The aim of science is to provide new and useful information in the form of verifiable data obtained under conditions such that other qualified people can make similar observations and obtain the same results. This task calls for orderliness and precision in uncovering relationships and in communicating them to others.
- Experimental Method
An experiment is a test, a procedure used to find out something not presently known. Experiments are usually carried out in order to discover the cause of a phenomenon. The experimental method is a matter of logic, not of location. Even so, most experimentation takes place in special laboratories, chiefly because the control of conditions commonly requires special equipment that is best housed and used in one place. The laboratory is generally located in a university or a research institute of some kind, where it is accessible to scientists who work on a variety of topics.
The distinguishing characteristic of a laboratory is that is a place where the experimenter can carefully control conditions and take measurements in order to discover orderly relationships among variables. A variable is something that can occur with different values. For example, in an experiment seeking to discover the relationship between learning ability and age, both learning ability and age can have different values, learning being either slow or fast and the learner being either young or old. To the extent that learning ability changes systematically with increasing age, we can discover an orderly relationship between them.
The ability to exercise practice control over variables distinguishes the experimental method from other methods of observation. If the experimenter seeks to discover whether learning ability depends on the amount of sleep a person has had, he can control the amount of sleep by arranging to have several groups of subjects spend the night in the laboratory. One group might be allowed to go sleep at 11:00 P.M., another at 1.00 A.M., and the third group might be kept awake until 4:00 A.M. By waking all the subjects at the same time and giving each the same learning task, the experimenter can determine whether the subjects with more sleep master the task more quickly than those with less sleep.
In this study, the different amounts of sleep are the antecedent conditions, the learning performances are the results of these conditions. We call the antecedent condition the independent variable because it is independent of what the subject does. The variable affected by changes in the antecedent conditions is called the dependent variable; in psychological research the dependent variable is usually some measure of the subject’s behavior. The phrase “is a function of” is used to express the dependency of one variable on another. Thus, for the experiment above, we could say the subject’s ability to master a task is a function of the amount of sleep he has had.
iii. Degree of Control
The degree of control possible in the laboratory makes a laboratory experiment the preferred scientific method when it can be used appropriately. Precision instruments are usually necessary in order to control stimuli and to obtain exact data. The experimenter may need to produce colours of known wavelengths in vision studies, or sounds of known frequency in audition studies. It may be necessary to expose a pattern in an aperture of a viewing screen for a fraction of a second. With precision instruments, time can be measured in thousandths of a second, and physiological activity can be studied by means of very slight electrical currents amplified from the brain. Thus, the psychological laboratory has audiometers, photometers, oscilloscopes, electronic timers, electroencephalographs, and computers.
iv. Value of an Experiment
The value of an experiment is not determined, however, by the amount of apparatus used. If the logic of experimentation requires precision apparatus, then such apparatus should be used; if does not, good experimentation can be carried out with pencil-and-paper procedures.
2. Observational Method
In the observation method, the investigator will collect data through personal observations. In this method the investigator will observe the behavior of the respondents in disguise. Take the case of customers transacting with a bank. Here, the behavior of the customers like, patience while waiting, way of moving with the bank employees, helping fellow customers in filling different forms, informing the bankers if there is any excess credit in their pass books, returning excess currency to the cashier if given by him, opinion of the customers about the bank through their casual discussions, time spent in reading circulars in notice board, etc. will be observed by the investigator. Continuous monitoring of stock exchange index and share prices movements through newspaper and magazines is an example of observational method which will help investment companies and individuals effective management of portfolios.
3. Survey Method (Field Studies)
Those problems which are difficult to study by direct observation may be studied through the use of questionnaires or interviews. Surveys are usually appropriate in case of social and behavioural sciences. Surveys are concerned with describing, recording, analyzing and interpreting conditions that either exist or existed. The researcher does not manipulate the variable or arrange for events to happen. Survey are only concerned with conditions or relationships that exist, opinions that are held, processes that are going on, effects that are evidence or trends that are developing. They primarily concerned with the present but at times do consider past events and influences as they relate to current conditions. Thus, in surveys, variables that exist or have already occurred are selected and observed.
Surveys have also been used to obtain information on political opinions, consumer preferences, health care needs, and many other topics. An adequate survey requires a carefully pre tested questionnaire, a group of interviewers trained in its use, a sample carefully selected to ensure that the respondents are representative of the population to be studied, and appropriate methods of data analysis and reporting so that the results are properly interpreted.
4. Case Studies
The case study method involves careful and complete observation of a social unit a person, a family, an institution, a cultural group or even the entire community. The case study is essentially an intensive investigation of the particular unit under consideration. The objective of the case study method is to locate the factors that account for the behavior patterns of the given unit as an integrated totality.
5. Test Method
This method is used to measure all kinds of abilities, interests, attitudes, and accomplishments. Tests enable the psychologist to obtain large quantities of data from people with minimum disturbance of their living routines and without elaborate laboratory equipment. A test essentially presents a uniform situation to a group of people who vary in aspects relevant to the situation (such as intelligence, manual dexterity, anxiety, and perceptual skills). An analysis of the results then relates variations in test scores to variations among people. Test construction and use are, however, no simple matters. They involve many steps in item preparation, scaling, and establishing norms.