Monday, March 22, 2010

Visualization of Today

787 billion dollars to track. Graphs to make. If anyone can do it, Edward Tufte can: he's the data visualization superhero. Read about him taking on the ARRA stimulus package.

Sunday, March 21, 2010

Archaeology at CSULB

Proceedings are on-going for the admission of archaeology graduate students at CSULB for the fall 2010. Stay tuned.

Graphical perception – learn the fundamentals first | FlowingData

Came across this discussion of Cleveland and McGill's work on Flowing Data regarding visualization of data. Things to keep in mind.

When it comes to visualization, especially on the Web, you have to be open-minded, and you should be willing to try new things. There’s no advancing otherwise. However, before you dive into the advanced stuff - like just about everything in your life - you have to learn the fundamentals before you know when you can break the rules.

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[From Graphical perception – learn the fundamentals first | FlowingData]

Saturday, March 20, 2010

What you do need to know before you enter a graduate program in archaeology.

Previously, I argued that traditional field skills are not anything to worry about before entering a graduate school: you can always learn how to dig a hole. Now, you might ask, what skills should I have? Here's the list, based on what I've seen graduate students struggle with during their first years. Having these skills under control will greatly ease your first years and give you time to focus on learning actual archaeology rather than basic mechanics. You might also check out my previous post on my advice for graduate students.
(1) Be able to write. The better you are at writing, the easier your graduate school experience will be, especially in the first few years. In all of your classes you will be asked to write: essays, papers, laboratory write ups, analyses, reviews, etc. Writing is a key part of graduate school. In fact, its basically the product of archaeology. At our core, we are writers who happen to rummage around in dirt, speak conceptually about rocks and other kinds of inanimate things. The better you are at writing, the better an archaeologist you will be. Before you start graduate school, do some writing. Start a blog and keep it current. Turn a paper you wrote as an undergraduate into something for publication - whether that is a newsletter, local publication, regional venue or greater. Take a class in writing at your local community college. Read Strunk and White's Elements of Style. Then read it again. Then read On Writing Well, by William Zinsser. Then practice some more. Make your writing logically sound. Clear. Sharp. Readable.
(2) Learn how to use Microsoft Excel or any equivalent spreadsheet program (whether that be OpenOffice, Gnumeric, Numbers or some other variant). Given that contemporary students are often touted as being terrifically "computer savvy" with all of that YouFace, FaceTube and Twitface stuff, I am incredibly appalled that many entering archaeology students have never used a spreadsheet. I've seen students, for example, enter numbers into a spreadsheet as instructed and then do calculations on a calculator (e.g., summing the values) and then entering the results back into the spreadsheet. Really. Given that much of what we do in archaeology in addition to writing is counting things, have advanced knowledge of Excel will go along way to making your assignments be about the problems posed and not the mechanics of dealing with numbers. Trust me on this one. Learn how to use a spreadsheet, create headers, use autofilter, use functions, create formulas, create graphs, do basic statistics, etc. Equally important: learn how to edit the graphs and tables produced by Excel to make them acceptable. Don't rely on the defaults. Learn to identify "chartjunk" and maximize the information to ink ratios for your graphics. tufte_wallpaper.2vf33bt6eq0wc0scws0kg04kc.bxj7bs82axw0g448owg4gc8so.th.png
(3) Know the basics of statistics. If you count, describe or measure things, you need to understand statistics simply because all of the actions are meaningful only if one understands the contribution of error. Don't hide behind some claim of "phobia" about numbers: if this is really the case, choose another career. Really. If you really are unable to understand the concept of a standard deviation, do society a favor and pick a more suitable career like crematorium manager or whatever. And while you will learn more about statistics in graduate school, if you don't know anything about the basics you will be wasting everyone else's time as you get up to speed. Take an extension class. Read a book on statistics and do the exercises. Practice. Count things, calculate error. Just learn statistics.
(4) Learn some kind of programming language. Some might argue with me about the fundamental nature of this skill, but I definitely believe that every archaeologist should learn at least on kind of programming language: Perl, Basic, Visual Basic, Python, C, C++, C#, shell scripting, Java, Javascript. It really does not matter which language one chooses, but the skills acquired through learning how to take a problem and break it down into simple steps that can be coded will provide a generous payoff for anyone tackling the routine problems facing archaeology students (and professionals alike). Programming is more of a logic problem than anything else and learning how to conceive of problems that can be tackled via a program is a good demonstration that you can figure out how to solve problems in general. And having the skills to program means you are not going to waste your life doing tedious things that you (a) not do well and (b) you shouldn't be doing by hand in the first place. For example, given a large number of files (say 10,000) rename them according to some scheme. If your only solution is to do this take one by one and by hand, you are in trouble. Take a class. Read a book. Do online exercises. Learn some kind of programming. And do it before you are in graduate school.
(5) Learn something about GIS. In graduate school, you will definitely have opportunities to learn something about spatial systems. However, you should gain a background in the basics of geographic systems before you start graduate school. GIS is really just a different kind of computer application - like Word or Excel - that allows you to manipulate concepts in space. No archaeologist worth her/his salt should lack an understanding of GIS. And that means you. The more you know about GIS - like using Word or Excel, the easier it will be to focus on archaeological analyses that deal with space rather than the mechanics of the various program that you are going to use to study space. Learn ESRI's ArcGIS or the open source Quantum GIS or one of many other geographic information systems.
Well, that is a start that should keep you busy for the summer prior to starting a graduate program in archaeology. As I recall other critical skills, I'll update this list. If you have any ideas, please let me know.

Thursday, March 18, 2010

What you don't need to know before you enter a graduate program in archaeology.

When I talk to students about their preparation for graduate school in archaeology, I've noticed that most worry one set of skills that are largely irrelevant for actual success in either a Masters or PhD program: those associated with a "field school." Yes, participating in the long-standing tradition of an unpaid apprenticeship in the field is still considered a "rite of passage" for archaeologists. However, what one learns in such an experience provides only marginal return when it comes to actual success in graduate school or even as a professional. All one can really expect to gain from a field school is knowledge that:

(1) You like (or do not) other archaeologists. Many field settings are remote and force individuals to cooperate and share daily living in a way that leads to somewhat intense experiences. Of course, such an experience could be accomplished doing just about anything (camping, ice slogging, sailing a dingy across the Pacific with 12 of your closest friends, etc.). What makes archaeological field school unique is that it forces you to hang out with other archaeologists. Since those who choose this sort of focus for their lives are an odd breed, it doesn't hurt to find out if you can stand 7x24 discussions with others who share the same bent view of the world as you do.

(2) An appreciation for the fact that archaeological field work is tedious, mind-numbing and occasionally just boring. It just is. Yes, one will have a lot of fun futzing around in the dirt but most of the "fun" comes camaraderie or reflections after the fact (usually over cold beverages in the light of the moon). But the work itself - well, for the most part, trained monkeys can do it. If you can see through the drudgery and still like archaeology, you might have a chance becoming an archaeologist.

(3) Some archaic knowledge about rote and tradition and little else. Most field schools tend to focus on simply repetitive activities that have long stood for archaeology -- "digging." Digging holes in the ground to retrieve artifacts is a time-honored tradition. However, the view that "digging" is a central skill in doing archaeological research is massively overblown and erroneous. Digging is destructive - archaeologists are the greatest threat to the archaeological record. The origins of such destructive field strategies comes from 1930s interests in stratigraphy for culture history construction as well as putting maximum numbers of individuals to work per the WPA and other Depression-era work programs. The 1x1 meter square, in fact, is a descendant of the 5x5 foot square that was chosen to be large enough to stick a person and a shovel in. The size of the unit has little to do with sampling: it is too big for small artifacts and too small for large artifacts (such as aggregate scale). The array of technology that permits one to study the record w/o excavation (and subsequent destruction) increases daily. Don't drink the excavation Kool-Aid... Even in Mycenean archaeology the practice is pointless, destructive and provides little in the way of knowledge about the record that cant be obtained in other ways. (This means you, Keep-the-table-empty Dude).

One caveat to this point: in CRM in the US there is a strong bias towards digging 1x1 meter holes as a means of bilking developers and lining the pockets of CRM company owners. Digging holes is expensive because of the labor involved and the subsequent activities required to deal with the stuff uncovered. This doesn't mean that much is learned by doing this -- even the best reports of 1x1 meter "test" pits simply state that "some stuff was found" since the samples uncovered have no known relation to each other -- but it does mean that someone is getting rich. Current estimates place the cost of a single 1x1 meter unit at more than $10,000. That's good coin. So my caveat has to do with the fact as a student archaeologist you probably should get your piece of the pie in order to make a living until you can be in charge and change this rip-off. So by all means, learn to dig a 1x1m -- just do it in the cheapest and most expedient way you can that gives you the street-cred to take a CRM position at your local archaeology firm.

Next up: What you do need to know before you start archaeological graduate school.

Tuesday, March 2, 2010

Moai Model

Just a quick followup to my post about 3D printed moai. I received the moai kindly printed by Mark A. Ganter. The actual item is about 8" tall and is a perfect replica of the computer model I created with Photosynth. The texture of it is a bit grainy which is a function of the powder used to generate the object. It is infused with wax to make it more robust. All in all feels like the volcanic tuff used to create the real moai. What is most important, however, is the fact that the details are correct, in particular, the center of mass. All other models made for transport 'experiments' have been based on some basic measurements and a bit of artistic interpolation. This model, on the other hand, is a reliable approximation of the real deal. Thus, when we evaluate ideas about moving the statues, we can get a real "feel" for how an actual moai might respond. Other than Pavel Pavel, the Czech engineer who moved an actual moai and Heyerdahl who dragged one across the beach at Anakena, no other experiment has made use of an accurate model. In general, then, other conclusions have been drawn simply on the basis of weight and size of a big statue-like object. Here, we can really see the limits of motion that reflect those likely present in real moai.

Playing with the model is fascinating. The center of gravity, as measured on the real moai, really is slightly forward which gives the statue a general forward lean. The front edge of the statue is rounded like the real ones and slightly flattened on the sides. Together this means that when you tip the statue slightly to the side (and a small bit forward) it "rocks" along the front edge and takes a step forward. Tipping to the other side reverses the motion and causes another "step." These things really can walk. And it takes just a small bit of energy to do so and is very stable - the shape of the front edge is such that the forward lean turns into a twist. It also means that there is no friction as the surface is not sliding on the ground -- rather the statue rocks along the edge. Absolutely amazing.



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