W1 Lecture 6: Descriptive and Correlation Research Methodologies
Overview of Research Methodologies
- The lecture focuses on two primary categories of psychological research: descriptive research and correlation research.
- These methodologies serve different purposes in the scientific process, particularly regarding how data is gathered and interpreted.
Descriptive Research
- Definition: Descriptive research is a category of scientific inquiry that focuses on observing and measuring behaviors without establishing specific relationships between variables.
- Key Element: Its primary function is to provide an accurate account of what is happening in a given scenario.
- Core Limitation: It cannot answer questions regarding "how" or "why" specific behaviors exhibit themselves. It identifies the presence of a behavior but does not establish the underlying mechanism or causality.
The Satisfaction with Life Scale (SWLS)
- This scale serves as a practical example of descriptive research.
- Procedure:
- Participants answer questions regarding their satisfaction with life.
- The scores for all questions are added together.
- The total sum is divided by 5.
- Scoring Thresholds:
- A score of 7 indicates the highest level of satisfaction ("really nailed it").
- Scores between 4 and 5 are considered "pretty good."
- Application to Descriptive Research: While the scale provides numerical data on happiness levels, it does not explain why a person is happy.
- Future Research Directions:
- Determining a specific definition for "happiness."
- Evaluating if happiness is consistent across different cultures.
- Investigating the link between economic well-being and satisfaction.
- Statistical Note: The United States has one of the highest levels of economic well-being globally, yet it does not rank at the top for life satisfaction or happiness.
1. Surveys
- Format: Administered via interviews or questionnaires.
- Advantages:
- Capability to cover a massive number of subjects.
- Involves large groups of people at a very low financial cost.
- Challenges in Acquiring Valid Data:
- Deception: Some participants may provide false information (lying).
- Inconsistency: Participants may change their minds between different survey sessions.
- Social Desirability Bias: Subjects may provide what they believe is the "socially acceptable" answer rather than their true feelings.
- External Influence: If participants can see the answers of others, they may follow suit (herd mentality).
- Question Design: Data can be skewed by the specific wording of questions or the sequence in which they are presented.
- Forced Binary Choices: Many participants dislike "either/or" choices as they lack the nuance to capture complex beliefs that might apply in some situations but not others.
2. Scientific Observation
- Definition: The act of watching a person or organism perform specific behaviors.
- Key Features:
- Operational Definitions: Observers look for very specific, pre-defined behaviors that have been operationally defined.
- Expertise: Requires observers who are very well-trained; it is not a casual activity.
- Settings:
- Naturalistic Settings: Observations occurring in real-world environments such as a person's home, a school, a public park, a library, or even a forest (e.g., studying gorillas).
- Laboratory Settings: Observations conducted in a controlled environment.
3. Case Studies
- Definition: An in-depth, longitudinal record of a single individual's interaction with a professional.
- Examples: Medical records stored in manila folders that document clinical history (e.g., broken arms, the flu).
- Limitations:
- The sampling size is equal to one (n=1).
- Because of the limited scope, they are primary sources for anecdotal evidence rather than broad generalizations.
- Historical Context: Sigmund Freud is often criticized because much of his research was built upon case studies, personal experience, and observation rather than the formal scientific method.
Correlation Research
- Definition: Research designed to identify and measure the relationship between two specific variables.
- Distinction: Correlation research does not establish cause and effect; causality is the domain of the experimental method.
- The Correlation Coefficient:
- This is a numerical value that represents the strength and direction of the relationship between variables.
- Strength: The closer the number is to 1, the stronger the relationship.
- Comparative Examples: A coefficient of 0.9 indicates a very strong relationship, whereas a coefficient of 0.02 is very weak.
Positive Correlation
- Dynamic: Both variables move in the same direction—either both increase or both decrease.
- Examples:
- Education: Higher levels of education correlate with higher earning power.
- Diet: Increased adherence to a Mediterranean diet correlates with greater longevity.
- The Third Variable Problem (Confound): A relationship may be influenced by an unmeasured third factor. For instance, longevity might not be caused only by the Mediterranean diet but by other factors like regular exercise, not smoking, or limited alcohol consumption.
Negative Correlation
- Dynamic: As one variable increases, the other variable decreases (inverse relationship).
- Examples:
- Poverty: As poverty levels rise, life expectancy tends to decrease.
- Alcohol: As alcohol consumption increases, physical coordination decreases.
- Procrastination: Research on college students shows that as procrastination increases, the quality of work and academic achievement decrease due to rushing through assignments.
Illusory Correlations and Cognitive Biases
- Illusory Correlation: The perception of a relationship between variables when none actually exists.
- Example: Flipping a coin five times and getting "heads" every time may lead one to believe their flipping style correlates with the outcome. However, the probability for the next flip remains exactly 50/50 (50%).
- Apophenia: The tendency in psychology to see meaningful connections between unrelated or random things.
- Apophany: An "aha!" moment where an individual feels a hidden truth has been unveiled, resulting in a false insight.
- Connection to Order: The human tendency to see order in random events is a root cause of conspiracy theories.
- Conspiracy Theory Examples:
- The Da Vinci Code.
- Theories regarding who killed JFK.
- 9/11.
- Pizzagate.
Visualizing Correlation: Scatter Plots
- Correlations are represented graphically using scatter plots, where each dot represents a specific data point from a subject.
- Positive Correlation Plot: The data points trend upward from left to right.
- Negative Correlation Plot: The data points trend downward from left to right.
- No Correlation Plot: The data points are scattered randomly across the graph with no discernible trend line.