Introduction to personality  (Page 14/21)

A variety of methods have been used to study personality. Much of the early research was based on clinical observations, which were not done according to strict experimental methods. Today, ethical restrictions on the types of research we can conduct with people limit our ability to re-evaluate many of those classic studies. So we are left with a field that is rich in theory, but somewhat poor in the validation of those theories. Of course some personality theorists have approached personality in a more scientific manner, or at least they have tried, but that has limited the questions they have been able to ask. Since a detailed analysis of experimental psychology and research design is beyond the scope of this textbook, we will only cover this topic briefly (though it may come up again within individual chapters).

Case Studies

Many of the best-known personality theorists relied on case studies to develop their theories. Indeed, it was after seeing a number of patients with seemingly impossible neurological complaints that Freud began to seek an explanation of psychological disorders. Basically, the case study approach relies on a detailed analysis of interesting and unique individuals. Because these individuals are unique, the primary criticism of the case study approach is that its results may not generalize to other people. Of greater concern, is the possibility that early theorists chose to report only those cases that seemed to support their theories, or perhaps they only recognized those elements of a patient’s personality that fit their theory? Another problem, as mentioned above, is that two different theorists might view the same cases in very different ways. For example, since Carl Rogers worked initially with children, he found it difficult to accept Freud’s suggestions that even children were motivated primarily by sexual and aggressive urges. Consequently, Rogers sought a more positive view of personality development, which led to the establishment of the humanistic perspective. Thus, the case study approach can lead to very different conclusions depending on one’s own perspective while conducting research. In other words, it can easily be more subjective than objective, and psychologists who focus on our field as a scientific discipline always strive for more objective research.

Correlational Designs

When conducting correlational research psychologists examine the relationships that exist between variables, but they do not control those variables. The measure that is typically used is the correlation coefficient , which can range from –1.0 to 0.0 to +1.0. A value close to zero suggests that there is no relationship between the variables, whereas a value closer to –1.0 or +1.0 suggests a strong relationship, with the direction of the relationship determining whether the value is positive or negative. It is important to remember that the strength of the correlation is determined by how far the correlation coefficient is from zero, not whether it is positive or negative. For example, we would most likely find a positive correlation between the number of hours you study for a test and the number of correct answers you get (i.e., the more you study, the more questions you get right on the test). On the other hand, the exact same data will give us a negative correlation if we compare the number of hours you study to the number of questions you get wrong (i.e., the more you study, they fewer questions you get wrong). So the way in which you ask the question can determine whether you have a positive or negative correlation, but it should not affect the strength of the relationship.