Thursday, November 28, 2013

The Eyres of London: an enthralling look at crime in the 13th century

I'd like to share with you 13th century court records with all the sizzle of a modern scandal-sheet.

During the 13th century, London's population was roughly 50,000. This was quite a respectable city size for the time, but did not allow for the elaborate machinery of justice we take for granted today. Instead, complaints were filed with the local sheriff or bailiff and prosecution was put on hold until the next time the circuit judge came around. These traveling circuit courts were named 'Eyres' (yes, just like Jane Eyre - her last name is no coincidence).

Most records of 13th-century Eyre trials and judgments are presumed lost, but two have survived in a remarkably complete state. These are the Eyres of London for 1244 and 1276. They were special in that the king himself (or his direct representative) sat in on the judgments. Being therefore the most perfect or official of trial records, multiple copies of the Eyre transcripts were made and distributed as exemplars to judges and other agents of law enforcement. They may be thought of as a bundle of sample cases and precedents with a royal seal of approval.

Copying was not the most reliable of arts at the time, and different surviving copies of the Eyre transcripts vary in details. Fortunately, in the 1970s a British scholar, Martin Weinbaum, took it upon himself to examine all the variations and from them (hopefully) reconstruct the original. His editions of the Eyres were published by the London society, and a hypertext version has recently been made available free of charge at the British History Online web site.

Not only did this scholar scrupulously edit the texts, but he also provided modern English translations alongside the original Latin. It's been over a decade since I last used my Latin lessons, but his translation seems to me to be accurate and conservative.

The London Eyre of 1244
The London Eyre of 1276

I must admit I found these quite by chance. As a student of economic history, my first thought when being asked to find a primary source that could inspire a piece of fiction was to go for probate records. These inventories of items left at a person's death are used frequently by economic historians, and are often heart-breaking or stirring. Entries such as, 'Wooden chest, worm-eaten, containing sheets of fine French cloth, never used. One reserved as burial shroud.' are not uncommon. (Rather reminiscent of the famous six-word novel, 'For sale: baby shoes, never worn.', isn't it?)

Finding well-catalogued, free probate records in English - or in a pinch, grammatically correct Latin - proved easier said than done. A hyperlink chase across a dozen web sites eventually led me to British History Online, where a mis-click took me to a transcript of one of the Eyre sessions.

I didn't leave the computer for a half hour after that. I was hooked.

London, as I mentioned above, had a rather small population. Because of that, personal cases that in another age would never make it to the ears of the head of state were presented to the king. Legal language had not yet calcified into its modern passive voice and restrained, careful neutrality. The court scribe recorded events quite conversationally, and as a result, the stories almost write themselves. All that's needed is putting meat and skin on the skeleton provided, and furnishing entertaining and plausible answers to the questions raised.

Consider the following entry, from one of the first sessions of the 1244 Eyre:

They say that on the feast of St. Ethelburga [11 Oct. 1226] Emma, daughter of Walter of Coggeshall appealed Gregory, son of master Gregory the Physician, of violently raping and deflowering her, and Richard, son of Thomas the Imagemaker of aiding and abetting him. Gregory and Richard come, but Emma does not, and she found pledges to prosecute her appeal, viz. Richard the Baker and John of Kennington, baker. Therefore they are in mercy and Emma is to be taken into custody. Afterwards the mayor and citizens were asked whether they were of opinion that peace had been made between the parties, and they said upon their oath and in the faith in which they are bound to the king that they had agreed together. Asked further if they believe that Gregory is guilty of the deed, they say that he is not guilty. They say also that he who was appealed for aiding and abetting has not made peace and is not guilty. Therefore he is quit. And Gregory is to be taken into custody. He made fine in half a mark, because he is poor, with Simon fitz Mary and John de Coudres as bis sureties.

First of all, note the date: the event took place in 1226, but was not heard until the Eyre of 1244. This is what I referred to above: cases were kept in cold storage until a judge errant arrived. It was common for the parties involved to die before the case made it to court. This led to entries such as this one, from the first case in the above link: "Stephen has died, therefore nothing from him."

The accused was the son of a physician. This raises interesting questions - did Gregory's father know of his son's activities? Did the accused use his father's position to gain access to Emma? Even if he did, apparently he still needed the help of Richard, son of an image-maker. I haven't looked it up, but I suspect this refers to religious images, such as figures of saints in a cathedral. Could Richard have used his father's professional contacts to lead Gregory to Emma when she was alone in prayer within an isolated chapel?

The accused and his accomplice made it to court. Emma, though she was still alive, did not. What was it that made her stay away from the proceedings? Did she fear for her life? She did appoint two bakers as her representatives. At the time, most homes took their dough to the neighbourhood baker, to be baked in a communal oven (for a fee). Suppose Emma kept mostly to herself after the assault. There is no husband mentioned, or children, or change of name - spinsterhood seems probable. If that were the case, she'd seldom leave home and meet other people... save for daily errands, such as fetching water from the pump and baking bread. While waiting for the bread she would have had time to socialize with and get to know the bakers in a safe setting, where she was surrounded by other women. That would explain why these were the men she trusted to represent her at court. Their profession is doubly interesting when we consider that bakers at the time were thought to be proverbially dishonest, adulterating flour with any sand or sawdust at hand. The modern equivalent would be to send two used car salesmen to vouch for her.

The court didn't think the bakers were an appropriate substitute. Gregory and Richard were granted mercy (a kind of conditional bail), and officers went off to arrest Emma - and presumably drag her back to court by any means necessary.

We don't hear any details of testimony by the principals in the case, if indeed there was any. The court was satisfied with conducting something halway between an opinion poll and a jury trial. The answer by the makeshift jury, consisting of the mayor of London and vague 'citizens', seems a bit contradictory. Gregory had 'made peace' with the court, which essentially meant he agreed to stop hostilities. He was found not guilty, but nonetheless taken into custody and charged half a mark, which he could not afford. Two others, presumably his friends, had to promise to pay it on his behalf. This odd juxtaposition of a 'not guilty' verdict combined with custody and a fine suggests that there was a plea bargain: I suspect Gregory agreed to 'make peace' and pay his fine as long as he came out of it without being officially labeled a rapist. While I'd have to research the issue, it's reasonable to think that there were social and religious costs to such a label quite apart from the law's punishment. Meanwhile, Richard the image-maker's son wanted nothing to do with the case. He refused to make his peace, but he wasn't found guilty, either. I can almost see him storming angrily out of the square, pushing people aside while muttering curses under his breath.

This is just one of many, many colorful stories in these wonderful source-books. In the next few weeks, once I've had a chance to read them more carefully, it is my intention to write up a few of them as short historical fiction. Care to join me?

Monday, November 25, 2013

An experiment in personalized learning


(Note to those reading this as part of their Blended Learning assignment: the introduction is meant to provide context for a general audience and may safely be skipped.)

Introduction


Many of us - certainly those reading this blog post - live in a world of information overload. Facts are no longer as dear as they once were. An internet connection provides instant, searchable access to a great part of human knowledge.

The ability to search the internet selectively quickly transforms into the need to do so. A Google search for 'sloths' returns 898,000 hits. That is far too much information to take in, and a selection criterion is needed - a rule whereby some relevant sites will be accessed, and others discarded. Perhaps we're only interested in videos of baby sloths, or academic articles on their digestive systems.

Selection implies context, and context implies personalization. In one context, sloths may be seen in terms of their position in the hierarchy of cuteness. In another, they may be viewed as nothing but host environments for intestinal bacteria.

This context will have been chosen to enrich a particular world-view - an illustrator of children's books in our former example, perhaps, or a microbiologist in the latter. This is personalization.

The particular circumstances of a seeker of knowledge inform the context in which they place facts about the world around them, and this context shapes the selection criteria used to access this information in a way that makes sense to them.

The role of the teacher is changing. Not overnight, and not completely, but it is. For many years the archetypal teacher has been the 'sage on the stage' (as phrased by a course I reference below). An experienced adult with appropriate qualifications hands down information from the lecturer's podium to a student audience. Lectures proceed with the calculated regularity of a locomotive. Students must follow along at the prescribed pace or be left behind. There are extra readings, assigments, quizzes and exams to extend learning beyond the lecture hall, but these are almost always of a one-size-fits-all nature. Even the best-meaning teachers and lecturers seldom have the time to provide their students with customized exercises tailored to their characteristics.

There is some value to this paradigm. When information was costly and difficult to obtain, it made sense for a specialist to collect it on behalf of the students, then feed it to them in a partially digested form. This is similar to how parent birds feed worms to their hatchlings, or how a bee collects pollen and returns it to the hive.

As information becomes abundant and easy to access, the importance of this role diminishes. Anyone with access to a web browser can retrieve information - too much of it, in fact. The expert's role then shifts from the 'sage on the stage' to the 'guide on the side'. The value added from a real live (or pre-recorded) instructor is in giving a guided tour of the neighbourhoods everyone is free to walk through, imbuing them with structure, sense and meaning.

The same technology driving this shift - web search, social networking, interactive applications and so on - also makes it possible for learning to be customized to a student's characteristics and potential to a remarkable degree.

In what follows, I will take you on a tour of a small first step into this new 'blended learning'. The experiment was a small one, done cautiously, which makes it admirably suited as an introduction to the possibilities unlocked by this new way of thinking about learning.

Preliminaries

A preliminary disclosure: I've taken a number of free online courses through Coursera, both for professional development and out of curiosity. One of the most rewarding has been Blended Learning: Personalizing Education for Students.

As their final assignment, teachers taking the course were asked to implement blended learning in their classrooms, then film a short video about their experience. Those without a classroom or video recorder (such as yours truly, for now) were asked to write a blog post about one of the student videos, reporting on the experiment as thoroughly as if it had been their own.

After viewing a number of student submissions, I decided to share with you Grace Dorrington's video. Her narration is exceptionally clear, and the changes made in her school were basic enough to serve as a good introduction to blended learning for someone previously unacquainted with the subject.

The main event

Before we begin, you may want to watch the video I'll be writing about. It's short, insightful and the narrator has a lovely accent.

All done? Great. Let's begin.

I'll follow the Economist style guide in calling people what they wish to be called, and refer to the video's author by her YouTube handle, graced05.

First things first

The school in question started out as a fairly traditional one. Teachers lectured at a blackboard, students listened and took notes. While there was an information technology component to teaching, the online learning software was not used to its full potential. It was essentially a virtual bookshelf - the cheap plywood kind - used to store documents.

There wasn't anything wrong in particular with the traditional style used at the school, but there wasn't much right with it, either. Students muddled through as they have around the world for decades, learning their lessons but not being terribly engaged or excited.

Teaching followed the one-size-fits-all paradigm, which worked about as well as Walmart stocking only medium-sized clothing. The same lessons that some pupils found too loose, others would find suffocating.

Two things stood out as candidates for improvement: student engagement with the material, and somehow allowing education to be customized to student needs, abilities and background.

Risk and Reward

The major change implemented by graced05's school was sensible, simple and effective. They replaced their aging learning sotware with Desire2Learn, one of the new generation of learning management systems.

By going with a well-known third-party application, the school reduced the risk involved in switching software platforms when compared to, say, a custom application.

Desire2Learn is well-reviewed. I do not mean that it has uniformly positive ratings - opinions of this platform are notoriously mixed - but that there are a lot of reviews from teachers around the globe spelling out exactly what they liked and what they did not like about the program.

The accumulated experience of thousands of vocal reviewers allows adopters of Desire2Learn to know exactly what they're getting into. If the negative reviews all mention aspects of the platform that are not important to the school in question, then the system will be superior in this case to what the raw average review score (3.2/5 on one site) suggests.

Before implementing the change, graced05's school made sure to upgrade their technology's infrastructure, further reducing the possibility of something going wrong.

What changed?

In bullet point form, here are a few of the changes made possible by the new software:

* Contextualized resources - Instead of having course web sites be virtual Sanford and Son junk piles, teachers have been placing resources in their appropriate context.

The economics web page at 1:31 in the video, although fairly rudimentary, nonetheless postions links, pictures and a video in a context that makes their relationship to the topic under discussion clear. This small change tests the waters of the 'guide on the side' paradigm mentioned above.

* Conditional release of course information - Desire2Learn allows for content to be gated by skill. In the traditional model, students are assumed to progress through the material at the same pace (barring repeating a year). Mastery-based learning, of which this is a trivial instance, only allows students to progress to the next level once they have demonstrated sufficient skills in previous levels.

Students who show facility with the material will be able to zip along quickly, where in a traditional class they may have been bored through having to wait for others to catch up. Similarly, students who may have had trouble advancing at the one-size-fits-all speed can now take more time to learn material they have difficulty with.

This is very similar to the way in which traditional side-scrolling video games (famously, Super Mario Brothers) gated content. In general, a player could not advance to level 2-3 until they had sucessfully completed level 2-2. Appropriately enough for our analogy, players who put extra work into research or exploration of the levels
could be rewarded with the discovery of secret 'warp zones' that allowed them to bypass a significant amount of content.

Based only on anecdotal evidence, I suspect that familiarity with the video game 'beat the level' trope has led students to greet this style of gated content with acceptance rather than frustration.

* Customized (if canned) feedback on quizzes - Until quite recently, I looked down on multiple choice tests and thought them inappropriate in almost any serious course. Taking a few Coursera courses have changed my mind. Modern learning management sytems allow the creation of multiple choice quizzes in such a way that they make a valuable complement to long-answer tests.

In a new-style test, the multiple choice answers are not arbitrarily chosen to look convincingly like the real answer (e.g. (a) 0.12 (b) 0.11 (c) 0.13). Instead, best-practice test designers consider all the common mistakes that a student could make when answering a question, and turns that solution into an answer.

When a student chooses that answer on the test, chances are they made the mistake in question, and appropriate, customized feedback can be given.

Consider a question that asks you to calculate (5 x 4) + 2. A student uncertain about how to use brackets may answer (b) 30. An example of possible feedback is 'Remember that you have to solve the operations in brackets first.'

Although this way of writing multiple choice tests requires more effort from the instructor, the result is a personalized learning experience that provides useful, valuable feedback. For an example in the video, see the screenshot at 2:05.

Debriefing

In this experiment, a fairly small change in structure - implementing an updated learning system - has led to a sea change in how learning, students and teachers are viewed.

In the videographer's own words (2:55), "Though they're still a vital part of ... education, teachers are no longer the only gateway to knowledge."

The adult teachers have had to readjust in their roles, shifting focus from feeding information and seeing it is properly digested to taking the students on a tour of the orchard. The students still end up full and satisfied, but now they climb the trees that most engage them, and pick the fruit that's most comfortably within their reach.

It will take time for things to settle down to a new steady state. Teachers will have to continue thinking as 'guides on the side' and how best to meet the needs of individual students with the available resources and techniques. The rudimentary state of the course sites featured in the video suggest that despite a promising start, there's a long way to go.

Students, meanwhile, will have to understand that they are now in large part responsible for the pace at which their education progresses. For all that this can be liberating and exciting, it can also be a bit scary. Not only that, but interstudent social relationships are bound to change. Where once students in a class were certain to share identical course histories (assginments, readings and so on) now there is no such guarantee.

Pupils will still make friends at school, of course, but the nature of those friendships will be changed at a basic, subtle level. This interesting adjustment will probably happen fairly quickly, if it hasn't already. Teachers have years of training and experience to make them set in their ways. Students join the classroom with a beginner's mind.

That's it for our guided tour of a blended learning experiment. See y'all Thursday, when we may or may not explore the seedy side of macroeconomic subsidies and strategic investment in utilities.

Thursday, November 21, 2013

PSA: Bitcoin is neither a currency, nor harmless


Disclaimer: my views on currency are not representative of those of most economists. For the sake of clarity, I write as if my opinions were authoritative, but I encourage the reader to question them.

Bitcoin, often described as a digital currency, is swiftly gaining popularity and media coverage as a possible alternative to the fiat currencies issued by national governments.

A Bitcoin is produced by having a computer perform an intentionally difficult mathematical calculation. When the calculation is complete, a Bitcoin is created. The difficulty is meant to keep Bitcoins scarce, and thereby endow them with value.

A fiat currency, such as the Canadian dollar, is usually endowed with value by law that guarantees its acceptance for the settlement of debts within a country. Typically, the government has a monopoly on the production of currency. While some small countries outsource the production of actual coins and bills, the basic point stands.

Bitcoin works differently: anyone with time and a computer capable of performing the calculations can 'mine' them.

It is no secret that from a historical standpoint, governments are almost guaranteed to abuse their power to create currency.

Temptations include printing money to pay bills or sweeten a re-election, limiting the money supply for reputation reasons and using the money supply as a tool to perpetuate an elite's political power and/or otherwise unsustainable economic policies.

Misuse of currency can lead to real devastation - see Zimbabwe's recent history.

I am sympathetic to the desire to get away from all this and switch to a currency that governments can't (easily) tamper with.

Unfortunately, Bitcoin isn't the answer. It isn't even a currency, and the economic misconceptions it is based on can have perverse and harmful, if unintended, consequences.

When we use a national currency, there is an expectation that we will be able to exchange it for almost anything we should need or want - even foreign goods. This is often true even if the currency is very poorly managed - we'll just need more of it.

Why is this possible?

Few things are as certain as taxes. Governments typically require that at least a portion of taxes be paid for in the national currency. Every tax-paying entity in the country therefore has a demand for the country's currency, because they'd like to avoid being jailed for tax evasion.

A fiat currency is therefore backed by the entire tax-paying productive capacity of the issuing country. If the world at large is fond of maple syrup, then the Canadian dollar will have value because Canadian producers of maple syrup will exchange at least some of their crop for the currency.

This is why a fiat currency doesn't need to be backed by gold, or silver, or anything else. If the country produces gold, then it's already backed by gold (though not at a stable guaranteed rate). It's also backed by falafel, painkillers, cleaning services, computers and anything else sold or created by a tax-paying business.

The value of fiat currency doesn't depend on the government requiring it for taxes - that's just one example of many that I chose because it's easy to explain in a few sentences. I leave it as an exercise to the reader to find others (a quick web search will yield a few).

Once you have at least a few entities accepting the currency no matter what, acceptance tends to snowball. Why does your friendly neighbourhood drug dealer accept Canadian dollars if she doesn't pay taxes? Because she can walk over to a convenience store and exchange them for candy.

(Note: lots of Canadian drug dealers and producers actually DO pay taxes - Canadian tax forms allow for paying taxes on income from undisclosed sources. No one wants to be the next Al Capone - a criminal mastermind finally brought down on tax charges.)

If the Canadian government made a mistake and accidentally quintupled the supply of Canadian dollars overnight, they would still have value. You could still exchange them for maple syrup, you'd just need a lot more of them (once prices changed).

Now, to Bitcoin. Why does Bitcoin have value?

Its creator, as interviews show clearly, thought currency had value primarily because of scarcity. Rare things have value. He figured that if he designed a way for Bitcoins to always be scarce, that would guarantee their value.

Fair enough. That doesn't make it a currency, though, that just makes it a scarce good.

The toenail clippings of registered nurses are also scarce (and actually collected for a few research applications), but that doesn't make them generally valued, or something you'd take to the fast food joint to trade for poutine.

National currencies have value largely because we can trade them for stuff we want. This, in turn, is because there's always a currency accepter of last resort - the issuing government. If worse comes to worst, the Canadian government itself will always accept Canadian dollars in exchange for, say, a parking ticket.

Who's the accepter of last resort for Bitcoin?

No one, as far as I’m aware. If I’m wrong, then whoever it is stands up and promises to trade Bitcoins for real stuff (like pizza or software) no matter what and forever is being a bit silly. They run a very high risk of being left holding the bag if there’s ever a crisis of confidence in the market.

While a number of businesses - not all of them illegal - currently accept Bitcoin, there's nothing in place to keep things that way. (Bonus link: a university recently started accepting Bitcoin tuition payments.)

That's why Bitcoin is not a currency. There's no expectation of being able to trade it for almost anything you might need or want.

Store credit coupons such as Canadian Tire money are closer to being currency, because the store will almost always trade them for real stuff.

They're still not currency, though - you can't easily trade a hardware store’s store credit for rice or soap.

One of the things that makes a national currency special is that if a nation's citizens are alive, then by definition everything necessary for life is available in the country. Most or all of these necessities are typically available in exchange for the national currency, in both legal and black markets. (There are exceptions: during periods of hyperinflation, producers and merchants may insist on payment in more stable, ‘hard’ currency.)

Suppose that these problems went away, and tomorrow everyone started accepting Bitcoin.

Bitcoin would still be a bad idea, simply because of the way it's produced.

To produce a Bitcoin, you need to intentionally waste a scarce resource: computing capacity. The mathematical problems solved are difficult, but they're also intentionally useless.

Bitcoin is created through the virtual equivalent of digging holes in the desert and filling them up again. While the activity itself is completely useless, it wastes labour, shovels, water, transportation and so on.

Earlier this month, a technology company sold $3 million (US) of Bitcoin mining equipment in four days.

That's 3 million dollars - more than you'll probably ever earn in your life - being spent on machines devoted to solving useless problems. Three million dollars that could have been exchanged for just about anything on the planet, including malaria research, legal aid for women at risk, and so on.

As an economist, I'm trained to think about the efficient allocation of scarce resources among unlimited needs and wants. From this point of view, the method for creating Bitcoins is obscene. I struggle to find any perspective from which it is morally justifiable - maybe one of my readers can help me with this.

As if the waste of computing resources isn't bad enough, the mining method also creates perverse incentives. In a recent example, mobile game developers are pondering hijacking their players' computing capacities to mine Bitcoins for them.

Even if this is agreed to by the players, you're still slowing down useful machines in order to solve useless problems.

The situation isn't hopeless. There's at least one way to make Bitcoin more palatable: turn it into a reward for equally difficult, but useful computation.

Lots of basic research - gene-sequencing, parsing astrophysical data, brute force molecular pharmacology and so on - require a ton of computer power. Some researchers already farm out their calculations to volunteers. The most famous example is probably the SETI@Home program.

If Bitcoins were rewarded for crunching THESE numbers, then it could actually benefit society.

It would also partially solve the 'accepter of last resort' problem. An academic organization using Bitcoin miners for gene sequencing, for example, could accept Bitcoin payments for access to academic articles and databases that usually require payment in hard currency.

(Aside: it is true that by providing an incentive to solve mathematical problems that are currently difficult, Bitcoin mining encourages innovation. That is also why the technique could be usefully harnessed for the improvement of basic science by being applied to the solving of difficult problems that are also useful and relevant.)

Thus ends my PSA. In its current state, Bitcoin is not a currency, and is harmful. With any luck, this'll change, but for now, don't buy into the hype.