What term describes influential individuals who set the values and beliefs of a reference group?

The term that accurately describes influential individuals who set the values and beliefs of a reference group is "opinion leaders." Opinion leaders are individuals who have a significant impact on the attitudes and behaviors of others due to their knowledge, expertise, or social standing within a particular group. They are often looked to for guidance, making them also a critical element in the dissemination of information and the shaping of public opinion.

Opinion leaders typically have established credibility and trustworthiness, which encourages others in their reference groups to adopt similar beliefs, behaviors, or consumption patterns based on their insights. This effect can be particularly powerful in marketing and social contexts, where the opinions of a few can influence the larger group effectively.

While trendsetters and influencers may also play vital roles in shaping trends and behaviors, their definitions can be more generalized and not necessarily tied to the deep-seated beliefs and values that opinion leaders help cultivate within their respective groups. Advisors may possess expertise but do not always hold the same influential position within a group as opinion leaders do. Thus, "opinion leaders" captures the essence of individuals who actively define the culture and choices of their reference groups.