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).
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
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).
Pearson's product-moment correlation
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
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 (http://imdb.to/g6vwbp), although I'd say they've both come to fame recently.
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
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!
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
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).
Pearson's product-moment correlation
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
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 (http://imdb.to/g6vwbp), although I'd say they've both come to fame recently.
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
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!
(edit: Ugh, awful formatting! Apologies.)