Psychology, Day 3

Psychology's Scientific Method

2. Types of Psychological Research

1. Descriptive Research
1. Observation
2. Surveys and interviews
3. Case studies
4. The value of research

2. Correlational Research
1. Correlation is not causation
2.  the value of correlational research
3. Longitudinal designs

3. Experimental Research
1. Independent and dependent variables
2. Experimental and control groups
3. Some cautions about experimental research
1. Experimenter bias
2. Research participant bias and the placebo effect

4. Applications of the Three Types of Research

Descriptive research:  research that determines the basic dimensions of a phenomenon, defining what it is, how often it occurs, and so on

Case Study/History:  an in-depth look at a single individual

Correlational Research:  research that examines the relationships between variables, whose purpose is to examine whether and how two variables change together

Third Variable Problem:  the circumstance where a variable that has not been measured accounts for the relationship between two other variables.  Third variables are also known as confounds

Longitudinal Design:  a special kind of systematic observation, used b correlational researchers, that involves obtaining measures of the variables of interest in multiple waves over time

Experiment:  a carefully regulated procedure in which the researcher manipulates one or more variables that are believed to influence some other variable

Random Assignment:  researchers' assignment of participants to groups by chance ,to reduce the likelihood that an experiment's results will be due to preexisting differences between groups

Independent Variable:  a manipulated experimental factor; the variable that the experimenter changes to see what its effects are

Confederate:  a person who is given a role to play in a study so that the social context can be manipulated

Dependent variable:  the outcome; the factor that can change in an experiment in response to changes in the independent variable

Experimental group:  the participants in an experiment who receive the drug or other treatment under study--that is, those who are exposed to the change that the independent variable represents

Control Group:  the participants in an experiment who are as much like the experimental group as possible and who are treated in every way like the experimental group except for a manipulated factor, the independent variable

External Validity:  the degree to which an experimental design actually reflects the real-world issues it is supposed to address

Internal validity:  the degree to which changes in the dependent variable are due to the manipulation of the independent variable

Experimenter Bias:  occurs when the experimenter's expectations influence the outcome of the research

Demand Characteristics:  any aspects of a study that communicate to the participants how the experimenter wants them to behave

Research Participant Bias:  occurs when the behavior of research participants during the experiment is influenced by how they think they are supposed to behave or their expectations about what is happening to them

Placebo Effect:  occurs when the participants' expectations, rather than the experimental treatment, produce an outcome

Placebo:  in a drug study, a harmless substance that has no physiological effect, given to participants in a control group so that they are treated identically to the experimental group except for the active agent

Double-blind Experiment:  an experimental design in which neither the experimenter nor the participants are aware of which participants are in the experimental group and which are in the control group until the results are calculated

1. Psychology's Scientific Method

1. Observing Some Phenomenon

2. Formulating Hypotheses and Predictions

3. Testing Through Empirical Research

4. Drawing Conclusions

5. Evaluating the Theory

Variable: anything that can change

Theory:  a broad idea or set of closely related ideas that attempts to explain observations and to make predictions about future observations

Hypothesis:  an educated guess that derives logically from a theory; a prediction that can be tested

Operational Definition:  a definition  that provides an objective description of how a variable is going to be measured and observed in a particular study

Meta-analysis:  a method that allows researchers to combine the results of several different studies on a similar topic in order to establish the strengths of an effect

3. Research Samples and Settings
1. The Research Sample
2. The Research Setting
Population:  the entire group about which the investigator wants to draw conclusions
Sample:  the subset of the population chosen by the investigator for study
Random Sample:  a sample that gives every member of the population an equal chance of being selected
Naturalistic Observation:  the observation of behavior in a real-world setting

4. Analyzing and Interpreting Data
1. Descriptive Statistics
1. Measures of central tendency
2. Measures of dispersion
2. Inferential Statistics
Descriptive Statistics:  mathematical procedures that are used to describe and summarize sets of data in a meaningful way
Mean:  a measure of central tendency that is average for the sample
Median:  a measure of the central tendency that is the middle score in a sample
Mode:  a measure of the central tendency that is the most common score in a sample
Range:  a measure of dispersion that is the difference between the highest and lowest scores
Standard Deviation:  a measure of dispersion that tells us how much scores in a sample differ from the mean of the sample
Inferential Statistics:  mathematical methods that are used to indicate whether results for a sample are likely to generalize to a population

5. Conducting Ethical Research
1. Ethics Guidelines
2. The Place of Values in Psychological Research

7. The Scientific Method and Health and Wellness

6. Thinking Critically About Psychological Research
1. Avoid Overgeneralizing Based on Little Information
2. Distinguish Between Groups Results and Individual Needs
3. Look for Answers Beyond a Single Study
4. Void Attributing Causes Where None Have Been Found
5. Consider the Source of Psychological Information