Computer Science | Grinnell College

At this CS Table we will run and decipher a collection of interesting one line programs. Short programs can be surprising, mind-bending, elegant, infuriatingly clever, or all of the above. We'll follow a relaxed format, where we will look at a new program, run it on a few examples, then try to figure out how it does what it does.

If you have any programs you would like to contribute, please send them to Prof. Curtsinger via email. All programming languages are welcome. We're happy to bend the definition of "one line" in many cases, but do try to stick to programs that are concise.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.

The CSC 322 ("Team Software Development for Community Organizations") students are wrapping up their multi-semester projects for release and will be presenting the near-final projects at 1:00-2:30pm on Friday, December 9, 2016, in Noyce 3819.

At this CS Table we will discuss a recent turn of events in the presidential election: election security experts are calling for recounts in several critical states. Why are they doing this, and why do we need to recount or audit our elections?

Read these three recent articles building up to this recent call:

• Bruce Schneider. Election Security. In Schneier on Security. Posted on 11/15/2016.
• Ron Rivest and Phillip Stark. Still time for an election audit: Column. Posted on 11/18/2016.
• J. Alex Halderman. Want to Know if the Election was Hacked? Look at the Ballots. In medium.com. Posted 11/23/2016.

In addition, to give you more background on the perils of voting and technology, read this paper by researchers at the University of Michigan, Ann Arbor about breaking into Internet voting systems:

• (PDF) Scott Wolchok, Eric Wustrow, Drawn Isabel, J. Alex Halderman. Attacking the Washington, D.C. Internet Voting System. In Financial Crytography and Data Security. Volume 7397, pp 114–128. Springer-Verlag, 2012.

Printed readings are available at Noyce 3827.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.

This CS Table will focus on two computer science education initiatives: CS Unplugged and code.org. These are interesting new approaches to getting computer science education into high school and grade school with some interesting goals. We'll start with a CS Unplugged exercise before the discussion!

There are three short readings suggested for the discussion on November 22:

• About CS Unplugged
• CS Unplugged Principles
• What do kids really need to know about computer science? New roadmap wins widespread support. Lisa Stiffler, GeekWire.
• Printed readings are available at Noyce 3827.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.

Thursday, November 17, 2016
4:15 p.m. in Science 3821
Refreshments at 4:00 p.m. in the Computer Science Commons (Science 3817)

Sooji Son, ’18, Medha Gopalaswamy ’18 and Jianting Chen ’18 will present "ORC²A Proof Assistant."

There is a natural correspondence between mathematical proofs and computer programs. For instance, a recursive function and its correctness relate directly to inductive proofs in mathematics. However, many undergraduate students feel that there is a disconnect between the required mathematics and computer science curricula. There are several proof assistant tools which have been used by the educational community to introduce such concepts to students, but since these tools are not primarily created for educational purposes, students often do not benefit from them to the expected extent.

We have created an educational tool that draws from the benefits of existing provers and assistants and includes a novel proof language that mimics handwritten proofs. By creating a proof assistant targeted towards introductory computer science students with an intuitive user interface and a rich mechanism for providing constructive feedback, we hope to bridge the gap that many students find between mathematical proofs and program correctness.

Reilly Grant ’18 and Zachary Segall ’18 will present "Semi-Automated Program Synthesis."

Program synthesizers have evolved over the past several decades as a method for generating programs from user specifications. One approach to synthesis is using a type theoretic approach and proof search; the Myth synthesis engine uses this approach. One major difficulty with this synthesis model is the exponential blow up of the search space. To circumvent this issue, we present the Scout synthesis engine, designed for semi-automated synthesis: we expect that the user will be able to prune the search space more intelligently than a fully automatic synthesizer. Our study reveals limitations, advantages, and possible expansions of semi-automated program synthesis.

As computation plays a larger role in society, we are beginning to see cases where algorithms encode the biases of the past. While this phenomenon is widespread, there is a particularly interesting case where computer programs make bail recommendations for suspects in criminal cases.

There are two short readings suggested for the discussion on November 15:

• Battling Algorithmic Bias. Keith Kirkbatrick, Communications of the ACM.
• When Algorithms Discriminate. Claire Cain Miller, The New York Times.
• Printed readings are available at Noyce 3827.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.

Thursday, November 10, 2016
4:15 p.m. in Science 3821
Refreshments at 4:00 p.m. in the Computer Science Commons (Science 3817)

Faculty of the Department of Computer Science will present the department's annual discussion of summer opportunities in CS.

Summer is an opportunity to explore new approaches, to develop new skills, and perhaps even to make some money. But what kinds of things can you do? While students tend to focus on a few options (e.g., internships and research with faculty), a wide variety of opportunities are available.

In this session, we will discuss goals you might set for the summer and some opportunities that can help you achieve those goals. Note that we will not be talking about the details of summer research in our department. Instead it's a broad overview of the kinds of opportunities one might pursue. Some companies are already starting to select interns; you can use time now to build your portfolio, and you can use winter break to prepare additional applications. Handouts will be available for those who cannot attend the talk.

On November 8 in CS Table, we will discuss the state of JavaScript, the language running inside your browser. This is a programming language that seemingly ignores virtually all of the wisdom garnered in programming language design over the last half century, and yet it has a huge devoted fan base and enormous impact worldwide. We'll talk about some of the amusing quirks in JavaScript, briefly dive into the world in which JavaScript developers must operate, and speculate about why JavaScript has still been so successful. As always, you do not need any experience with JavaScript to participate in this discussion.

Readings:

• First, we have an imaginary dialogue between a new JavaScript user and an experienced developer. How it feels to learn JavaScript in 2016. Jose Aguinaga.
• Next, we have an article that should have the title "Ten astonishing things you never knew JavaScript would do to your values". Truth, Equality, and JavaScript. Angus Croll.
• And finally, the always-hilarious James Mickens on the horrors of web development. This was a suggested read last year, so you may have seen it already. To Wash It All Away. James Mickens. USENIX ;login: logout.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.

Thursday, November 3, 2016
4:15 p.m. in Science 3821
Refreshments at 4:00 p.m. in the Computer Science Commons (Science 3817)

Xiaoqiu Huang, Professor of Computer Science at Iowa State University, will present "Developing and using bioinformatics tools for analysis of big DNA sequence data."

Recent advances in next-generation sequencing technology provide an opportunity to develop and use bioinformatics tools for analysis of big DNA sequence data in order to further our understanding of living systems at the molecular level. In this talk, Huang will describe his recent work in developing and using bioinformatics tools to further our understanding of how genetic variation is generated in an asexual plant pathogen.

Huang's previous research interests include development of computer algorithms and software for reconstruction of genome sequences and for finding genes and other functional elements in genomes. He is currently interested in understanding evolutionary processes by applying these computer programs to big data sets of genomic DNA sequences. He is the author of a widely used CAP3 assembly program. He and his collaborators have developed a whole-genome assembly program named PCAP. PCAP has been used by Washington University Genome Center in chimpanzee and chicken genome projects.

On Tuesday, November 1, 2016, we'll discuss what echo chambers are, their pros and cons, and how we ought to change our media consumption in light of them. An echo chamber in the context of media studies is a phenomena where the beliefs of a group are reinforced and amplified through repetition entirely within the group. Paradoxically, while the Internet promises to enable free speech and the transmission and sharing of ideas globally, some argue that it has only served to create silos for like-minded people to avoid interaction with dissenting opinion.

Readings: two short articles about echo chambers with respect to Facebook.

• Brian Barrett. Your Facebook Echo Chamber Just Got a Whole Lot Louder. From wired.com. June 26, 2016.
• Eytan Bakshy, Solomon Messing, and Lada Adamic. Exposure to Diverse Information on Facebook. From research.facebook.com. May 7, 2015.

If you are interested in this topic and want to read more, check out these books: Cass Sunstein's Republic.com and Eli Pariser's The Filter Bubble: How the New Personalized Web Is Changing What We Read and How We Think.

Computer science table (CS Table) is a weekly meeting of Grinnell College community members (students, faculty, staff, etc.) interested in discussing topics related to computing and computer science. CS Table meets Tuesdays from 12:00-1:00pm in JRC 224B. Contact the CS faculty for the weekly reading. Students on meal plans, faculty, and staff are expected to cover the cost of their meals. Visitors to the College and students not on meal plans can charge their meals to the department.