How do psychologists measure behavior and experience?
Whatever method pyschologists use they find it necessary to make statements about amounts or quantities and thus can be measured. Measurement relates to the identification of both the qualitative and quantitative. A set of values that goes up or down is called a scale. There are nominal scales, ordinal scales, and interval scales. Quantitative data are called scores which are handled in statistical ways.
1. Experimental design is used to describe the procedures used in planning an experiment. The simplest experimental designs are those in which the researcher observes one variable called "independent" variable and finds out its effects on another variable called "dependent" variable. Other experimental designs call for a group called "experimental group" and another group called "control group". In the first group the condition or variable is present. In the second group, this condition or variable is absent. Example: The experimental group of grade six pupils uses computer assisted learning (CAL) modules in Mathematics while the control group does not. At the end of the year both groups are given a standardized mathematics test to find out which group scored higher in mathematics. In this experiment the independent variable is the CAL and the dependent variable is the pupil's score on the test.
2. Statistical measures
a) Normal distribution curve. This is the standard symmetrical bell-shaped frequency distribution used in making statistical inferences.
b) Measures of central tendency. This is a frequency distribution namely, mean, median, mode, of a distribution of scores.
c) Correlation. This is the numerical index used to show the degree of relationships between two sets of paired measurements. Example: "The relationship between the first year high school students' mental ability and their work attitudes." The findings of the study will show whether the relationship is positive or negative.
d) Statistical inference. This is a statement about a population based on a statistical measures derived from samples. A researcher who says that the difference between the experimental and control group is "statistically significant" means that the observed difference is likely to occur again if the experiment is repeated based on the statistical tests that have been applied to the data gathered.
How are computers used in psychology?
Computers are being used in psychology to provide fast means of analyzing data laboratory control, and even theory construction. Computers are justify famous for their speed and for their vast storage capacity. The programmer can write once and then simply "call" whenever it is needed that much time and effort can be saved. Computers have proved useful in the laboratory by providing greater standardization of procedures and more accurate recording of data.
