Final answer:
Factors affecting classification include the correlation between characteristics that provide justification for categories and the selection of criteria that serve the classification's purpose, such as grouping by size in biology or analyzing economic changes in supply and demand.
Step-by-step explanation:
Factors affecting direct and indirect classification involve examining how various characteristics correlate and impact the justification and realism of categories. For instance, in biology, if certain organisms are grouped by size and shape consistently correlates with size, then this correlation provides stronger justification for the groupings.
Similarly, in economics, when analyzing economic change, determining whether it impacts demand or supply involves looking at factors such as changes in production costs due to input prices, technology, weather, and government policies. Classification can be applied across different fields, with the underlying principle being the selection of criteria that best serves the intended purpose of the classification, whether it's for understanding biological diversity or market dynamics.