fnichol

Why?

There is a long standing issue in Ruby where the net/http library by default does not check the validity of an SSL certificate during a TLS handshake. Rather than deal with the underlying problem (a missing certificate authority, a self-signed certificate, etc.) one tends to see bad hacks everywhere. This can lead to problems down the road.

From what I can see the OpenSSL library that Rails Installer delivers has no certificate authorities defined. So, let's go fetch some from the curl website. And since this is for ruby, why don't we download and install the file with a ruby script?

Installation

The Ruby Way! (Fun)

mbostock

license: gpl-3.0
border: no
height: 960
redirect: https://observablehq.com/@d3/scatterplot-matrix

mbostock

license: gpl-3.0
border: no
height: 960
redirect: https://observablehq.com/@d3/brushable-scatterplot-matrix

mbostock

license: gpl-3.0

hadley

.Rproj.user
.Rhistory
.RData
*.Rproj
*.html

hadley

If you were to give recommendations to your "little brother/sister" on things that they need to do to become a data scientist, what would those things be?

I think the "Data Science Venn Diagram" (http://drewconway.com/zia/2013/3/26/the-data-science-venn-diagram) is a great place to start. You need three things to be a good data scientist:

• Statistical knowledge
• Programming/hacking skills
• Domain expertise

Statistical knowledge

johnmyleswhite

• Correlation is not causation (???)
• No causation without manipulation. (Holland)
• All models are wrong, some are useful. (Box)
• Statistics is the science of uncertainty. (arguably Tukey)
• Statistics is the science of learning from experience, especially experience that arrives a little bit at a time. (Efron)

khakieconomics

# Some fake data

library(dplyr); library(rstan)

# Write out the data generation with known parameters

# Set the number of individuals
n_ind <- 50

teknikqa

// On the Last.FM website go to the page which lists the tracks that you have loved.
// Open Chrome DevTools (or Firefox or any modern browser that has a built in Javacript Console)
// and run the following command.
// This basically clicks on all the delete buttons on the page and reloads the page.
jQuery('.love-button--loved').each(function(_, b) {
  b.click();
});
location.reload();

mike-lawrence

functions{
	// GP: computes noiseless Gaussian Process
	vector GP(real volatility, real amplitude, vector normal01, int n_x, real[] x ) {
		matrix[n_x,n_x] cov_mat ;
		real amplitude_sq_plus_jitter ;
		amplitude_sq_plus_jitter = amplitude^2 + 1e-6 ;
		cov_mat = cov_exp_quad(x, amplitude, 1/volatility) ;
		for(i in 1:n_x){
			cov_mat[i,i] = amplitude_sq_plus_jitter ;
		}