S&P 500 (SPX) Opens Up or Down on April 21?

Updated 3d ago

How to read the numbers

Implied / market-implied YES

The probability of YES implied by current traded prices (mid or last). It is what participants are paying for, not a claim about real-world odds.

Model estimate

A rule-based heuristic from the signal engine when a rule sets one, not a black-box forecast. Some signals only describe liquidity or spreads and may show no model estimate.

Edge / gap

The difference between the model estimate and market-implied, in percentage points (model minus market for YES). Filters may use “largest gap.” This is informational only-not trading advice or guaranteed advantage.

Stance (above / below / near estimate)

Compares market-implied to the model estimate when both exist. Labels are not buy or sell recommendations.

Confidence

A simple UI clarity label for signals (not a prediction). It summarizes the signal’s own magnitude/quality metrics into one of: Low, Mid-low, Mid, Mid-high, or High.

Volume

Reported trading activity for the market, for context on size and liquidity.

Change & sparklines

Movement in market-implied YES over the window labeled on the card-often 24h where data allows.

Signals

Rule-based flags from ingested public data. They are not trade recommendations.

More detail in Methodology.

Finance · market-implied 100.0%

PolymarketVolume ~198,715.179← All markets

Recent price

100.0%

This market will resolve to "Up" if the official S&P 500 Index open price for S&P 500 (SPX) on April 21 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day. This market will resolve to "Down" if the official S&P 500 Index open price for S&P 500 (SPX) on April 21 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day. E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day. If the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding. If SPX does not trade at all during the regular session, the market will resolve 50-50. If either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution. If the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price. The resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under "Historical Prices". US: https://www.wsj.com/market-data/stocks EMEA: https://www.wsj.com/market-data/stocks/emea ASIA: https://www.wsj.com/market-data/stocks/asia

Market summary

This market is currently priced at 100.0%, while BinaryStreaks estimates fair value at 98.0%, indicating a possible -2.0 percentage point difference.

Why this is flagged: Δ6h +59.0 pts · Δ24h +59.0 pts (same direction)

What this means

  • This may indicate the market is repricing new information, or reacting to liquidity and order flow.
  • Signals are informational only and not trading advice.
  • BinaryStreaks uses public market data and deterministic, rule-based analysis.

Execution

YES

No live book

NO

No live book