To calculate a problem, you move the discs up and down until you get to a solution. For much of that evening, Stevenson used a practice called "mental abacus," envisioning the abacus in her mind and then using her fingers to work through the problem. From watching Stevenson, I knew that gaining skills on the abacus was more than a matter of counting beads, and so I decided to enroll myself and my two daughters in an abacus course to see if we could also hone our math skills.
Along the way, I learned surprising insights into how people gain new skills. As a technology, the abacus predates the making of glass and the invention of the alphabet.
The Romans had some sort of counting device with beads. So did the early Greeks. Researchers from Harvard to China have studied the device, showing that abacus students often learn more than students who use more modern approaches. UC San Diego psychologist David Barner led one of the studies , and he argues that abacus training can significantly boost math skills with effects potentially lasting for decades. These sorts of conclusions have inspired groups of abacus devotees, and schools devoted to the practice have been popping up everywhere Los Angeles to New Jersey.
My sister, Katharina, counts herself among the converts. A technology teacher in Maryland, she started using the tool to teach her students math a few years ago.
Now she gives abacus workshops and has half a dozen different abacus apps to help her students hone their skills on the tool. When first I watched high school abacus whiz Serena Stevenson, her hand gestures seemed like a pretentious affect, like people who wear polka-dot bow ties. But it turned out that her finger movements weren't really all that dramatic, and on YouTube, I watched students with even more theatrical gesticulations. What's more, the hand movements turned out to be at the heart of the practice , and without any arm or finger motions, accuracy can drop by more than half.
Part of the explanation for the power of the gestures goes to the mind-body connection. But just as important is the fact that abacus makes learning a matter of doing.
Psychologist Rich Mayer has written a lot about this idea , and in study after study he has shown that people gain expertise by actively producing what they know.
The power of mentally doing is clear in memory tasks. This idea also extends to more difficult cognitive tasks. Take something like reading. As an approach to learning math, abacus reduces demands on short-term memory.
This is important because short-term memory is important. Researchers now believe that everything that we learn needs to first be processed in short-term memory before the material becomes stored in long-term memory and thus learned. The problem is that short-term memory is pretty short, and we are only able to juggle around half a dozen items at a time. This explains why we can't multitask while learning. Music, driving, Twitter — they all drag on short-term memory , and thus keep us from understanding.
The abacus appears to have evolved over the centuries to put less demand on short-term memory, and the five beads on each post lines up pretty well with the number of items that people can retain in working memory. In this regard, the abacus provides some important take-homes when it comes to learning.
We often overestimate how much information we can store in short-term memory. More precisely, people often try to learn too much at a time, taking an all-you-can-eat-style approach to gaining expertise. People will think, for instance, that they can learn from a lecture while chatting with a friend. They can't. Or people will try to understand a big, complicated idea in a single sitting. Events often suffer from much the same problem. Long talks, lengthy meetings, and prolonged lectures can all erode short-term memory, crowding the limited pathway to long-term memory.
For this reason, experts such as Ruth Colvin Clark argue that classes should never go longer than 90 minutes. When I interviewed psychologist John Sweller , who studies the role of short-term memory in learning, he gave the example of foreign language programs that try to instruct people in history or literature.
By combining the two topics, people learn a lot less, he argues. Shortly after enrolling my daughters and myself in an abacus class, we discovered that the practice relies on a math strategy known as decomposition , which makes computation easier by breaking numbers down into their component parts. So students are encouraged to think about how certain numbers have "complements" or "partners.
Floating point calculations are performed by designating a space between 2 columns as the decimal-point and all the rows to the right of that space represent fractional portions while all the rows to the left represent whole number digits. Your browser does not support Java. The Java version of the abacus is a limited simulation of the real device because the fingering technique is completely obfuscated by the mouse. Abacus Apps on touch-screen tablets are better simulations.
With a real abacus, constant practice is indispensable in achieving virtuosity in calculating speed. With the Japanese version, only the index finger and thumb are used. The beads are moved up with the thumb and down with the index finger. However, certain complex operations require that the index finger move beads up; e. Each bead in the Upper Deck has a value 5; each bead in the Lower Deck has a value of 1. Use precise geolocation data.
Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. An abacus is a calculation tool used by sliding counters along rods or grooves, used to perform mathematical functions. In addition to calculating the basic functions of addition, subtraction, multiplication and division, the abacus can calculate roots up to the cubic degree.
Abacus is also an academic accounting journal published and edited by the University of Sydney. Before the Hindu-Arabic number system was invented in India in the 6th or 7th century and introduced to Europe in the 12th century, people counted with their fingers, and even their toes in tropical cultures.
Then, as even larger quantities greater than ten fingers and toes could represent were counted, people picked up small, easy-to-carry items such as pebbles, sea shells and twigs to add up sums.
However, merchants who traded goods needed a more comprehensive way to keep count of the many goods they bought and sold. The abacus is one of many counting devices invented in ancient times to help count large numbers, but it is believed that the abacus was first used by the Babylonians as early as 2, B.
When the Hindu-Arabic number system was widely accepted, abaci were adapted to use place-value counting, a system in which the position of a digit in a number determines its value.
In the standard system, base ten, each place represents ten times the value of the place to its right. Since the first abacus, the physical structure of abaci have changed, but the concept has survived almost five millennia, and is still in use today. Over time, counting devices continued to evolve due to technological advancements.
For example, in , the modern slide-rule was invented and it was widely used until when the Hewlett Packard HP scientific calculator made the slide-rule obsolete.
Nevertheless, the abacus is still a trusted tool used by shopkeepers in Asia, and Chinatowns in North America, as well as by merchants, traders and clerks in parts of Eastern Europe, Russia, and Africa. Another popular use of abaci around the world is to teach arithmetic to children, especially multiplication; the abacus can substitute for rote memorization of multiplication tables.
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