Final answer:
The observer is often considered a major problem in human behavior observation due to potential observer bias; however, clear criteria and multiple observers can mitigate this. Naturalistic observation offers high validity but also poses challenges in control and setup.
Step-by-step explanation:
The notion that the major problem of human behavior observation is the observer is often true due to the presence of observer bias. Observers may unintentionally influence the results of their observations by seeing what they expect to see or by interpreting ambiguous behavior in a way that supports their hypothesis. This can occur because observers are usually part of the research team and might subconsciously align their observations with the research goals. To mitigate observer bias, clear criteria for behavior recording should be established, and multiple observers should be used to assess inter-rater reliability, which is the consistency between different observers' recordings of the same event.
However, in the context of naturalistic observation, the greatest strength lies in the validity and realism of the data collected, as individuals act genuinely within their natural settings, enhancing ecological validity. The data's authenticity contributes significantly to the generalizability of the findings to real-world situations. Yet, significant downsides also exist, such as the potential lack of control over when and how behaviors can be observed, highlighting the difficulties of setting up and maintaining naturalistic observation studies.