r than what is) or of not being especially generalizable to others (Papalia & Olds, 1992).
The naturalistic observation method, according to Papalia and Olds (1992), has the advantage of not subjecting people to artificial or unnatural settings that could, of themselves, distort the behavior being observed. On the other hand, this method is also subject to observer bias, Further, it is associated with lack of experimental control and the inability to support the formulation of statements about any causal relationships between the variables studied.
Similarly, while interview data allows a researcher to go beyond observation in getting information about a person's life, attitudes, or opinions, it also has certain disadvantages. For example, interviewees' memories can be inaccurate or they may fabricate or distort their answers so that they are more socially acceptable to the interviewer (Papalia & Olds, 1992).
An example of qualitative research can be found in the now classic research of Jean Piaget (1962) who used case study methods to construct his theory of human development. This theory was essentially constructed from Piaget's knowledge of biology and his case study observations of his own children.
In general, Piaget observed his children's actions, occasionally intervening, and experimentally altering circumstances in an effort to arrive at causes of their behavior. In the excerpt provided below, Piaget observes a newborn crying, notes his surrounding circumstances, records the effects of his own behavior on the newborn and compares the reaction of the infant to human crying and to another sound.
Obs. 1: On the very night after his birth, T was wakened by the babies in the nearby cots and began to cry in chorus with them. At 0:0(3) [age 0, 0 years, 0 months and 3 days], he was drowsy, but not actually asleep, when one of the other babies began to wail; he himself thereupon began to cry. At 0:0(4) and 0:0(6), ...