Chapter 2 Section 3

1. Chapter 2 Section 3 Methods of Observation Obj: Compare and contrast various methods of observation, and discuss the use of correlation in analyzing results.

2. The Testing Method Psychologists sometimes use psychological tests to learn about human behavior. There are several types of psychological tests. • Intelligence tests measure general learning ability. • Aptitude tests measure specific abilities and special talents, such as musical ability and mechanical skills. • Still other tests measure vocational interests.

3. Personality tests measure people’s character traits and temperament. For example, personality tests might be used to assess whether people are socially outgoing or aggressive. Also could be used to diagnose psychological problems such as anxiety and depression.

4. The Case-Study Method A case study is an in-depth investigation of an individual or a small group. To learn about the people who are being studied, researchers may observe or speak with them, interview others who know them, and find out more about their backgrounds and personal histories. Psychologists use what they learn in a case study to generalize broader principles that apply to the larger population.

5. Freud developed psychoanalytic theory largely on the basis of case studies. Freud carefully studied the people who sought his help. He interviewed some of them for many years, developing as complete a record of their childhoods as he could. He also looked for the factors that seemed to contribute to their current problems.

6. Problems: • Although case studies sometimes offer great insight, psychologists are cautious about generalizing from case studies. This is particularly true of case studies that cannot be replicated. • People’s recollections are filled with gaps and inaccuracies. • Some people intentionally distort their pasts to impress the researcher. • Sometimes without meaning to, researchers subtly encourage people to answer in certain ways to fulfill the researchers’ expectations.

7. Longitudinal and Cross-Sectional Methods To study how people or other organisms change over time, psychologists often use the longitudinal method. In this method, researchers select a group of participants and then observe those participants over a period of time, often years or even decades. Usually, the observations are conducted at intervals, perhaps once a year.

8. Problems with Longitudinal Studies • Needless to say, they are extremely time-consuming. It may take 5 to 15 years to get results. • These studies tend to be expensive. • There is no guarantee that participants will remain available over the long time period that they are to be studied. To avoid some of these problems, psychologists may use the cross-sectional method.

9. In the cross-sectional method, instead of following a set of individuals over a number of years, researchers select a sample that includes people of different ages. The researchers then compare the behavior of the participants in the different age groups. Problems: • Information is less reliable, because it’s not the same individual being studied, not certain what factors cause differences.

10. The Naturalistic-Observation Method Using the naturalistic observation method, or field study, people observe other people or animals in their natural habitats. In the case of people, field settings include homes, schools, office buildings, etc. Psychologists try not to interfere with the organisms they are observing.

11. The Laboratory-Observation Method When it is more practical for a psychologist to observe behavior in a laboratory rather than in the field, this is called the laboratory observation method. Labs can be quite informal, any place that provides the opportunity for observation or experimentation. Psychologists may sometimes use a lab to control the environment of a study.

12. Analyzing Observations Once psychologists have made their observations, they must analyze and interpret them. One method they use is correlation, which is a measure of how closely one thing is related to another. The stronger the correlation between two things, the more closely those two things are related. Psychologists often look for correlations between various characteristics or traits. Example: What is the relationship between stress and health?

13. Positive and Negative Correlation To determine whether there is a correlation between achievement and occupational success, a researcher might compare need for achievement as measured by a personality test, with the salaries of the test takers. There is a correlation between the need for achievement and salaries, and it is positive correlation. That is, as one goes up, so does the other.

14. In contrast, there is a negative correlation between stress and health. As one goes up, the other goes down. Correlation describes relationships. It does not reveal cause and effect. Just because two things are related does not necessarily mean that one causes the other.