| Index | Last Week | Contact DQ News | Latest Issue |
| Featured Articles | Data & Information | Science & Technology | Education |
| Economics | Business | Law | Medicine |
What Does the Scholastic Aptitude Test Measure?
The front-page article in the January 10th issue of The New York Times Magazine, examined the influence of the college prepratory Scholastic Aptitude Test (S.A.T.) on American students, their families and American and (some) Canadian colleges and universities. In a culture obsessed with measurement, the S.A.T. has arguably become the single most important test for American high school students. Although recent studies have shown that the S.A.T is only a modest predictor of future academic performance, particularly among students with higher scores, this is little comfort to the two million college-bound students who take the S.A.T.'s each year.
With society more focused than ever on brand names, there is a strong conviction among parents and students that attending a prestigious college confers huge future advantages. While high S.A.T. scores - above about 1300 - do not guarantee admission to the most exclusive schools, low scores can be all but disqualifying. According to the Times, even high schools are increasingly relying on tests like the S.A.T.'s in determining admissions.
Middle-to-upper class parents are also increasingly signing their children up for expensive S.A.T. prepratory courses. Such courses can last an entire academic year and cost $25,000. Those who offer such courses claim that they can substantially boost a student's S.A.T. test scores (in some cases by 300-400 points) over what the same un-coached student would have achieved. The article's focus is on the fairness of S.A.T. coaching vis a vis children from all income levels applying for college. Some parents can't afford any S.A.T. coaching. Some parents and educators ask what the test is really testing when expensive coaching can produce impressive results.
The article doesn't examine other aspects of the Scholastic Aptitude Tests. These include the difficulty in extrapolating S.A.T. scores over decades, when both the test and the population of students taking the test changed significantly. Neither does the article ask whether the S.A.T.'s have outlived their usefulness. The article was written by Tony Schwartz and appeared on page 30.
Digital On-Line Human Dissection - Better Anatomical Data?
A lengthy article in the January 13th issue of The Washington Post explores the consequences of the U.S. Government's 1993 decision to dissect the bodies of a man and a woman into thousands of cross sections. The Government believed that the dissections would form a high-tech digital database, which could be used to provide an "anontomical standard." Two bodies were chosen, from those of about 2 million Americans who die each year. The bodies - of a Texas murderer put to death by lethal injection in 1993 and, in the same year, a 59-year old Maryland woman who died suddenly of heart disease - were first embalmed and then frozen solid. The Government designated the high-tech dissection as the Visible Human Project. According to the Post, the U.S. National Library of Medicine decided to pay for fine-sectioning and photographing two cadavers. Today, more than 1,000 companies and institutions in more than 41 countries have licenses to use information produced by the Visible Human Project for myriad purposes. Several companies are making CD-ROM or Internet-based atlases thsat will allow students to virtually dissect a body layer by layer and isolate structures, such as muscles and organs, and rotate them in three-dimensional space.
From shortly after their times of death, the two bodies were subjected to photography, X-rays, magnetic resonance imaging (MRI), and computed axial tomography (CT). The male and female bodies were subsequently cut into four sections by a special saw and then "milled" by a rotary rasp, which ground down the tissue to a specified depth. In the male, this depth was 1 millimeter. In the female, it was 0.33 millimeter, providing three times as much detail.
Each round of milling exposed a smooth rock-hard surface in which the anatomical features were visible like the grain in a log. The surface was then photographed, using both digital and conventional film cameras, before removal of the next "cyrosection." Each cycle required from three to 15 minutes to complete. The Visible Human male comprises images from 1,829 cross sections and took nearly four months to complete. The visible female is made of images from 5,187 sections and took nearly 10 months. The result was essentially raw data (15 gigabytes for the male and 40 megabytes for the female.) The laborious task of delineating and labeling features (called "segmentation") was done by human anatomists.
Although the Visible Human project was meticulously planned, several improvements in future anatomical projects are contemplated. The male and female bodies chosen in 1993 were on the verge of obesity. The male had several body parts surgically removed years before his death. The female had heart disease. The milling process wasn't fine enough to produce enough detail in some regions of the body. The article was written by Post staff reporter David Brown and appears on page H1.
Data Transforms U.S. - Mexican Border
An article in the January 14th issue of The New York Times surveyed computers and data monitoring systems the U.S. Immigration and Naturalization Service (INS) is installing along the U.S. border with Mexico. The systems are designed to both to speed border crossings and apprehend illegal border crossers.
At border crossings, INS is installing "automated driving lanes." Vehicles in the program are equipped with radio transponders. As a vehicle approaches the border, the license plate number. together with names of the authorized occupants and their photographs, appear on a monitor inside the inspector's booth. Inspectors compare these images with the faces inside the vehicles to seee if there are any imposters. The drivers also swipe an identity card through a reader. A few people chosen at random are interviewed as a precaution against smuggling. This contrasts with long lines at other checkpoints while inspectors interview border crossers and examine written documents.
The INS is using automated identification systems to speed frequent legal border crossers through the border, so the agency can concentrate its resources on illegal border crossers and smugglers. In addition, INS is using various surveillance systems to attempt to prevent smuggling. These range from large X-ray machines used on cargo vehicles to fiber optic cameras to look inside vehicle fuel tanks. INS is also using buried seismic sensors and low-light video cameras at various locations along the border. The article was written by Verne Kopytoff and appears on page E1.
Go to: Data Quality Home Page
Comments: dqemail@aol.com (1999-01-10)