In the past two days, the S&P 500 (SPY) has risen by over 1.4%, while the oil and gas stocks ($XOI) have dropped by over 1.26%. My thought was that this configuration would be bullish for SPY, as it suggests a favorable outlook for companies in the face of falling oil prices.
Since January, 2003 (N = 782), we have had 14 days in which the two-day SPY has been up by over 1% but the oil stocks have been down by .9% or more on a two-day basis. This is an unusual configuration, as daily price changes in SPY and XOI correlate by over .50. Five days later, SPY was up by an average 1.09% (10 up, 4 down). This is much stronger than the average five-day price change for the sample (.22%) and for periods in which SPY has been up by more than 1% over two days (.33%; N = 151).
This is admittedly a small sample, and in the very near term, it has not paid to buy stocks after a two-day runup. Still, the non-oil components of the weighted large cap indexes must be strong to overcome the weakness in the energy issues--strength that appears to carry over to the following several days of trading.