PSYC 100: Introduction to Psychology
Week 1 Supplement Part 2
Dr. Carlyle Rogers, Associate Professor
Psychological Research
Research is fundamental in psychology for several key reasons:
Advancing Knowledge
Evidence-Based Practice
Validating Interventions
Understanding Diversity
Informing Policy
Improving Education
Personal and Social Impact
Bridging Gaps
Ethical Standards
Innovation
In psychology, theories and hypotheses are fundamental components of the scientific method. They play crucial roles in guiding research and understanding psychological phenomena.
Theory
Examples
Hypothesis
Types
Examples
In summary, a theory in psychology is a broad, evidence-based framework that explains and predicts various psychological phenomena, while a hypothesis is a specific, testable prediction derived from a theory. Hypotheses are used to conduct empirical research, which in turn helps to support, refine, or challenge existing theories.
Conducting psychological research involves several important aspects and terminology that are essential for understanding and executing scientific studies effectively.
Research Design
Ethics
Sampling
Data Collection Methods
Data Analysis
Validity and Reliability
Hypotheses
Variables
Operationalization: Defining how variables will be measured or manipulated in the study.
Random Assignment: Assigning participants to experimental and control groups by chance, minimizing pre-existing differences.
Control Group: The group that does not receive the experimental treatment, used for comparison.
Experimental Group: The group that receives the treatment or intervention.
Placebo: A substance or treatment with no active therapeutic effect, used as a control in experiments.
Double-Blind Study: Both the participants and the researchers do not know who is receiving the treatment or placebo, reducing bias.
Statistical Significance: A measure of whether the results are likely due not to chance. Commonly denoted by a p-value (e.g., p < 0.05).
In psychology, correlation refers to a statistical measure that describes the extent to which two variables are related to each other.
Correlation
Positive Correlation
Negative Correlation
Key Points
Understanding correlations is important in psychology as it helps researchers identify patterns and relationships between different variables, which can lead to further investigation and understanding of underlying mechanisms.
Research is fundamental in psychology for several key reasons:
Advancing Knowledge
- Understanding Behavior: Research helps to uncover the underlying mechanisms of thoughts, emotions, and behaviors.
- Theoretical Development: It contributes to the development and refinement of psychological theories and models.
Evidence-Based Practice
- Informing Treatment: Research provides the evidence needed to develop and implement effective therapeutic interventions and treatments.
- Best Practices: It identifies best practices and guidelines for clinical practice, education, and policy.
Validating Interventions
- Efficacy and Effectiveness: Research tests the efficacy and effectiveness of various psychological interventions and therapies, ensuring they work as intended.
- Safety: It ensures that interventions are safe and do not cause harm.
Understanding Diversity
- Cultural Relevance: Research helps to understand how psychological phenomena differ across cultures, ages, genders, and other demographic variables.
- Inclusive Practices: It promotes the development of inclusive practices that consider diverse populations.
Informing Policy
- Public Health: Research informs public health policies and programs aimed at improving mental health at the population level.
- Legislation: It provides the data needed to support mental health legislation and funding decisions.
Improving Education
- Educational Strategies: Research identifies effective educational strategies and teaching methods.
- Student Outcomes: It helps improve student outcomes by understanding factors that influence learning and development.
Personal and Social Impact
- Individual Well-being: Research helps individuals understand themselves better and improve their personal well-being.
- Social Issues: It addresses social issues such as prejudice, discrimination, and violence, contributing to social change.
Bridging Gaps
- Theory-Practice Gap: Research bridges the gap between theoretical knowledge and practical application, ensuring that psychological practices are grounded in scientific evidence.
- Interdisciplinary Collaboration: It fosters interdisciplinary collaboration, integrating insights from other fields such as neuroscience, medicine, and sociology.
Ethical Standards
- Ethical Guidelines: Research contributes to the development of ethical guidelines and standards for conducting psychological research and practice.
- Protecting Participants: It ensures that research participants are protected and treated ethically.
Innovation
- New Technologies: Research drives the development of new technologies and methodologies in psychological assessment and treatment.
- Creative Solutions: It fosters innovative approaches to solving psychological problems and improving mental health care.
In psychology, theories and hypotheses are fundamental components of the scientific method. They play crucial roles in guiding research and understanding psychological phenomena.
Theory
- Definition: A theory is a well-substantiated, comprehensive explanation of an aspect of the natural world that is based on a body of evidence. It integrates and explains a wide range of observations and findings.
- Purpose: Theories help to organize and make sense of existing knowledge. They provide a framework for understanding how different psychological phenomena are related and guide future research by generating new hypotheses.
- Broad Scope: Theories cover a wide range of phenomena and are applicable in various situations.
- Evidence-Based: Theories are supported by a substantial amount of empirical evidence.
- Predictive Power: Theories offer predictions about future events or behaviors, which can be tested through research.
- Falsifiability: Theories should be able to be tested and potentially disproven through empirical observation and experimentation.
Examples
- Cognitive Dissonance Theory: Proposes that people experience psychological discomfort when they hold conflicting beliefs or behaviors and are motivated to reduce this discomfort by changing their attitudes or behaviors.
- Attachment Theory: Suggests that early relationships with caregivers shape an individual's patterns of attachment and influence their emotional development and relationships throughout life.
Hypothesis
- Definition: A hypothesis is a specific, testable prediction derived from a theory. It proposes a relationship between two or more variables.
- Purpose: Hypotheses are used to guide empirical research. They provide a focused question that researchers can test through observation and experimentation.
- Specificity: Hypotheses are specific statements about the expected relationship between variables.
- Testability: Hypotheses must be formulated in a way that allows them to be tested empirically.
- Falsifiability: Hypotheses should be structured so that they can be proven wrong if the evidence contradicts them.
Types
- Null Hypothesis (H0): A statement that there is no effect or no relationship between variables. It serves as the default position that researchers aim to test against.
- Alternative Hypothesis (H1): A statement that there is an effect or a relationship between variables. It represents the researcher's actual prediction.
Examples
- Hypothesis from Cognitive Dissonance Theory: "People who are paid a small amount of money to perform a boring task will report enjoying the task more than those who are paid a large amount of money."
- Hypothesis from Attachment Theory: "Children with secure attachments to their caregivers will show lower levels of anxiety in new social situations compared to children with insecure attachments."
In summary, a theory in psychology is a broad, evidence-based framework that explains and predicts various psychological phenomena, while a hypothesis is a specific, testable prediction derived from a theory. Hypotheses are used to conduct empirical research, which in turn helps to support, refine, or challenge existing theories.
Conducting psychological research involves several important aspects and terminology that are essential for understanding and executing scientific studies effectively.
Research Design
- Experimental Design: Involves manipulation of independent variables to observe their effect on dependent variables. Includes control groups, random assignment, and controlled conditions.
- Correlational Design: Examines the relationship between two or more variables without manipulating them. Determines whether an association exists.
- Longitudinal Design: Studies the same participants over an extended period to observe changes and developments.
- Cross-Sectional Design: Compares different groups of participants at a single point in time.
Ethics
- Informed Consent: Participants must be fully informed about the study and voluntarily agree to participate.
- Confidentiality: Participants' data must be kept private and used only for the purposes of the research.
- Deception: If used, it must be justified and participants must be debriefed afterwards.
- Institutional Review Board (IRB): A committee that reviews research proposals to ensure ethical standards are met.
Sampling
- Population: The entire group of individuals the research is interested in.
- Sample: A subset of the population selected for the study.
- Random Sampling: Every individual in the population has an equal chance of being selected.
- Convenience Sampling: Participants are selected based on availability and willingness to take part.
Data Collection Methods
- Surveys/Questionnaires: Structured forms of collecting self-reported data from participants.
- Interviews: In-depth, often face-to-face, conversations to gather detailed information.
- Observations: Recording behaviors and events in natural or controlled settings.
- Experiments: Controlled investigations to test hypotheses by manipulating variables.
Data Analysis
- Descriptive Statistics: Summarize and describe data (e.g., mean, median, mode, standard deviation).
- Inferential Statistics: Make inferences about the population based on sample data (e.g., t-tests, ANOVA, regression analysis).
Validity and Reliability
- Validity: The extent to which a test measures what it claims to measure.
- Internal Validity: The degree to which the results can be attributed to the manipulated variables rather than other factors.
- External Validity: The extent to which the results can be generalized to other settings and populations.
- Reliability: The consistency of a measure. A reliable test yields the same results under consistent conditions.
Hypotheses
- Null Hypothesis (H0): A statement that there is no effect or difference. It is what the researcher tries to disprove.
- Alternative Hypothesis (H1): A statement that there is an effect or difference. It is what the researcher aims to support.
Variables
- Independent Variable (IV): The variable that is manipulated by the researcher to observe its effect.
- Dependent Variable (DV): The variable that is measured to see the impact of the IV.
- Confounding Variables: Variables other than the IV that may affect the DV, potentially skewing results.
Operationalization: Defining how variables will be measured or manipulated in the study.
Random Assignment: Assigning participants to experimental and control groups by chance, minimizing pre-existing differences.
Control Group: The group that does not receive the experimental treatment, used for comparison.
Experimental Group: The group that receives the treatment or intervention.
Placebo: A substance or treatment with no active therapeutic effect, used as a control in experiments.
Double-Blind Study: Both the participants and the researchers do not know who is receiving the treatment or placebo, reducing bias.
Statistical Significance: A measure of whether the results are likely due not to chance. Commonly denoted by a p-value (e.g., p < 0.05).
In psychology, correlation refers to a statistical measure that describes the extent to which two variables are related to each other.
Correlation
- Definition: Correlation measures the strength and direction of the relationship between two variables.
- Correlation Coefficient (r): A numerical value ranging from -1 to +1 that indicates the strength and direction of the relationship.
- +1: Perfect positive correlation.
- -1: Perfect negative correlation.
- 0: No correlation (no relationship between the variables).
Positive Correlation
- Definition: A positive correlation occurs when an increase in one variable is associated with an increase in another variable.
- Example: If study time and test scores have a positive correlation, as the amount of time spent studying increases, test scores tend to increase as well.
- Interpretation: Both variables move in the same direction. When plotted on a scatterplot, the data points slope upward from left to right.
Negative Correlation
- Definition: A negative correlation occurs when an increase in one variable is associated with a decrease in another variable.
- Example: If stress levels and quality of sleep have a negative correlation, as stress levels increase, the quality of sleep tends to decrease.
- Interpretation: The variables move in opposite directions. When plotted on a scatterplot, the data points slope downward from left to right.
Key Points
- Correlation Does Not Imply Causation: Just because two variables are correlated does not mean that one causes the other. There could be other underlying factors influencing the relationship.
- Strength of Correlation: The closer the correlation coefficient (r) is to +1 or -1, the stronger the relationship between the variables.
- r ≈ 0.1 to 0.3: Weak correlation.
- r ≈ 0.3 to 0.5: Moderate correlation.
- r ≈ 0.5 to 1: Strong correlation.
Understanding correlations is important in psychology as it helps researchers identify patterns and relationships between different variables, which can lead to further investigation and understanding of underlying mechanisms.