simply because they believe they are receiving a special treatment or intervention.

  • Confounding Variables (Confounds): Extraneous factors that systematically co-vary with the independent variable, making it impossible to determine whether the IV or the extraneous factor caused the observed changes in the DV.

  • Example: Tutoring and high grades. A student's internal motivation could drive both attendance in tutoring and higher grades, serving as a confound.

Types of Research Designs

• Experimental Research:

  • Definition: A research method in which the investigator manipulates an independent variable and uses random assignment to evaluate its causal effect on a dependent variable.

  • Core Requirements: Independent variable, dependent variable, experimental manipulation, and random assignment.

  • Importance of Random Assignment: Participants are assigned to experimental or control groups purely by chance. This equalizes preexisting participant differences across conditions (e.g., baseline intelligence, motivation). Self-selection into groups introduces bias and prevents causal conclusions.

  • Example: Assigning students randomly to study in quiet environments versus listening to music, followed by an evaluation of test performance.

• Correlational Research:

  • Definition: Measures the naturally occurring statistical relationship between two or more variables without manipulating them.

  • Fundamental Limitation: Correlation does not establish causation ($\text{Correlation} \neq \text{Causation}$).

  • Three Causal Possibilities for Any Correlation between Variable A and Variable B:

  1. Direction 1: Variable A causes Variable B ($A \rightarrow B$).

  2. Direction 2: Variable B causes Variable A ($B \rightarrow A$).

  3. Third Variable Problem: An unmeasured third variable ($C$) causes both Variable A and Variable B ($C \rightarrow A$ and $C \rightarrow B$).

  • Example: Generosity and happiness are positively correlated.

  • Possibility 1: Generosity causes happiness ($\text{Generosity} \rightarrow \text{Happiness}$).

  • Possibility 2: Happiness causes generosity ($\text{Happiness} \rightarrow \text{Generosity}$).

  • Possibility 3: Wealth causes both ($\text{Wealth} \rightarrow \text{Generosity}$ and $\text{Wealth} \rightarrow \text{Happiness}$).

• Quasi-Experimental Design:

  • Definition: A research design that compares existing pre-formed groups or conditions without utilizing random assignment.

  • Usage: Applied when variable manipulation or random assignment is impossible or unethically prohibitive (e.g., comparing married vs. unmarried individuals, comparing existing classrooms).

  • Limitation: Inferring causation is difficult due to baseline differences and self-selection bias.

  • Example: Comparing test scores of students enrolled in Professor Smith's course section versus Professor Khan's course section.

• Qualitative Research:

  • Definition: Research methods focused on exploring detailed, non-numerical experiences, perspectives, and contexts.

  • Three Key Qualitative Approaches:

  1. Participant Observation: The researcher immerses themselves in a group or environment to observe behavior firsthand.

  2. Case Study: An intensive, in-depth empirical examination of a specific individual, group, or context.

  3. Narrative Analysis: The systematic study of personal stories, testimonies, and verbal accounts.

  • Causation: Cannot establish causation.

• Longitudinal Research:

  • Definition: A design that tracks and tests the same sample of participants repeatedly over an extended period of time.

  • Example: Measuring student stress levels sequentially during their freshman year, junior year, and senior year of college.

  • Strengths and Weaknesses: Excellent for measuring individual developmental changes over time; however, it requires significant time, financial resources, and carries participant attrition risks (loss of subjects over time). Time elapsed alone does not establish causation.

• Research Design Cheat Sheet:

Applied Methodology Exercises and Case Solutions

• Evaluating Causal Claims (In-Class Activity #3):

  • Claim: "Students who spend more time studying tend to have higher GPAs."

  • Evaluation: Correlation Only. Causation cannot be stated because third variables like study efficiency, baseline intelligence, or motivation could drive both study time and higher GPAs.

  • Claim: "People who exercise more report lower stress."

  • Evaluation: Correlation Only. Lower baseline stress could provide people with more free time and energy to exercise.

  • Claim: "People who own more books tend to have higher incomes."

  • Evaluation: Correlation Only. Socioeconomic status and household disposable income drive book purchases and income levels simultaneously.

• Selecting Appropriate Research Designs (In-Class Activity #4):

  • Question 1: "Does caffeine improve reaction time?"

  • Selected Design: Experimental Design (manipulate caffeine vs. placebo, randomly assign participants, measure reaction time in milliseconds).

  • Question 2: "Are people who exercise more less stressed?"

  • Selected Design: Correlational Design (survey individuals regarding weekly exercise duration and administer a standardized stress scale).

  • Question 3: "Does marriage affect happiness?"

  • Selected Design: Quasi-Experimental Design (compare pre-existing groups of married vs. unmarried individuals on happiness metrics).

  • Question 4: "How does a person experience life after losing a spouse?"

  • Selected Design: Qualitative Design (conduct in-depth case studies or narrative analysis interviews with grieving spouses).

  • Question 5: "How does happiness change over the course of adulthood?"

  • Selected Design: Longitudinal Design (follow a cohort of adults across several decades, measuring happiness periodically).

• Identifying Research Problems in Practice (In-Class Activity #5):

  • Scenario A: A researcher gives unintentionally positive feedback during interviews to participants who received a new therapy.

  • Identified Problem: Experimenter Expectations.

  • Scenario B: Participants deduce that researchers want them to exercise more, so they over-report their physical activity.

  • Identified Problem: Participant Demand.

  • Scenario C: Participants report feeling better simply because they believe they received a new medical treatment.

  • Identified Problem: Placebo Effect.

  • Scenario D: Students who voluntarily sign up for a study-skills program earn higher grades than those who do not.

  • Identified Problem: Confounding Variables (e.g., student motivation, self-discipline).

• Step-by-Step Research Study Design Protocol:

  1. Formulate Hypothesis: Define a testable prediction regarding cause and effect or association.

  2. Define Independent Variable: Specify the exact manipulation and control conditions.

  3. Define Dependent Variable: Select the quantitative metric to collect.

  4. Select Research Design: Choose experimental, correlational, quasi-experimental, qualitative, or longitudinal methodology based on ethical and logistical feasibility.

  5. Operationalize Variables: Specify measurement tools (e.g., surveys, physiological equipment, cognitive testing).

  6. Determine Participant Assignment: Utilize random assignment whenever experimental designs are used.

  7. Identify and Control Confounds: Anticipate extraneous variables and control them experimentally or statistically.

  8. Address Threats to Validity: Prevent participant demand, experimenter bias, and placebo effects through double-blind procedures and standardized instructions.

Exit Ticket Review and Study Questions

• Question 1: In your own words, what makes psychology a science?

  • Answer: Psychology is a science because psychologists utilize systematic observation, testable hypotheses, operational definitions, controlled experimentation, and empirical data collection to formulate and test explanations of human behavior and mental processes.

• Question 2: What is the difference between an independent variable and a dependent variable?

  • Answer: An independent variable (IV) is manipulated and controlled directly by the researcher, whereas a dependent variable (DV) is measured by the researcher to determine the outcome or effect of that manipulation.

• Question 3: Why cannot a correlation by itself establish causation?

  • Answer: A correlation establishes only that two variables are associated. It does not clarify directionality ($A \rightarrow B$ vs. $B \rightarrow A$) and cannot eliminate the potential influence of unmeasured third variables (confounds) that cause both variables to change.

• Question 4: Name one ethical principle that researchers must follow, and explain why it is important.

  • Answer: Informed consent requires that participants voluntarily agree to participate after being fully informed about the study's procedures and risks, thereby safeguarding individual autonomy and safety.

• Question 5: Give one situation where a researcher might choose a quasi-experimental, qualitative, or longitudinal design instead of an experiment.

  • Answer: A researcher would choose a quasi-experimental design when studying variables that cannot be ethically or practically manipulated (e.g., comparing married vs. unmarried people, or individuals with brain injury). A qualitative design is chosen when deep, detailed personal descriptions of lived experiences are needed (e.g., adjusting to spousal loss). A longitudinal design is selected when tracking individual development or cognitive trajectories across time.