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Home 'Body Fat' Testers - Wide Range of Readings
A report in the December 24th issue of The New York Times compares measurements of inexpensive home body fat testers - devices that measure the proportion of fat in the human body. According to the Times, so-called "home body fat testers" provide a wide range of readings, indicating that the person using them may be thin or obese - depending upon a number of variables like the timing of the test.
The home body fat testers that were tested by Times reporter Kris Goodfellow were priced under $100. They measure body fat by sending low-voltage electric current through one's body, and measuring how much body tissues impede the flow of current. Unfortunately, such devices require precise test parameters, and, even then, provide a wide range of body fat readings. Some of the many parameters that affect their readings are height, age, weight, athletic ability, and sex.
After attempting to determine the amount of fat in her body with low-cost testers, the reporter was tested at the Body Composition Unit at St. Luke's-Roosevelt Hospital Center in New York. The the reporter/patient underwent tests that ranged from a simple pinch test to a sophisticated low-radiation x-ray scan. The hospital tests indicated that the reporter's body was about 20% fat. Both the U.S. National Institutes of Health and the U.S. National Institute of Science and Technology have tested home body fat testers. The accuracy of the devices ranged from plus or minus 1% to 20% of the actual value. The article appeared on page E6.
EPA Inspector General Finds DQ/IQ Problems
According to a report in the December 28th issue of The Wall Street Journal, U.S. Environmental Protection Agency investigators have discovered fundamental weaknesses in a major air-pollution control program that have allowed many "significant violators" to escape inspections and violations for years. According to the Journal, recent reorganizations within the EPA helped generate a serious lack of federal oversight over the program that monitors factories, utilities, and stationary sources of pollution.
The Journal article interviewed EPA Inspector General Nikki Tinsley. She claims her office doesn't have adequate records of the nation's air polluters. "Without that baseline data, you don't have a foundation for the program," she said. The IG audits, conducted in different areas of the United States, show that for several years, state environmental agencies substantially underreported local Clean Air Act violations. Moreover, some states have apparently been able to keep violators off the EPA's list by working informally with the EPA while the states brought violators into compliance. The EPA's Inspector General auditors found that state environmental agency employees made slapdash inspections that produced reports with few details. The states, on the other hand, have asked the EPA for consistent definitions of terms like "significant violator."
According to the Journal, the deficiencies in the EPA's oversight activities have caused concomitant data quality problems for both the agency and the states. The article was written by Journal staff reporter John Fialka and appears on page A16.
Historians Using More Data....Leaving Readers Yawning
An analysis and appraisal of professional historians' recent work appeared on the "OP-ED" page of the December 30th issue of The New York Times. Written by Yale historian John Demos, the article attempts to reconcile the elegant writing style of historians like Edward Gibbon and Francis Parkman with a profession that is increasingly focusing on data.
According to the Times, a broad range of interpretative techniques - including quantification and various forms of applied social theory - has steadily transformed the day-to-day practice of historical scholarship. While entire classes of people whose daily lives were almost unknown have come into view, the article's author complains that the quantification comes at the expense of fluent explication. In the author's view, it's great that the daily lives of groups like slaves, immigrants, factory workers, and college students can be reconstructed from records. But historians aren't doing a good job of translating facts into discourse, according to Dr. Demos. Moreover, today's historians must make difficult choices when translating facts into narrative. They must judge how much contribution an individual made to historical events. They must determine where data about historic events end and speculation begins. And they must resist "fictionalizing" history, while writing a good narrative account of actual events.
Unfortunately for professional historians, novelists are currently writing "historical fiction" that is at or beyond the boundary of history and fiction, based upon data that historians have discovered. Dr. Demos's article doesn't express concern about the quality of historic data. The article appears on page A23.
Computer-Collected Data Assist Winemakers
A report in the December 31st issue of The New York Times examined the widespread use of industrial process-control and agricultural data to assist California winemakers. According to the Times, computers are now collecting data in the sky above California's vines, in the earth below the vines, in the fermentation tanks, and on the wine presses that squeeze the grapes. Throughout California, computer-collected data is used to develop excellent wines.
Although winemakers like to preserve the image of handcrafted wine, data collected by computers are essential to the winemaking process. Technology has helped eliminate flawed wines by helping vineyard owners reduce the wines' variability and less than desireable characteristics. Growers use measurements from several sources, multispectral images taken by aircraft flying at 15,000 feet, soil moisture content, soil nutrient content, pruning records, and taste tests.
Winemakers are also using industrial process equipment to make winemaking less labor intensive and provide a more uniform product. For example, many larger Napa Valley winegrowers use temperature sensors in the tanks and vats where grapes are turned into wine. Variables like the pressure at which presses squeeze grapes are carefully controlled. Formerly laborious tasks like removing sediment from bottles of sparkling wine have been automated. The article was written by Anne Eisenberg and appears on page E1.
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Comments: dqemail@aol.com (1998-12-27)