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Jaeheon Yi
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Everyone -- we're all safe at home in Munich.

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The admission letter was mis-typed.
As has been widely reported by now, the Computer Science Department recently sent incorrect admission emails to about 800 applicants to the MS in CS program at CMU.  We had to retract a few hours later, which caused a great deal of understandable distress among the applicants. Here, I would like to explain how this came about as an unfortunate confluence of a single program error, followed by a chain of several human mistakes.

In the 2013-14 cycle, a bug was introduced into the graduate application and review system.  This bug escaped testing, and in retrospect we do not think our testing framework was adequate.  The bug was not exercised at all during the 2013-14 cycle.  It arose when a database field was changed from a number value to a string, and one comparison was not appropriately updated.  Ironically, for a programming language researcher like myself who has dedicated most of his career to developing expressive disciplines of static typing, this should have been flagged as a static type error but the code was written in PHP.

In the 2014-15 cycle, a change in procedure led to this bug corrupting the database by setting the "admit" bit for many applicants when their applications were marked as "complete".

Alert administrators discovered this before PhD admission letters went out in early February.  The bug was fixed, and all affected degree programs except one were manually corrected. The MS in CS program was overlooked.

All program administrators were notified of the problem and were asked to double-check their admit lists.

Some views of the admit list show only the applicants where the "admit" bit was set manually, so the manual check of the admit list missed the remaining spurious "admits" in the MS in CS program.
Just before auto-generating emails, the system displays the number of emails about to go out and asks for confirmation.  This number showed 800+ (instead of 100+) but was overlooked.  About 800 erroneous admit letter went out mid-day Mon, Feb 16.

The issue was discovered relatively quickly when students in the "decline" pile replied to their admission letter.  It took several hours to determine the nature and scope of the problem and identify the students who had received the erroneous letters.  Brief correction emails went out as soon as we had that information.

Dean Andrew Moore and I followed up with further explanation and apologies to all affected students the following day (Tuesday) and continue to reply personally to inquiries since then.

We are currently running an additional layer of formal review before automated admission emails are sent out. We are in the process of re-evaluating our admissions software and processes to determine how to move forward and avoid such disasters in the future.

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New strings means guitar is like new! Makes such a big difference. I like these savarez strings.

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Adjunct Positions, my garage gallery project, was included in LA Weekly's write up of new alternative art spaces in LA.  Lots of great art spaces in this collection.

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Here's a piece of awesome! I present to you: The Couchike! No wait... the Couchcycle... Sofabike... whatever, just look at it ^JH

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Most of you have no idea what Martin Luther King actually did.

On this day in America when we observe Dr. Martin Luther King's birthday, I offer this memorial. It is probably very different from most of what you will read. Here's an excerpt:

At this point, I would like to remind everyone exactly what Martin Luther King did, and it wasn't that he "marched" or gave a great speech.

My father told me with a sort of cold fury, "Dr. King ended the terror of living in the south."

Please let this sink in and and take my word and the word of my late father on this.  If you are a white person who has always lived in the U.S. and never under a brutal dictatorship, you probably don't know what my father was talking about.  

But this is what the great Dr. Martin Luther King accomplished.  Not that he marched, nor that he gave speeches.

He ended the terror of living as a black person, especially in the south.

I'm guessing that most of you, especially those having come fresh from seeing "The Help," may not understand what this was all about.  But living in the south (and in parts of the mid west and in many ghettos of the north) was living under terrorism.  

It wasn't that black people had to use a separate drinking fountain or couldn't sit at lunch counters, or had to sit in the back of the bus.  

Please read it to the end. It is worth it.

Here's the full article:

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From FaceBook:  A Mighty Girl's page:

Many people are familiar with the famous case of Rosalind Franklin, the British scientist who first discovered the helix shape of DNA by using her knowledge of x-ray diffraction techniques to take the first photo of DNA. Without her permission, fellow researcher Maurice Wilkins later showed her photo to James Watson and Francis Crick, who were also trying to determine the structure of DNA. Franklin's photo allowed them to deduce the structure and, shortly thereafter, they published a series of articles about the discovery, only mentioning Franklin's contributions in a footnote. While Watson, Crick and Wilkins received the Nobel Prize in 1962 for their contributions to science, Franklin had passed away due to cancer four years prior and was not eligible for the award.

While Franklin has become increasingly recognized for her immense contributions to molecular biology, even today, students everywhere learn the story of Watson and Crick's discovery but few are taught about the critical contributions of Rosalind Franklin to understanding the nature of DNA. Franklin's story remains one of the most famous and egregious examples of a female scientist being denied credit for her work due to sexism but, as this fascinating infographic illustrates, there are unfortunately many other examples from throughout history.

To learn more, National Geographic ran a profile piece, which included several of the women featured in this graphic, on "six female researchers who did groundbreaking work — and whose names are likely unfamiliar for one reason: because they are women" at  

Now, we can help these women's important contributions to science be known. If you'd like to introduce your children to the stories of remarkable female scientists, we feature many scientist biographies for both children and teens in our "Scientists" section at  

For stories both real-life and fictional of girls and women confronting gender discrimination and prejudice, visit our "Gender Discrimination" section at  

If you want to encourage your own budding scientist, check out our blog post: “Ignite Her Curiosity: Toys for Sparking Your Mighty Girl’s Interest in Science” at  or visit our entire STEM toy collection at  

Thanks to the Women Rock Science Tumblr page for sharing this wonderful image (

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This article is fascinating. For example,
- There is more hourly internet traffic now than annual traffic in 2000.
- 1 pound of coal's worth of energy needed to transmit 1 GB of data over the wireless network.
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