> data(quakes)> head(quakes) lat long depth mag stations1 -20.42 181.62 562 4.8 412 -20.62 181.03 650 4.2 153 -26.00 184.10 42 5.4 434 -17.97 181.66 626...

R news and tutorials contributed by (552) R bloggers

Earlier, I found an interesting post from Bo Allen on pseudo-random vs random numbers, where the author uses a simple bitmap (heat map) to show that the rand function in PHP has a systematic pattern and compares these to truly random numbers obtained from random.org. The post’s results suggest that pseudo-randomness in

Happy Thanksgiving, everyone. Earlier today, I found an interesting post from Bo Allen on pseudo-random vs random numbers, where the author uses a simple bitmap (heat map) to show that the rand function in PHP has a systematic pattern and compares these to truly random numbers obtained from random.org. The post’s results suggest that pseudo-randomness in PHP is

Converting HTML to plain text usually involves stripping out the HTML tags whilst preserving the most basic of formatting. I wrote a function to do this which works as follows (code can be found on github): The above uses an XPath approach to achieve it’s goal. Another approach would be to use a regular expression. These

The Black-Litterman Model was created by Fisher Black and Robert Litterman in 1992 to resolve shortcomings of traditional Markovitz mean-variance asset allocation model. It addresses following two items: Lack of diversification of portfolios on the mean-variance efficient frontier. Instability of portfolios on the mean-variance efficient frontier: small changes in the input assumptions often lead to