Sloan Digital Sky Survey

Joseph Sirosh and Rimma Nehme show a SQL Server use case, walking us through the Sloan Digital Sky Survey:

Astronomers wanted a tool that would be able to quickly answer questions like: “find asteroid candidates” or “find other objects like this one”, which originally gave the motive to build the SQL-based backend. Indeed, right from the beginning Jim Gray asked Alex Szalay to define 20 typical queries astronomers might want to ask and then together they designed the SkyServer database to answer those queries. The anecdote is that the conversation went as follows:

Jim: What are the 20 questions you want to ask?
Alex: Astronomers want to ask anything! Not just 20 queries.
Jim: Ok, start with 5 queries.
[it took Alex 30 minutes to write them all down]
Jim: Ok, add another 5 queries.
[it took Alex 1 hour to write them all down]
Jim: Ok, now add another 5 queries.
[Alex gave up and went home to think about them]

Alex (said later): In 1.5 hours, Jim taught me a lot of humility!

Alex (said later): It also taught us the importance of long-tail distribution and how to prioritize.

This is my favorite part of the article.

Related Posts

Explaining Confidence Intervals

Mala Mahadevan explains what confidence intervals are: Suppose I look at a sampling of 100 americans who are asked if they approve of the job the supreme court is doing. Let us say for simplicity’s sake that the only two answers possible are yes or no. Out of 100, say 40% say yes. As an […]

Read More

Introduction To Bayesian Statistics

Kennie Nybo Pontoppidan has just completed a course on Bayesian statistics: Last month I finished a four-week course on Bayesian statistics. I have always wondered why people deemed it hard, and why I heard that the computations quickly became complicated. The course wasn’t that hard, and it gave a nice introduction to prior/posterior distributions and […]

Read More


March 2016
« Feb Apr »