Reading the evidence
Randomness is variation not predictably explained by the information or model being used. It can produce streaks, clusters and convincing patterns even when no durable signal exists.
Make it click
Scatter grains on a table and the eye will find lines and clusters. The shapes are real in the arrangement but need not come from a repeatable arranging rule.
Now put that into markets
Market histories contain many observations and many possible ways to group them. Some striking results will appear through chance alone.
Random does not mean uniform or patternless in a small sample. Dependence and changing distributions complicate simple coin-flip models.
Use baselines, simulations, multiple-testing controls and fresh data to ask how often chance could create something similar.
Calling unexplained variation random can hide a missing mechanism; calling every visible shape a signal ignores selection. Both claims require evidence.
Takeaway
