Welcome to financial news - whatever you believe about EMH market movement explanations are 100% noise and post-hoc explanations (and I work for the news provider in question).
The people with really high variance about the state of their health are, on average, not very healthy. If people expected 3% growth for the next decade the S&P might hold steady at 1,500, whereas if people expected growth of between -1% and 2% then the S&P might wildly fluctuate but always stay well below 1,500.
Also, some of the ways that the Fed can help the stock market harm the economy.
The point is that whether the market went up or down, and whether the news was good or bad, the pundits can "explain" the market's movements using whatever evidence they have.
I could use a bit more explanation here. I'm seeing that the scoring mechanisms are claiming Good News, which others have pointed out is a sign of high variance. I'm seeing a quote that talks about the economy being less good than it has been in the past. And I'm seeing the conclusion that the markets seem to be having it both ways.
Isn't it more charitable to see it as a statement that the economy has slowed, and yet fluctuations still happen? If the Kevin dude were the one claiming that the market has seen its biggest gains in 3 weeks (how is that even a useful metric?) AND saying that we are doing worse than ever, then I could easily see the failure of conservation of evidence. But it looks more like two sources arguing over a (probably nonexistent) cause to market movements than a witch trial. In THIS case.
From Bloomberg:
U.S. stocks rallied, driving the Standard & Poor’s 500 Index up from the cheapest valuations since 2009, as weaker-than-estimated economic data reinforced optimism the Federal Reserve will act to spur growth.
The S&P 500 rose 3.4 percent to 1,162.35 at 4 p.m. in New York, for the biggest rally since Aug. 11. All 10 industries in the benchmark gauge rose, with gains ranging between 1.8 percent and 4.6 percent. The Dow Jones Industrial Average added 322.11 points, or 3 percent, to 11,176.76.
“There’s plenty of evidence that the economy has slowed,” Kevin Caron, market strategist in Florham Park, New Jersey, at Stifel Nicolaus & Co., said in a telephone interview. His firm has more than $115 billion in client assets. “The speculation would be that it’s possible that the Fed will say something designed to calm markets and provide a bit of encouragement.”
So, bad news about the economy explains the market going both up and down!
(Presumably, good news about the economy can also explain the market going both up and down.)