Best Dataset Ever

This is an end-of-semester thing that we’ve been looking forward to.  Back in mid-October, I thought it would be fun to record our sleep and wakeup times.  We started on October 14th, and here are the results from calculating hours slept.  I think we have a lot less than the average number of all-nighters for college students.

You can download the dataset (csv format) here.

Note: the hours slept are calculated for the night before, e.g. Sunday values correspond to hours slept Saturday night through Sunday morning.

Summary (hours):

As you can see, Danny, Duncan, and Tom have left-skewed distributions (the mean is less than the median) whereas I’m right-skewed.  I have the highest mean sleep time and the lowest standard deviation.  Tom has the highest standard deviation, and Duncan has the lowest mean sleep time.  Graph:

Days of the week:

We were also curious about our sleep patterns during the week.  Tom was usually very well rested on Tuesdays.  Graph:

Correlation Matrix:

Unsurprisingly, I am not very correlated with the others.  Duncan and Tom have the highest correlation.

My hours:

My variance increased over the semester.  Graph:

Danny:

Thanksgiving break meant a lot of sleep for Danny.  Graph:

Duncan:

I bet you can tell when Duncan had an astronomy lab write-up.  Graph:

Tom:

The wild roller coaster ride that is Tom’s sleep schedule.  Graph:

All of us:

Confirmation

It turns out that Charles was right. Here is an e-mail that was sent to someone in the Harvard Society of Physics Students:

———- Forwarded message ———-
From: Randall Munroe
Date: Tue, Dec 15, 2009 at 12:25 PM
Subject: Re: the harvard physicists are on to you: (was: Fwd:
[sps-open] xkcd and galactic rotation curves)
To: Jacob Rus

It’s a coincidence, but I swear I’ve seen that graph before. I
remember wishing I could see the error bars and data points.

Best,
Randall

CS50 Projects!

Hey everyone, as you may or may not have known, the CS50 fair was this past Tuesday, and three of us participated (Danny’s too good for CS50, although we did try to get him to TF the course).

Note: The cloud is being reset on January 1, 2010, so the links will no longer work  soon.

Charles’ Project:

An automated trading system analyzer written in Python3 (eventually going to be moved to its own domain).     http://cloud.cs50.net/~li15/fp/

Duncan’s Project:

A course selection tool that randomly selects appropriate Core classes.  http://cloud.cs50.net/~dwatts/final

Tom’s Project:

An interactive speech recognition program named “Hal Py-Thousand.”  Source Code:  http://www.blandfill.com/tomstuff/CS50.rar

Danny:

Look at the post below for one of Danny’s many projects.  http://www.blandfill.com/2009/12/13/gchat/

GChat

Someone in the room mentioned that we should create a GChat bot that would let us all talk together without the hassle of creating a chat room each time. Having used xmpppy before, I went and did it.

The result:

(Charles changed my GNOME theme to pink some weeks ago.)

Tom then wanted me to write a post about how I did it, so here it is. Without going into a description of the library itself, it works as follows: when it gets a message from one of us, it prepends the appropriate initial and sends the message to the rest of us.

I guess I can go a little more into the details of the library (especially because the documentation is pretty annoying). (There still isn’t really that much to say.) You run some commands in the library to create a connection and log in, then register a function with the connection object to handle incoming messages. I suppose I can add more description if anyone wants. Code.

So that I can get all the tags:
http://acme.com/jef/singing_science/
http://www.youtube.com/watch?v=OM0ib4GxLPw

xkcd is so much better than I could have imagined

After doing a lab about galactic rotation curves, the following xkcd comic has gained more meaning for me;

Escalators

If this isn’t explicit enough for you, please compare it to the following;

Shock and awe.

Update (more…)