Friday, September 09, 2005

Post-Katrina Overall Job Approval for President Bush

Post-Katrina Overall Job Approval for President Bush Posted by Picasa

An earlier post (here) presented data on public approval of President Bush's handling of the Hurricane Katrina situation. There the data show a clear decline in the President's rating over the past 9 days.

But what about his overall rating as president? The polling is only beginning to trickle in on that question, but here are the early returns. There have only been five post-Katrina readings of overall job approval. The first two, by CBS and Fox, completed interviews on 9/31, the first day after Katrina hit, so provide an important measure of initial reactions. CBS found a 41% approval rate, while Fox's was 45%. The three polls since then, by Pew, Zogby and CBS all finished interviewing on 9/7. Their approval numbers are 40, 40 and 42 respectively.

Both Zogby and Pew show significant drops, from 45% and 44% approval in their previous polls. However, those previous polls were taken way back in July. August was not a good month for the President's polls, so attributing all the decline to Katrina is a significant overstatement.

The CBS polls, taken 8/29-31 and 9/6-7, provide the best "before (well, early at least) and after" comparison. In this case, Bush's approval actually rises from 41 to 42%.

We can push the results a little more.

In the figure, I plot the 89 national polls taken since President Bush's second inauguration. It is clear that during this time, approval has fallen in a basically linear fashion, dropping at the same rate from January through August. There is also considerable variation across polls, much (though far from all!) due to differences between polling companies. So to estimate the effect of Katrina on approval, we should account both for the linear trend, and for "house" effects between different companies.

When we do that, the result is an estimate of -.52 for the post-Katrina effect, a decline of about a half a percentage point in approval. With the few polls and modest effect, this is far from statistically significant (p=.61).

The moral is that, if there is a decline in the president's overal job approval, it appears modest, though the data we have so far will support no firm conclusion of any change at all. No doubt there will be a flood of new data in the next week, providing more leverage for this estimate.