For want of a nail, etc.

Some interesting articles in the NYT today on the economics of the earthquake/tsunami in Japan:

Stress test for the global supply chain, by Steve Lohr (3/19/2011)

• "Chain" is misleading, because it really is a network, or a system ("Modern global supply chains, experts say, mirror complex biological systems like the human body in many ways"). Where there is redundancy and resilience, the disruptions are manageable.
  
• "The good news for the world’s manufacturing economy is that the sectors where Japan plays a vital role are fairly mature, global industries." Mature networks have developed redundancy and resilience, and moved away from single source.
• "Still, Japan produces a far higher share of certain important chips like the lightweight flash memory used in smartphones and tablet computers." Even if Japan makes "only" 35% of the flash memory chips, that is still a big chunk of source.
• "The field of buying and shipping supplies has been transformed in the last decade or two. Globalization and technology have been the driving forces. Manufacturing is outsourced around the world, with each component made in locations chosen for expertise and low costs. So today’s computer or smartphone is, figuratively, a United Nations assembly of parts." Attempting to separate "globalization" (as it is meant today) and "technology" as two distinct things is silly -- globalization is a function of new technologies; capitalism in the age of electronics.
• "That means supply lines are longer and far more complex than in the past." Which makes them more tenuous and vulnerable. The term for comlex procurement networks and long supply lines is "thin strands."
  
• "The ability to manage these complex networks, experts say, has become possible because of technology — Internet communications, RFID tags and sensors attached to valued parts, and sophisticated software for tracking and orchestrating the flow of goods worldwide." Exactly -- this is why one can say globalization is a function of technology.
• "'In the past, when you had a disruption, the response was regional,' says Timothy Carroll, vice president for global operations at I.B.M. 'Now, it’s globalized.'” So global supply networks should make it easier for producers to accommodate the Japan disaster.
• Here is the really interesting insight for me: as the supply networks expand and complicate, "the difficulty and expense of seeing deeper into the supply chain increases." (emph. added) The problem becomes determining the impact on the parts used to make the parts, and the parts used to make the parts that make the parts, etc. etc., and even the raw materials to make the parts etc. etc. "For example, reports that a Mitsubishi Gas Chemical factory in Fukushima was damaged by the tsunami have fanned fears of a coming shortage of a resin — bismaleimide triazine, BT — used in the packaging for small computer chips in cellphones and other products."
• "The Japan quake, some experts say, will prompt companies to re-evaluate risk in their supply chains." Rich, deep, redundant, resilient networks as risk minimizers (for more see a thing I did called "Networks and Globalization"). In this case, it might prompt "a shift from focusing on reducing inventories and costs, the just-in-time model, pioneered in Japan, to one that places greater emphasis on buffering risk — a just-in-case mentality."
• Redundancy is one strategy -- multiple sources; resiliency is another -- the ability to quickly develop alternatives in case of emergency.
  

A Crisis That Markets Can't Grasp by Jeff Sommer (3/19/2011)

• How do you price risks that are relatively remote, where there isn't much experience, if any? 9/11, Hurricane Katrina, the BP oil spill, and now the Japan earthquake/tsunami? "So perhaps a bigger question is whether the markets — in which we have come to place so much trust — can put a true price on outsize risks like this."
• “Past performance is no guarantee of future success."
• Nassim Taleb, who popularized the term "black swan" (referring to rare or difficult to predict high impact events) "argues that we have psychological biases that blind us to the enormous role played by rare events — like a 9.0-magnitude earthquake. And yet we rely on history for guidance."
  
• "Whatever else they may be, markets are immensely complex counting machines. They assign values to products, whether computer chips or potato chips, based on the canny appraisals and gut beliefs of people around the planet. From day to day, it is often hard, if not impossible, to know exactly why a certain price moved the way it did. Those daily movements are often just the white noise of global capitalism."
• And then "there are stretches of extreme volatility, periods when no one quite seems to agree about where anything is going."
• And nuclear power... "The financial markets have always had a difficult relationship with nuclear power, largely because the costs — and potential risks — associated with nuclear plants are so huge. Day to day, nuclear power is cheap. But it is unclear how to accurately assess the cost of disposing of nuclear waste over the long run — or, perhaps, the cost of disasters like the one in Japan." Economists, politicians, capitalists may just ignore the externals, the environmental costs, either because someone else (namely you and me, the general public) will pick up the tab, or because it is too complex to calculate, or there isn't enough information to figure it out. "Professor Stavins said, 'You can argue that the markets have never really had a chance to price nuclear power.'”
• "In the face of black swans — also known as fat-tail events, for the way their occurrences are distributed along a probability curve [those outlier events, low probability, but possible, like winning the lottery) — market pricing may be impossible."

The last comments relate to this final article:

Lessons from Chernobyl for Japan by Ellen Barry (3/19/2011)

• The contaminated area around Chernobyl will remain contaminated for more than 300 years.
• "One had to look at Ukraine to understand the sheer tedium and exhaustion of dealing with the aftermath of a meltdown. It is a problem that does not exist on a human time frame."
• An eerie instance of an abandoned civilization: "The wild world is gradually pressing its way in... 'This is a city that has been captured by wilderness,' he [ said. 'I think in 20 years it will be one big forest.'"
• According to one worker involved in maintaining the shell around the defunct reactor: “'Nobody knows what to do with what is inside,' he [Anton Yukhimenko, who leads tours of the dead zone] said. 'There will be enough work for my children and my grandchildren.'"

jd

Diane Ravitch in Chicago

Diane Ravitch, author of The Death and Life of the Great American School System: How Testing and Choice Are Undermining Education and frequent critic of what she refers to as "corporate education reform" spoke to over 400 people on Saturday (March 12, 2011) at the UIC Forum. The event was sponsored by the Chicago Teachers Union.

An iPhone is not the easiest thing to take notes on, but here is an assortment of what I was able to take down. The bits below end up sounding like tweets, and it so happens Ravitch is a prolific tweeter ("I am not on Facebook").

"Is this an age of insanity or an age of stupidity?"

"[Corporate education reformers are ] standing on children to push agenda. School reform as a front to destroy public sector unions."

Referring to events unfolding in Wisconsin and there potential impact on education there, "Where is Arne Duncan? Will Arne Duncan meet me in Madison? Where is President Obama?" And "Money was not the point. -- killing collective bargaining was the real goal.

"We can't let the corporate reformers destroy public education."

"The NCLB mandate [that all students be proficient in reading and math by 2014] is utopian. It can't be met. No country has done it. NCLB is a timetable for the destruction of public education. Private entrepreneurs are waiting in the wings." By analogy, if NCLB was extended to police departments: "If the United States is not crime-free by 2014, close all of the police departments, and give a badge to anyone who wants one."

"The future of public education is in the balance. It is the cornerstone of democracy. It should not be privatized."

Synonyms for Race to the Top:

• NCLB 2.0
• Race to the Trough
• Dash to the Cash

On testing:

• "Testing is not the same thing as instruction."
• "Take test scores with a box of salt."
• "Testing is not a science." Testing is a social construction.
• "Data is just a representation of reality, it is not reality."
• "How can you evaluate teachers on data that is meaningless."
• "We need a broader vision of education. We need tests for diagnostic purposes. But high stakes testing is a corruption of the test."

Poverty is the the problem, not teachers. Where the Harlem Children's Zone (Geoffrey Canada, hero of Waiting for Superman) succeeds, it is because it is an antipoverty program. Poor children arrive at school with an achievement gap already in place. Teachers had nothing to do with that. Education in the United States as a whole is not failing, only poor peoples' schooling.

"Merit pay makes no difference." See work by Daniel Pink and Edwards Deming.

See http://www.saveourschoolsmarch.org/

jd

Computers and chess

I continue to be fascinated by the ways in which computers (and new technologies in general) change the terrain in so many (all?) fields. Dylan Loeb McClain's chess column in the March 5, 2011 New York Times, titled "Still No. 1 in the World, by the Thinnest of Margins", comments on the fact that the world's three top-ranked players are only separated by a range of 9 points (out of 2,800 points). Garry Kasparov, the top-ranked player for 20 years until he retired in 2005, was, McClain notes, was often 30 or 40 ratings points ahead of his closest rival.

What I find of interest is that McClain attributes this to the fact that players today have access to the same databases of games (want to review the Immortal Game? you can find it in any number of places, and step through each amazing move. What about a match between Salo Flohr and Max Euwe, 1932? Yep. Or all of Bobby Fischer's games, or ... see chessgames.com, or chess.com). Plus they have access to powerful computer chess engines to experiment with. And for the average punter, online play can dramatically expand one's board experience. So the tools of preparation are more evenly available: "Today, players have access to the same databases and computers when they train, and native ability is more important than ever" (which is another interesting insight).

Also see this post re: an article by Kasparov on computers and chess.

jd

Wired article on global manufacturing

The latest Wired (19.03) has an interesting article on small to midsize U.S. manufacturers returning production to the U.S.

These days, labor, while an important cost, is often not the critical one to determining where to produce, due to continuing advances in automation and robotics. With China's rising labor costs, currency revaluation and quality control problems, the overall cost of making things in China is getting more expensive. Add in the distance to market and the related travel and shipping costs (still a big factor when moving matter) , producing closer to market is making more sense for many manufacturers.

The article puts this in network terms: the longer and more tenuous the links between the nodes of the global economy, the more fragile the network and prone to problems.

The article isn't on the website yet, but should be in the not too distant future.

jd

3/6/11 update: The article is available online now: Made in America: Small Businesses Buck the Offshoring Trend, by Brendan Koerner.

Solving math word problems

A teacher asked me a question re: strategies for solving word problems. This is what came to mind:

1. Consider the popular 4-step problem-solving strategy (adapted from Michael Polayi, appears in the MathThematics text; there is a good description on the this Scholastic.com page) as an overall approach. The basic steps are:

1. Understand the problem
2. Make a plan (there are lists of basic strategies like "guess and check", "use a formula", "draw a picture"; see the Scholastic link above for a longer list).
3. Carry out the plan
4. Look back (review, reflect, evaluate)

2. As part of step 1, understanding the problem, Ms. Schumacher at our school has students mark the problem text in different ways to isolate the key parts of the problem. She has her students underline the portion of the problem that says what to do, or what the question is asking for. They circle numbers or number words that are important to the problem. And they draw boxes around the actions they need to perform on the numbers (see next point). Reading math problems is a kind of literacy, and this deconstruction of the text can help comprehend the problem.

3. Again related to step 1: Since reading math problems is a kind of literacy, students need to understand the vocabulary of math. There are addition words, subtraction words, and so on for each basic math operation. For example, addition words are words like "sum", "plus", "add", "increased by". Subtraction words are words like "less", "difference", "decreased by". Being able to recognize key math words, and what operations they are calling for (as well as what order to put the operands in) is important. Purplemath has a table of "key words". Here is a link to a table students and I put together last year. (It is also important to be able to determine what is important information for solving the problem, and what is extraneous or irrelevant information).

4. Students have different skill levels when it comes to what strategies they might use, but it might be useful to reinforce that a strategy that works is a good strategy, the main trade-off being effort to arrive at a solution. Guess-and-check (or using "brute force") is okay if you have the time and patience; algebraic methods are very flexible and powerful but may be prone to error if the student isn't comfortable with them. It is also important I think that students recognize that a combination of strategies is frequently used (e.g., I find it useful to first draw a picture or diagram, or make a table, to understand the problem before thinking of an algebraic solution).

5. The last step is very important. Is the answer reasonable? Does it actually solve the problem? Was there an easier way to tackle it? Will it work for other problems?

6. Regarding teaching strategies:

• Whatever can be done to help students de-code the problem can help. I am thinking of comprehension strategies used with other kinds of texts.
  
• A think-aloud of how the teacher might approach the problem could model the problem-solving strategy for the students.
  
• After students have highlighted the key parts of the problem (what the problem is asking for, the key numbers, the operations), modeling how to put the pieces together can help.
  
• A KWL chart might structure the process, especially if students are familiar with the format. The Know part, "what do we know already?" = the numbers and operations that the students have highlighted. The Want to know part = what the problem is asking for. The Learned part is the problem solution.
• Having students make up their own word problems for other students might help them understand the structure or genre of math word problems.
• Writing in a math journal about what they did to solve a problem might help gel the process for them.
• Re: thinking about general problem-solving strategies, posing practical problems for the students might build their confidence in their problem-solving abilities and connect with strategies they already use, but don't think of them as such ("activating prior knowledge"). For example, a million dollars is waiting for you at the Lincoln Park Zoo -- how are you going to get it?
• Having a context for understanding a word problem is important. If the problem deals with things the students don't know anything about, it is hard to understand what the problem is asking. This starts to slide into the area of math and social justice -- presenting math in terms that connect in deep ways with the lives of the students. Students need to be engaged enough with the material to want to solve the problem.
• There are lots of other words that have math meanings, separate from different ways of referring to the basic operations and relations. See the ISBE Math Frameworks Glossary for words and definitions that are important to know when approaching word problems.
• Being able to talk to students about how they solved or didn't solve a problem can be very useful for understanding their thinking and the source of possible misunderstandings.
  

This just touches on some strategies. Any comments are welcome. Literacy Strategies for Improving Mathematics Instruction, by Joan M. Kenney et al. (an ASCD book) has insights into different aspects of math and literacy.

Since most real-world problems that require math present themselves as word problems, I think it is important that students are fluent in translating them into math terms, and using math tools for finding solutions. It is one of the important ways that math becomes meaningful.

jd

The Best Classrooms

I saw a reference to the article below in a mailing from The Alliance for Childhood (more play!):

Brilliance in a Box: What do the best classrooms in the world look like?

The title of the article (by Amanda Ripley, and appeared in Slate) pretty much sums it up, but there are a couple of stand-out lines:

"Classrooms in countries with the highest-performing students contain very little tech wizardry, generally speaking."

"'In most of the highest-performing systems, technology is remarkably absent from classrooms,' says Andreas Schleicher, a veteran education analyst for the Organization for Economic Cooperation and Development who spends much of his time visiting schools around the world to find out what they are doing right (or wrong). 'I have no explanation why that is the case, but it does seem that those systems place their efforts primarily on pedagogical practice rather than digital gadgets.'"

"But the most innovative schools around the world do not tend to be the ones with the most innovative technology inside them."

There are other observations about what may be making schools successful -- pedagogical skill, parent involvement, length of school day -- no great surprises there. The technology aspect, though, was the standout for me.

jd

Making Khan Academy-type lessons on the iPad

I like, very much, the spirit of the Khan Academy videos (free!), and the content too (1800+ per the website, and growing). They are also available on the iPhone and iPad. If you have never seen them, they are basically screen captures of Sal Khan writing on a computer screen, with narration of what the instructor is doing. According to the site, this is how he does it:

I use Camtasia Recorder ($200) + SmoothDraw3(Free) + a Wacom Bamboo Tablet ($80) on a PC. I used to use ScreenVideoRecorder($20) and Microsoft Paint (Free).

I wanted to see if I could make the same -- creating something specific to my class, using my Mac, without buying anything new. I have an iPad, a MacBook, and am playing around with Apple's relatively new Magic Trackpad. Seems simple enough, right?

The Magic Trackpad didn't work very well as a drawing tablet. The Pogo stylus I have required a lot of pressure to draw with. Fingers were okay but it seemed unnatural, and difficult to simulate the click-drag combination required to draw with a mouse (which I find equally difficult to use to write legibly). The trackpad works well as a mouse replacement, but it really isn't a drawing tablet.

The iPad is a great tablet platform. Adobe Ideas, for example, has nice line-smoothing drawing ability, and with a stylus, it is very easy to draw legible handwriting (like Khan!). Plus, the iPad has the audio recording hardware, and an app like PaperDesk includes both drawing tools and recording tools. However, there is no sanctioned way to capture video of the iPad screen from what I can tell (single frame captures are part of the iPad OS, press the home and power buttons at the same time). There is software for jail-broken iPads (ScreenRecorder + FullForce) to record the screen, but I'm not ready to jail-break my iPad.

Another approach is to display the iPad screen on the Mac. You can use something like Veency on the iPad (a VNC server), and record that portion of the Mac screen, but again, this requires a jail-broken iPad. Another way to get the iPad video signal to the Mac, without jail-breaking is to use a converter from Epiphan, but it lists for $299.

An app like Whiteboard, which allows you to share whiteboards with other iPad users, would probably work if there was a Mac version of Whiteboard (and so capture the Mac version of the Whiteboard using screen recording software on the Mac).

My current, albeit crude, solution, is to use a web-based whiteboard-sharing software, GroupBoard (free for up to five collaborators). Groupboard has an iPad app (free). I created a shared online whiteboard by creating a page on a site I manage, and included the one line of HTML that Groupboard provides. On the iPad, I logged on to the Groupboard whiteboard I set up. I did the same using my browser (Firefox) on the Mac. On the Mac, I used iShowU HD ($29.95) to record the activity on the screen, in this case capturing what showed in Firefox. I used the built-in microphone on the Mac to record the narration (the sound recording was handled by iShowU as it recorded the screen activity). I used my Pogo stylus to draw on the iPad, and narrated as I drew. Here is the result:

Khan Experiment 1 from James Davis on Vimeo.

It worked pretty well. The handwriting is rather blocky on the shared whiteboard, but passable. Groupboard has a text tool which I used for the title. Unfortunately, the controls for the Groupboard app are on the bottom of the screen, so it is easy to rest my palm on the buttons when drawing and accidentally select the settings options (but this doesn't show on the video because only whiteboard drawing is shared to the Mac). The Groupboard app crashed when I tried to change the text size and line width, so I just avoided those.

The challenge of talking coherently while drawing at the same time and managing the drawing application tools is a real skill, and makes me appreciate all the more what Sal Khan has achieved. I blather on a bit at the beginning, before drawing anything, so patience.

jd

P.S. I would love to hear of other ways people have done this on the Mac, and especially with an iPad.