Nanex Research
Nanex ~ Stock Price Correlation
The chart below plots 1,454,432 trades for all 7,800 NMS stocks priced between $0.0001
and
$140 during a 17 minute period during the FOMC announcement on December 12, 2012. It
uses a 1 second resolution interval - which means each pixel is 1 second of time. The
SEC used 1 minute "samples" in their flash crash report. It's hard to see any patterns
at even 1 second resolution. Trades for the symbol SPY are the string of dots
near the top at $144.
One second resolution chart of trades color coded by exchange. Chart shows 17 minutes
of time.
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The charts below illustrate how often hundreds of stocks are executed at the same time (within milliseconds). These are likely the result of stat-arb algos: based on correlation with ETFs or other instruments.
Look for vertical lines, which occur when many stocks,
all at different price levels, execute in the same time interval. Click Start/Stop to run a slide show of all 17 images, or Prev/Next to step through them one
at a time.
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