Research Methods in Psychology

Is Psychology a Science?

1. Psychology attempts to make its measurements of concepts objective by using operational definitions. 2. Operational definition: a concept is defined in terms of the variables used to measure it (e.g. hunger could be defined as :hours without food") 3. There are limits ot what psychology can study because some variables cannot be manipulated which makes establishing some causal relationships impossible. 4. However, for the questions that are answerable, psychology uses the scientific method as much as any other science.

Case Studies

A description of the behavior or abilities of a single individual. 1. The theories of the Psychoanalysts were based on case studies. Case studies are subject to confirmation bias: people favor information that confirms their beliefs. 2. Case studies are good for generating research ideas, but poor for testing theories.

Naturalistic Observation

A research technique in which the researcher observes and describes behavior. 1. Example of a good naturalistic observation: Jane Goodall and the chimps (they use termite sticks in Africa/spears). 2. Naturalistic observations are good at answering simple questions. 3. Naturalistic observations do not allow sufficient control to determine the relationships between variables.

Correlational Approach

Attempts to determine the relationship between variables without manipulating the variables. 1. The correlational approach is best used when manipulating the variables being studied would be: a. Impossible or very difficult b. Unethical (can't force people to smoke) 2. The correlational approach can be used to determine if two variables are related, but it cannot be used to determine if there is a causal relationship between variables. a. Causation: A causal relationship exists if a change in one variable results in a change in the other. 3. The direction and strength of the relationship between two variables can be measured by the correlations co-efficient (r). a. The correlation co-efficient varies between +1 (meaning a perfect positive relationship) to a -1 (meaning a perfect negative relationship). b. The closer the correlation co-efficient is to 0, the weaker the relationship is. (0.0 - 0.3 = weak, 0.3 - 0.6 = moderate, 0.6 - 1.0 = strong).

Experiments

Studies in which the researcher manipulates the independent variable and which have random assignment. 1. Independent variable: the variable the researcher manipulates in an experiment. 2. Levels of the independent variable: the specific values of the independent variable that a researcher chooses to use in an experiment. 3. Dependent variable: the variable the researcher measures to determine the effects of the independent variable. 4. Random assignment: occurs when every person in the experiment has an equally likely chance of being assigned to each level of the independent variable. 5. In contrast to all other research techniques, experiments, allow researchers to infer a causal relationship between the independent and dependent variables. 6. Becuase random assignment is done in an experiment, statistical tests can be used to determine the exat probability some variable other than the independent variable caused the change in the dependent variable.

Theory Testing

The goal of research in psychology is to develop theories. 1. Scientific theory: an explanation for a phenomenon that can be falsified and that involves entities that cannot be directly observed. 2. A theory is an explanation which means that it describes how some phenomenon happens rather than just stating the relationship between variables. 3. In order to be a scientific theory, the explanation must be falsifiable meaning that there must be some hypothetical facts that would prove the theory false. a. An explanation that cannot be falsified cannot generate any predictions and therefore cannot be tested. 4. A theory must involve entities that cannot be directly observed because otherwise the explanation can be verified by direct observation and a theory is unnecessary.

Theory Testing

Works by using the theory to generate predictions about observable events. 1. The theory is used to generate a prediction about observable events called a hypothesis. 2. If the hypothesis generated by the theory fails to come out, then the theory is falsified. 3. If the hypothesis generated by the theory is true, then it increases out belief in the theory a little bit (doesn't mean theory is 100% true but it can increase our belief in it).