Well, correlation certainly isn't causation, but being a data-nerd, I had to take a look. I grabbed Anne Hathaway's web presence from Google Trends, and Berkshire-Hathaway's performance from Google Finance. After a little massaging, I dumped the numbers in to R, and there is indeed a reliable correlation between Anne's (per-week) web presence and B-H's weekly average close (or closest preceding close).<p>data: hath$AnneTrend and hath$BerkClose
t = 4.6739, df = 373, p-value = 4.135e-06
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.1372140 0.3286587
sample estimates:
cor
0.2352165<p>It's an R^2 of 0.23, which isn't much, but it's not completely spurious; Scarlett Johansson doesn't show the same pattern (there's a weak correlation, but not reliable at p < 0.05).<p>Pearson's product-moment correlation<p>data: hath$ScarlettTrend and hath$BerkClose
t = 1.7687, df = 373, p-value = 0.07775
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.01016440 0.19071018
sample estimates:
cor
0.09120053<p>However, Scarlett's career hasn't mirrored Anne's all that well. What about someone a little closer to Anne, say, her Oscar co-host, James Franco? Note that apart from that, the two haven't really done anything together (<a href="http://imdb.to/g6vwbp" rel="nofollow">http://imdb.to/g6vwbp</a>), although I'd say they've both come to fame recently.<p>data: hath$JamesTrend and hath$BerkClose
t = 4.5991, df = 372, p-value = 5.826e-06
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.1336854 0.3256934
sample estimates:
cor
0.2319475<p>And that might be the clincher. James's little ups and downs shouldn't match Anne's, and yet his recent rise to prominence seems to share the same, slight relationship to B-K's stock value. Thanks for reading!<p>(edit: Ugh, awful formatting! Apologies.)