Friday, October 28, 2011

Banana Trucks, Stock Traders, iPods and More...

Information interchange is an activity shared by biological, chemical, physical, economic and social systems. As science and technology have accelerated in recent decades, we now routinely deal with enormous amounts of data that we try to model accurately in order to understand. When you think about it, these systems have a lot in common. 

For example, my rudimentary understanding of how stock market trading works, leads me to understand that market traders need to get certain complex data right at the beginning of the market day. Within the first few minutes in fact. Any later, and that data is useless to them.  Incomplete or inaccurate and that data is useless to them. This is essentially the same challenge faced by our wireless car which must receive all its varied sensor data properly.

Information theory provides the starting point for addressing these challenges and those of even more complex natural and artificial information interchange systems alluded to above. Claude Shannon's theorems (greatly simplified and hopefully not misrepresented as a result) assumed that data can be encoded as a string of 1s and 0s and transmitted from one point to another. Shannon's ideas enabled us to understand and address data degradation over distance traveled, effects of interference ("noise") and the recognition that when we encode, store and transmit data we can compress it to save space and reduce latency (i.e. speed things up).

An entire communications industry was spawned as a result of information theory. Among other things, we have been able to leverage our detailed understanding of the costs associated with data compression. For example, have you ever compared the sound of a song played on an iPod with a song played from a professionally mastered CD? Which has better quality? The CD of course. On the other hand, you can store far more songs on an iPod than on a CD. This difference has little to do with "old" or "new" storage media technology. If a 1 hour CD can hold approximately 12 songs, whereas your iPod can hold far more than that, it is because, in order to squeeze additional music on the iPod, you lose some digital bits that supply the greater dynamic range heard on the CD.

You probably don't care though, right? You don't expect professional quality music reproduction coming through those little ear buds. Cycling down the road, jogging along the trail, or wherever you are tearing around dangling your iPod, your primary concern is access to reasonably decent portable music. Conversely, you expect a CD playing on a multi-speaker Surround Sound home theatre system to produce pretty darned nice music, right? I certainly do. Personally, I don't know if I could handle hearing Bohemian Rhapsody in its super compressed format on an iPod. But I could definitely rock to the original Hawaii 5-O Theme Song.

How do we know how to produce just the right fidelity for MP3s, CDs, DVDs, etc? Because information theory has led to a highly accurate understanding of the tradeoffs inherent in different types and amounts of data compression as well as a host of other factors that come into play when deciding the optimal way to transmit data point to point. So we know how to model different audio/video systems and choose the compression, transmission and storage methods most appropriate for a given context. The digital data comprising a Dixie Chicks song will be treated much differently if it is to find its way onto a CD vs. an iPod or the movie theatre. Yet each scenario will be optimal and we understand how to make it so.

If only that was all there is to it. The problem is, not all data manipulation is as straightforward. This is where I want to start calling it "information" rather than "data", because much of the "data" we now study has meaning that cannot be divorced from it - hence is "information".

Consider the modeling of a system for optimal routing of commercial trucks. To keep it as simple as possible, let's say all trucks are going from Point A in San Diego, California to Point B in Chicago, Illinois. A truck full of hazardous waste and a truck full of bananas are definitely not the same animal. The optimal routing of those trucks is not the same. The hazardous waste truck must avoid certain roads and population areas, perhaps certain times of day, even if it takes longer to get from San Diego to Chicago. The bananas on the other hand, must arrive as quickly as possible or else rotten mush will show up at the grocery store. A dynamic traffic routing system must understand the semantics of the data, i.e. what is in each truck en route. In this case, semantics also affects temporal issues - timeliness of arrival. The system must be able to adjust on the fly to all the unexpected things that could happen along the way: snow storm, sink hole, holiday parade, incorrect satellite map of the road! Plus, let's complicate matters even more: if our grocery store in downtown Chicago is deluged at the same time by 50 trucks of perishable produce coming from ports on both coasts, there will be Chaos in The Loop (downtown Chicago). And more likely than not, rotten mush on the shelves and in the dumpsters.

Do you see how our wireless car system design has a lot in common with our commercial truck routing system? This is the same class of challenges that exist within a myriad of natural and human-made systems.  Even if you aren't a professional in any of the fields listed in the opening paragraph, you may begin to see the commonalities within complex information interchange systems. To understand these systems we first have to try and model them, taking into consideration all the relevant variables and their interactions: syntactically, semantically, temporally.

Information theory has to be taken to the next level, to incorporate additional factors. Do you want to hear more about all this from an expert? As you wait for the next installment in these posts, consider tuning in October 31st to an interesting talk on the history and philosophy of information

Not to mention, by doing so, you will get a head's up on the people who are working on "Shannon 2.0".

Thursday, October 27, 2011

The Wireless Car Considered

In order to answer the question(s) posed in my previous post, let's go back to the automobile. Your car. Unless you are into antiques, chances are that your current car is a computer on wheels (thinking from a layman's perspective). You probably know this if you ever have taken your car in for what seems like a small repair and get hit with a gigantic bill because "the chip needed to be replaced". Or, you take your car in and they tell you they will "plug it in and run diagnostics". They download some data, study it, and presto, tweak just the right part of your vehicle. You save money.

The heart of modern automobile engines is a CPU in the engine control unit which serves as a data collection hub. Approximately 150lbs of wiring runs through your car between various sensors and the engine control unit. So when something goes wrong, it might be one of the sensors, it might be a wire, or it might be the CPU. Of course, there are many many advantages to having a CPU in your car as compared to the older technology, but this isn't the right place to go into that. What is relevant however, is the fact that all those wires are MESSY. And HEAVY. And ... complex.

Imagine the advantages that could be gained if those wires could be removed and replaced with wireless broadcasting of sensor signals to the CPU.

150lbs less weight: that's about one adult, or a few kids, or many pets, or a lot of gear. Lighter car, better gas mileage.

No wires: less mess in the cars innards (think like a mechanic to fully appreciate that one).

No wires: less complexity and cost in the manufacturing process - consider the domino effect of not having to figure out placement, routing, materials use, secondary waste generation. The car should cost less to build, thus cost less to the consumer. Economies of scale can be gained if the elimination of wires in favor of wireless becomes standard.

Store the data, compress the data, transmit the data. This is where Shannon (my final hint in the last post) comes in. Claude Shannon, whose seminal work approximately 60 years ago founded what we now know of as Information Theory. Theorems about optimal point to point communication of bits. Your cell phone calls rely on application of information theory as do your Skype calls, iPod and CD storage and other applications too numerous to count. I'll come back to that later because with our automobile scenario

There Are Challenges.

For starters, we would need to make sure that my Subaru, sitting at the stoplight next to your Lexus, doesn't tell your Lexus what to do (in theory this might be fun, but I digress). Non negotiable requirement: my car's wireless transmitters need to be picked up only by my car's CPU.

In addition, my car's CPU would have to juggle incoming signals from many sensors. There are N (meaning I have no idea how many) sensors in my car, each of them likely has a different sampling rate, transmission distances vary point to point, noise is inevitable, delay is inevitable, and there are definitely other parameters that I am not thinking of. To function properly, my wireless car's CPU must receive all the encoded data in sufficiently robust form in a timely fashion.

If you are familiar with classic information theory, you know where I am going. If you aren't, then I'll point out: Shannon's seminal work on data storage, compression and transmission didn't anticipate the kind of requirements involved in developing a functional wireless network automobile.

But there is a group of people working on this exact problem and the larger class of problems of which it is a part. And the results they come up with will effect Biology, Chemistry, Economics, Social Sciences, Engineering, and more.

To Be Continued...

 (I won't make you wait a week)

Thursday, October 20, 2011

An Interdisciplinary Puzzle For You To Figure Out

Today I am going to give you something to ponder for a few days - see if you can figure it out. Then, next week I'll tell you all about an exciting project I learned about this week.

What do biological, physical, social, engineering and financial systems have in common?

Toss in Computer Science. Computing is key to solving the puzzle of what this mystery project is.

A concrete example of where it all comes together involves one of the most prevalent objects in the developed and developing world: the automobile.

Think about how many feet of wiring runs through your car. How many feet do you think there are on average, front to back? Have you ever thought about that?

What does the wiring in your car accomplish and what are the critical factors in its proper functioning (don't forget about temporal issues)?

Wiring: kind of Old School technology don't you think?

Let's say you remove the wiring (or most of it) from your car. What advantages might you get from eliminating the wiring?

WHY DO WE CARE? (hint: economic productivity is one answer)

Hopefully some ideas are popping into your head - crazy ideas are fine. Crazy ideas are very good. Innovation comes from so-called crazy ideas and that is rarely a bad thing.

I leave you with a parting final hint: Claude Shannon.

If you come up with the solution before I post about it you gain enormous brownie points and public acknowledgement of having a highly productive brain. All ideas welcome.

Enjoy your mental percolations.

Wednesday, October 12, 2011

Puzzling Phone Algorithm; Virtual Reality Consumer Product Research

Recently I had a conversation with Franz Dill, who maintains one of the most prolific blogs I have run into. The name of his blog is The Eponymous Pickle, and you might want to think about that name. Once you figure out what that title is all about, you'll have a window into what a conversation with Franz is like. Without letting the cat completely out of the bag I'll just say...really interesting and loaded with ideas.

Before we even got into "the real conversation" something interesting happened. We were discussing the fact that I was on Skype from my computer and he was on Skype from a mobile phone. In comparing our reception quality (which was fine) I noted that if he had another call come through that the Skype call would be dropped. The first time it happened to me it was quite puzzling. One moment the person I was talking to was there, the next moment he was gone. poof. No warning for either of us, just - gone. Franz suggested this was probably the result of call prioritization.

Hmm? Now, looking back on it I'm wondering - that seems like an odd arrangement. Who wrote the software that made the decision that a current call should drop if a new one comes in? Did anyone test that out on users? It doesn't follow usual phone protocol. It also doesn't lead to a positive interaction moment, and in the case of a critical negotiation for example, could be quite disruptive. Why do you think they (whoever "they" is) wrote the algorithm that way?

Moving of the interesting things Franz and I discussed was his role in creating the first Innovation Center at Proctor & Gamble. The Center was (and still is) used to creatively experiment with the impact on consumers of various home and store environments. They took over a warehouse in the middle of a cornfield and built a house inside it (yes, you read that right) and later built a store next to the house - inside the warehouse. Apparently one reason to build a house inside a warehouse was so they could make constructive adjustments to the facility (such as punching holes in the wall :)  for the purpose of improved experimentation and monitoring. Presumably, having your own house in a warehouse meant that the house could be recreated and repurposed over and over again as needed.

Franz and his colleagues performed all sorts of experiments with real consumer/users and these experiments eventually moved into the realm of virtual reality. For example, they created wall size displays that people could interact with (you can see a picture of one and read about it in detail in the Eponymous Pickle).

I wonder if the current development team is working on a 3-D virtual store yet. Imagine what it would be like not only to look at and touch the wall display but to reach out and pick up items items off a virtual shelf and put them in a virtual shopping cart. Or perhaps pick up virtual items and put them in a physical shopping cart. The technology to do this exists. I didn't ask Franz about 3-D virtual consumer experimentation and I wish I had.

What do you think the consumers/users reaction to virtual 3-D shopping would be? (That!)

Friday, October 7, 2011

Ada Lovelace Day: Thank You Nell Dale

Today is Ada Lovelace Day, and there was a call put out to write about someone who has made a difference in your life. After thinking it over, I decided that I want to write about someone who through a act of kindness, trust and a willingness to take a risk completely changed the course of my career.

I'm speaking of Nell Dale, who is well known to almost everyone in the ACM SIGCSE community and many people beyond it.

In the 1990s I was working full time as a computer science instructor at a wonderful community college - Chemeketa Community College in Salem, Oregon. I was in charge of all aspects of the transfer program. The position was wonderful, exciting and stimulating, with significant responsibilities - in some ways a dream job.  I was developing all the transfer courses and teaching all of them, I was running around the state of Oregon creating articulation agreements with the Universities, I was doing....many things. I could see the direct results of my work on students' lives. I had an inkling that I was interested in research so I just started doing it by the seat of my pants. I certainly had no formal training in it at that time. It was exciting.

However, as not only the only woman in the department, but the only CS faculty member who had a formal computing background (I'm pretty sure) and the only one interested in research as well as in teaching, it was sometimes a bit lonely.

Along the way I heard about the ACM Special Interest Group on Computer Science Education (SIGCSE) and I joined the listserv and conversations. It was wonderful to have others to exchange ideas with.

Somehow, through that channel Nell, who was on the computer science faculty at The University of Texas at Austin, learned of my existence. One day I received an invitation to be a member of a panel she was putting together for the next SIGCSE conference. I had no idea Nell was so well known and highly regarded or that she was right smack in the center of everything SIGCSE. I had no idea that SIGCSE was a conference loaded with people who I would eventually come to think of as family. All I knew was that I received this invitation from a complete stranger, asking if I'd like to be on a conference panel and I said Yes. The panel was accepted, and the next thing you know I went to San Jose and met Nell Dale in person shortly before we gave our presentation!

I was in the "wow wow wow" stage, and showing my newbieness by trying to get my hands on every free textbook that I could and stuff them into my exploding suitcase. During one of the conference lunches, Nell and I were talking and I said something about my interest in conducting research. Nell said: "You should come to Austin. The University of Texas at Austin has a computer science education research group". I didn't know much about UT and I knew nothing about Austin - or Texas for that matter. Both are now places very dear to my heart. During and after that lunch I thought about Nell's comment. Long story short, a few years later I picked up and went back to school for my doctorate, where Nell indeed was leading a wonderful group of people all interested in computer science education. Participating in that group was a wonderful experience, full of synergy, exciting ideas, passion. I had found a home. One thing led to another and I eventually created an interdisciplinary dissertation and coursework that spanned computer science, psychology, science education and math education. My education and the supportive relationships I formed in those almost-7 years were incredible.

None of this would have happened, the snowball would never have started rolling, if Nell hadn't reached out one day over a listserv to a complete stranger and asked if she wanted to join a panel. I have always remembered those acts of generosity to a newbie and have tried to emulate her actions in my own.

Thanks Nell.