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አማርኛ Every betting statistic is an estimate whose reliability grows with the number of observations behind it. Five matches of BTTS data tell you almost nothing; fifty tell you something; five hundred pin the rate down. The standard error shrinks with the square root of n — quadruple the data to halve the noise.
The practical filter: before acting on any rate ('they hit over 2.5 in 8 of 10'), ask what n is and what the base rate says. Most 'trends' sold to bettors are ten-game samples of a coin that was always near 50%.
Worked example
A 60% over-2.5 rate from 10 games has a standard error of ±15.5% — the true rate is plausibly anywhere from 45% to 75%, spanning 'bet over' and 'bet under'. The same 60% from 200 games (±3.5%) is actually information.