A worked distinction
A coin quoted at 100 USDT on one market and 100 USD on another has no measured USD spread unless the value and conversion cost of USDT are also known. A quote-asset deviation can create or erase the apparent difference.
What to verify in your own analysis
Keep quote currencies visible, verify redemption access separately and include conversion fees if an actual conversion is part of the strategy.
Write down the market or protocol identifier, units, observation window and data source before comparing outputs. Keep unavailable values distinct from zero. Capture a baseline and change one assumption at a time so the resulting difference can be explained.
Use the linked working tools
Open the related tools below to inspect actual public observations or calculate a local scenario. The numerical example above is illustrative, not a current quote. Export the result together with its assumptions if you need a reproducible research record.
The review checklist records what you checked in this tab. Completion measures your own notes, not whether an investment is safe, suitable or profitable.