SUMMARY OF CHAPTER 1
Psychology's official beginning is marked by the establishment, in 1879, of a formal psychology laboratory in Leipzig, Germany, under the direction of Wilhelm Wundt. With this beginning came the first applications of the scientific method to problems of psychology. As an approach to knowledge, the scientific method is characterized by a reliance on empirical procedures, rather than intuition, and by an attempt to control the investigation of those factors believed responsible for a phenomenon. Those factors that are systematically controlled in an attempt to determine their effect on behavior are called independent variables. The measures of behavior used to assess the effect (if any) of the independent variable are called dependent variables.
Scientists seek to report results in an unbiased and objective manner. This goal is enhanced by giving operational meaning to concepts. Scientists also seek to measure phenomena as accurately and precisely as possible. Measurement involves both physical and psychological measurement. Scientists seek both validity and reliability of these measures.
Hypotheses are tentative explanations of events. To be useful to the scientist, however, hypotheses must be testable. Hypotheses that lack adequate definition, that are circular, or that appeal to ideas or forces outside the province of science are not testable. Hypotheses are often derived from theories. More than anything else, scientists are skeptical. A skeptical attitude is not always found among nonscientists, who may rush to accept "new discoveries" and extraordinary claims.
The goals of the scientific method are description, prediction, and understanding. Both quantitative and qualitative research are used to describe behavior. Observation is the principal basis of scientific description. When two measures correlate, we can predict the value of one measure by knowing the value of the other. Understanding is achieved when the causes of a phenomenon are discovered. This requires that evidence be provided for covariation of events, that a time-order relationship exists, and that alternative causes be eliminated. When two potentially effective variables covary such that the independent effect of each variable on behavior cannot be determined, we say that our research is confounded. Confounding must be avoided if we wish to produce a study with internal validity. The external validity of a study involves the extent to which research results can be generalized to different populations, settings, and conditions.
Scientific theory construction and testing provide the bases for a scientific approach to psychology. Theories have the important function of guiding research and organizing empirical knowledge. Finally, many ethical questions are raised by psychological research; it is important that the science of psychology be carried out according to the highest standards of scientific integrity. Getting started doing psychological research requires us to make several important decisions, including those about what topic to investigate, what is the specific question I wish to answer, and is my question a good one? Finally, we must decide exactly how to do the research.
