An individual's learning style is usually determined by a pencil-and-paper test--of which there are now more than 50 available, with titles like the Cognitive StyleIndex and the Learning Style Questionnaire.
There is always debate among investors as to whether style investing using index funds or a style-based asset class fund is an active management strategy or a passive one.
For more information on small-cap index fund investing, including a list of funds and ETFs that cover this style, read All About Index Funds and All About Asset Allocation.