What are the sources of strategic positioning according to porter?
VARIETY-BASED POSITIONING -- produce a subset of an industry's products or services. economically feasible only when a firm can best produce products or services using distinct sets of activities
NEEDS-BASED POSITIONING -- serves most or all of the needs of a particular group of consumers. based on segmenting consumers. arises when there are a group of customers with differing needs and when a tailored set of activities can serve those needs best.