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Valdosta State University |
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Valdosta State University |
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I. Research: methods used to collect objective data
a. All research is (simultaneously): Basic or applied, and crossectional or longitudinal, and descriptive or experimental.
l. Basic-studies designed to learn more about something than is currently known
Applied-studies that both attempt to learn more about something than is currently know while helping to solve a problem in the here-and-now
2. Crossectional-a study designed to provide information on a wide group (data are collected during a short time period). Longitudinal-data collected (a) on the same subjects,(b) over a long period of time. (Used to pinpoint whether something changes (e.g., IQ, etc.) over one's lifetime.)
3. Descriptive-studies that only (a) describe events, and (b) use dependent variables(can only be used to achieve the goal of prediction). Experimental-studies that establish cause-and-effect by manipulating an independent variable to see how it influences a dependent variable (can achieve all three goals of psychology)
a. Dependent variables-measures of subjects' behavior/performance and/ or characteristics (e.g., demographics) subjects bring with them to the study.
b. Independent variables-environmental events that are manipulated/changed by a researcher to determine how they influence/affect the subjects' behavior.
II. Types of Rseach
DESCRIPTIVE
These studies use dependent variables
to objectively establish the existence and/or magnitude of an
event. Three classes/four types: Naturalistic observations (study
organisms in their natural habitat without inference), Assessements
(standardized tests quantify peoples' aptitude and ability; surveys
measure peoples' beliefs and attitudes), case studies (
III. Most research in psychology uses groups (single subjects are used in some descriptive [e.g., Freud and Piaget] and experimental [usually behavioral ones] studies ). Group research (descriptive or experimental) is used to generalize results to other groups. This requires random sampling, which drives a study's external validity. If the study is an experiment, the researcher will also use random assignment, which drives internal validity ("Did the independent variable, or some extraneous one, cause the change in the dependent variable?").
A. Bias-reduces a study's "believability".
l. Subject bias: single-blind control; Hawthorne Effect; sampling problems 2. Experimenter bias: double-blind control
3. Placebo-fake treatment given to some subjects to control for the effects of other subjects (e.g., experimental ones) "getting" something (ind. var.)
B. populations-all the subjects who could potentially participate in a study. Data is not usually collected from populations because of: expense, physical impossibility; and/or unnecessariness if random sampling is employed. Samples-smaller groups who, ideally (through random sampling), accurately reflect the characteristics of the population from which they are drawn.
IV. Attitudes of Science: research should reflect (and researcher should hold) these beliefs: empiricism, determinism, skepticism, parsimony, serendipity, and scientific manipulation.
V. Simple group experiment:
a. Idea
b. Hypothesis (educated guess)
c. identify population, independent variable(s), and dependent variable(s)
d. randomly select sample
e. randomly assign subjects to at least two conditions: control and experimental groups
f. give subjects in experimental group the independent variable (use, if necessary, a placebo) with control group)
g. measure all subjects in all groups on the dependent variable.
h. analyze (usually statistically) data to see if observed differences are real or due to chance
i. conclusions