E-Wave for the S&P 500 Index

[JLS]

I'm hesitant to accept that.

Whatever the cause (or reasoning) that would trigger a huge number of stock and option trades, which are mostly done by computers now (and not by floor traders).

Look at NCLH, for instance. I would be trading that but haven't touched it for a few days (AKA staying in cash). I use 1-min charts intraday all the time so not much gets by me. I also use Medved Trader for my charting and it's been very reliable. What I see at end of day just doesn't make sense. There is no correlation between its intraday data (including before and after close) and the daily candle, yet they both utilize the same data.