The two major types of informal personality assessment techniques are observation and _____________.

The correct choice highlights interviewing as a major type of informal personality assessment technique, alongside observation.

Interviewing involves direct interaction with the individual, allowing the assessor to gauge personality traits based on responses to questions, interpersonal dynamics, and non-verbal cues. It provides a rich context for gathering qualitative data about an individual’s thoughts, feelings, and behaviors, which can be invaluable in understanding their personality. Through structured or unstructured conversations, the interviewer can explore deeper insights and nuances that might not be captured in more standardized formats.

In contrast, self-reporting, testing, and surveying, while valuable in their own right, do not fall under the informal category to the same extent as interviewing. Self-reporting relies on individuals to provide their assessments, testing typically involves standardized measures which may not allow for the same level of depth, and surveying often consists of fixed questions that limit the spontaneity and richness of the information collected. Thus, interviewing effectively complements observation in the realm of informal personality assessments.