I agree that numbers that narrow tend to point to a statistical burp as much as anything. But the timing of the change in direction does seem to me to counter that argument to some degree.

As an example... did the numbers shift because of no particular ascribable event? Well, then a statistical hiccup seems more likely a reason. Is there an event we can logically hang the change on? Somewhat less so.

Houston's point is well taken; We're going to be dealing with numbers this tight all through this cycle, if the last few cycles are of any indication. Hell, the votes themselves were on a national basis within the statitsical margin of error. At what point do we begin to logically assume that the (small) number shifts we're seeing are genuine, despite also being within the MOE?

Hard thing to judge, this.

With a vertical axis ranging from 39-49 pct, a swing of 3-4 points is in fact dramatic, is it not? In such a tight race, these are significant changes. Thus the figure does not exaggerate.

It gives the misimpression that wat is likely random sampling error is meaningful variation. That's problematic.

Because the vertical axis ranges only from 39 to 49, even a swing of 3-4 percentage points looks dramatic.

With a vertical axis ranging from 39-49 pct, a swing of 3-4 points is in fact dramatic, is it not? In such a tight race, these are significant changes. Thus the figure does not exaggerate.

I also can't help but think there hasn't been enough time to really measure the affect of the Biden pick.

I agree; its a Sunday night poll and I don't think there is a lot of precedent for VP selection bumps anyway.

And there was something else that happened at the end of last week. Obama personally went negative (the house issue) in a way that I had not ever seen him before.

I think the polling reflect a close race. Not sure that it has any reflection on how the Biden pick is going to affect them.

Because the vertical axis ranges only from 39 to 49, even a swing of 3-4 percentage points looks dramatic.

But, James, I suspect and suppose you know as well as I do that if we were talking about McCain, and his pick, and the polling response was this tepid, the phrase "dead cat bounce" would be out in force in the Dinosaur media.

I don't know what things are like now but back when I was in school I didn't know a single J-school student who ever took a math course.