S&P 500 (SPX) Up or Down on April 28?

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 0.1%

PolymarketVolume ~198,053.227← All markets

Recent price

0.1%

This market will resolve to "Up" if the official S&P 500 Index closing price for S&P 500 (SPX) on Tuesday, April 28, 2026 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 closing price for S&P 500 (SPX) on Tuesday, April 28, 2026 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 specified closing 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 closing price published by S&P 500 Index for that shortened session will still be used for resolution. If either of the relevant days have 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 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 0.1%, while BinaryStreaks estimates fair value at 2.0%, indicating a possible +1.9 percentage point difference.

Why this is flagged: Δ6h -49.5 pts · Δ24h -49.5 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