Does betting on hot numbers work?

How Hot number (Andrucci-style) is played

1. Sit out the first 37 spins and count every result.
2. From then on, bet one unit straight-up on the number with the most hits so far (ties go to the lowest number).
3. Keep counting; the pick changes when another number pulls ahead.

What 20,000 sessions show

Sessions that finished ahead were up $252.55 on average; sessions that finished behind were down $638.61. 9.6% of sessions ended because the next stake no longer fit the bankroll or the table limit. 24.2% reached the 500-spin cap without hitting the target or busting.

On a physically biased wheel, tracking frequency is how advantage players found an edge, but it takes thousands of spins to tell bias from noise. Over a few dozen spins the hottest number is just the luckiest one, and on an unbiased RNG every number still hits 1 time in 37.

The median session lasted 208 spins. The median longest losing run was 64 spins in a row (the worst of 20,000 was 239), and one session in ten put at least $5 on the table in a single spin.

European versus American wheel

The same 20,000 seeds, replayed on a double-zero wheel. The second zero roughly doubles the edge to $5.26 per $100 wagered. Measured return goes from −$2.73 to −$5.55 per $100, and the mean session from −$30 to −$64.

The code that produced these numbers

This Lua is the strategy as Engineer mode runs it, inside the same sandbox and kernel. A test in the repository replays it against the bulk generator on fixed seeds and fails the build if the two ever disagree by a single dollar.

-- Hot number (Andrucci-style): watch 37 spins, then bet straight-up on whichever number has hit most.
-- Session rules shared by every 0xroulette.com/systems page:
-- $5 unit, $500 table max, walk away at +$200, and stop the moment
-- the next stake can't be covered by the bankroll or the table limit.
local UNIT, TABLE_MAX, TARGET = 5, 500, 200

local seen, hits

local function reset() seen, hits = 0, {} end

local function place(ctx)
  if seen < 37 then return {} end
  local keys = { "0" }
  if ctx.variant == "american" then keys[2] = "00" end
  for n = 1, 36 do keys[#keys + 1] = tostring(n) end
  local best, most = nil, 0
  for _, k in ipairs(keys) do
    local count = hits[k] or 0
    if count > most then best, most = k, count end
  end
  local pocket = best == "00" and "00" or tonumber(best)
  return { { type = "straight", pockets = { pocket }, amount = UNIT } }
end

local function settle(result)
  seen = seen + 1
  hits[result.pocket] = (hits[result.pocket] or 0) + 1
end

-- Shared wrapper: enforces the session rules around place/settle.
strategy = {}
local start, stopped

function strategy.setup(ctx)
  start, stopped = ctx.bankroll, false
  reset()
end

function strategy.bet(ctx)
  if stopped or ctx.bankroll >= start + TARGET then
    stopped = true
    return {}
  end
  local bets, stake = place(ctx), 0
  for _, b in ipairs(bets) do
    if b.amount > TABLE_MAX then stopped = true end
    stake = stake + b.amount
  end
  if stake > ctx.bankroll then stopped = true end
  if stopped then return {} end
  return bets
end

function strategy.on_spin(ctx, result)
  if not stopped then settle(result) end
end

Session rules

Limitations

One bankroll, one unit size, one table limit, and one walk-away target. A bigger bankroll or a higher limit moves where a progression breaks; it does not change the return per dollar wagered. Spins are fair and independent, as on a correctly functioning wheel or a certified RNG. Physical wheel bias is a separate question, covered on Physics.

Related

• Does betting on one number every spin work?
• Does betting against a streak work in roulette?
• Does flat betting work at roulette?
• Study: How many spins bias detection needs
• All 20 systems, compared on the same seeds