Psychology can be described as the study of human behavior in relation to nature. The study is mainly carried out so as to get information that will help the subject of the study through research (Zechmeister, Zechmeister & Shaughnessy, 2001, p.3). Several research methods have been in use since the study of human behavior was introduced. Some of these methods include: observational, case study, experimental, correlation and quasi-experimental. Zechmeister, Zechmeister & Shaughnessy (2001), asserts that in observational research, the behavior is watched closely and recorded at the end of the exercise. Case study is also another method of research in which the behavior a single subject i.e. an animal, a group of people or an individual is studied and analyzed so as to get the right information about his/ her behavior. Experimental method of research deals with the illustration of the relationship between an effect and its cause by manipulating or inflicting control on all the other variables apart from the ones under study. Co relational method on the other hand observes the relationship between variables but none of them is manipulated. In quasi-experiment research, the relationship between cause and effects is examined but in naturally organized participants based on age, gender, height etc (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 27).
The method that best fits the research that was done on the eight-year-old girl who was found of banging spoon is the experimental method. This is because it involves the study of cause and effect through the manipulation of certain variables (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 24). For this case, the cause was staying in the dinning hall for a long time without food and its effect was banging of the spoon. Thus the variable that was manipulated was to shorten the time in which the subject stayed idle by giving her food immediately she entered the hall. Some of the limitations that may be encountered in experimental method include; there are some situations in which the variables can not be manipulated and also for better results, the variables must be manipulated one at a time or spilt the research question into smaller bits.
For the second case where the researchers were studying the affiliation behavior of girls and boys in a certain college, the best method is the quasi-experiment. This is because, the study was meant to scrutinize cause and effect based on participants who were automatically organized in nature (Zechmeister, Zechmeister & Shaughnessy, 2001, 27). It is thus naturally that more girls seek for companionship than boys because they feel secure in a group. Some of the limitations that this method is facing include; the subjects of the study are already separated by nature thus making this variable impossible to manipulate.
For the third case where students were randomly grouped into groups of two and asked to work either cooperatively or competitively so as to measure the effectiveness of cooperation and competition, the best method that suits it is co relational. This is simply for the reason that the method does not impose any control or manipulation on the variables. Thus for this case, the individuals were left to work on their own without any restrictions and the outcome was entirely free from any kind of manipulation. Another reason is that it examines the co-relation of variables (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 108). The variables here are cooperation and the outcome or/ and competition and the outcome. Thus the participants who worked collectively had a positive outcome compared to those who worked competitively. Some of the limitations that may accompany this method include; correlational method does not determine the cause of the action.
All the methods that have been selected for the various study descriptions given above use the scientific method in one way or the other. The scientific method of research in psychology is used to gather data, answer questions and/ or solve problems in the case study (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 22). It may not give the precise procedure on how to handle specific situations but it always gives guidelines on how to identify a problem, how to draw the study and to collect data, how to analyze this data and finally how to draw conclusion from the analyzed data. Since all the described methods have identified the specific problem, conducted a study which resulted to the collection and analysis of data and eventually drawing of conclusion, then it is with confidence that they have used the scientific method.
Since research can indirectly or directly cause physical, cultural or psychological harm to the participants, it is the duty of the investigator to ensure that s/he conducts the research in a principled manner. This is because some ethical issues may arise between him/her and the participants when conducting the research. Most ethical issues are applicable to almost all of the discussed methods of research but there are some that are specific in relation to the study cases that are discussed above under some of these methods. For instance, for the case of the eight-year-old girl, consent is very important. Permission should be granted by the parents before the research is conducted (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 43). For the case of the college students, consent and confidentiality are very important. They should be aware of what is happening and should be assured that no third party will access the data or any other information gathered (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 45). And finally in the last case, participants should be advised on what to do before the commencement of the exercise and be protected as well (Zechmeister, Zechmeister & Shaughnessy, 2001, p. 46).