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A team of scientists at the Weizmann Institute of Science has identified a basic principle of communication: How do we succeed in putting our ideas into words so that another person can understand them? This complex undertaking involves translating an idea into a one-dimensional sequence - a string of words to be read or spoken one after the other. Of course the person on the receiving end might not get the point: The effective expression of one's ideas is considered an art.
Physicists and language researchers at the institute in Rehovot recently applied scientific methods to some of our culture's most successful models for effective transfer of ideas - classic writings that, by common agreement, get their messages across well. They created mathematical tools that enabled them to trace the development of ideas throughout a book. The international team included Prof. Elisha Moses of the physics of complex systems department and Prof. Jean-Pierre Eckmann, a frequent visitor from the University of Geneva, as well as postdoctoral fellow Enrique Alvarez Lacalle and research student Beate Dorow from the University of Stuttgart. The paper describing their research was published in the Proceedings of the National Academy of Sciences (PNAS).
Because strings of words are one-dimensional, they literally lack depth. Our minds and memories aid us in recreating complex ideas from this string. The narration "encodes" a hierarchical structure, such as chapter-paragraph-sentence. The implication is that our minds decipher the encoded structure, allowing us to comprehend the abstract concept.
To test for an underlying structure in strings of words known for their ability to convey ideas, the scientists applied their mathematical tools to a number of books, including writings of Albert Einstein, Mark Twain's Tom Sawyer, Metamorphosis by Franz Kafka and other classics. They defined "windows of attention" of around 200 words, and within these windows, they identified pairs of words that frequently occurred near each other (after eliminating "meaningless" words such as pronouns). From the resulting word lists and the frequencies with which the single words appeared, mathematical analysis was used to construct a sort of network of "concept vectors" - linked words that convey the principal ideas.
Mathematically, these concept vectors can go in many directions, so reading a text can be thought of as a tour along paths in the resulting network. The multidimensional concept vectors seem to span a "web of ideas." The scientists say this network is based on a tree-like hierarchy that may be a basic underpinning of language. The reader or listener can reconstruct the hierarchical structure of a text, and thus the multidimensional space of ideas, in his or her mind to grasp the author's meaning. Philosophers have taught that language plays a central role in shaping the human brain, and that revealing the structure of language is an essential step to comprehending brain structure.
"Our contribution to research in this basic field," explained Moses. "A deep question that remains open is if and how the correlations we uncovered serve the esthetics of the text."
ISRAELI CHESS COMPUTER IS TOPS
"Junior," the Israeli chess program developed by Amir Ben and Shai Bushinsky, has won the "World Cup" in the recent World Computer Chess Championship held recently in Torino, Italy. It was Junior's fifth win over the past 11 years.
The computer program faced 18 tough opponents, but at critical moments succeeded it pulling a number of brilliant moves out of its "hat." Only in the last round did it manage to overcome "Shredder" and "Rajlich" by half a point. In 11 games, it won seven and tied four. Before the finals, Junior was ranked in fourth place. It runs on an Intel parallel computer, which is based on 65-nanometer technology.
"Every year, we make improvements in the program," said Bushinsky. "The pogram inegrates computational ability with human characteristics and makes it possible to succeed impressively against competitors."
BARKING UP WRONG TREE
Incessant dog barking annoys many humans, but now US veterinary scientists have discovered that the overwhelming noise of barking at animal shelters causes stress in dogs as well. While employees at animal shelters can wear ear protectors, dogs don't have that option, said Crista Coppola, a veterinary medicine instructor at the University of Illinois.
"Excessive noise in shelters can physically stress dogs and lead to behavioral, physiological and anatomical responses."
Writing in the Journal of Applied Animal Welfare Science, Coppola and colleagues from Colorado State University studied noise measurements made at an animal shelter. "Noise levels regularly exceeded the measuring capacity of our noise dosimeter, which was 118.9 decibels," said Coppola. "These levels were higher than that of a jackhammer (110 decibels)."
A common noise problem in shelters occurs when dogs are placed in gated kennels along the perimeter of a large room. "Dogs are a very social species," Coppola said. "They want to be around other dogs. When they see other dogs but can't get to them, you hear a lot of frustrated barking."