Final answer:
Schwinn's in-depth examination of its most successful retailer for better display ideas is a case study, which is an investigative technique focusing on in-depth understanding of a single subject.
Step-by-step explanation:
When Schwinn is studying its most successful retailer in detail to determine better ideas for displaying bicycles, the company is engaging in a case study. A case study is an in-depth investigation of a single entity, group, event, or situation. It involves collecting detailed information and gaining insights into the subject being examined to identify patterns, understand implications, and draw conclusions that may be applied more broadly.
Case studies are part of qualitative research and are particularly useful for understanding complex issues in real-life contexts. They provide concrete examples and allow researchers to observe and analyze outcomes that can lead to the development of new theories or principles. Considering the information provided, we can conclude that the situation described is a case study, not an experiment, a test market, or causal research.