A response from him would be very interesting. Metric conversion would gain greater acceptance among the population, especially those who would profit from it, if it can be proved that not being metric is damaging both the stability of the American economy and the education of American citizens. Especially if it profits foreign competitors at the expense of Americans.
But how will we know the true effects unless a study is made of the situation? Jerry ________________________________ From: Robert H. Bushnell <[email protected]> To: U.S. Metric Association <[email protected]> Cc: [email protected] Sent: Friday, February 13, 2009 2:42:09 PM Subject: [USMA:42993] Learning and Scientific Reasoning 2009 February 13 Lei Bao, Your paper, "Learning and Scientific Reasoning" Science Vol 323 30 January 2009, reports differences in Chinese and USA student's scores on Mechanics and Electricity and Magnetism. The students background in measurement units is not reported. Students in the USA do not have a background in metric units whereas students in China have lived their whole lives with metric (SI) units. In the USA the teaching of science and engineering is hindered by the need to spend class time on units. In the USA energy is given in calories, watt hours, BTU, some other units and even joules. This makes it necessary to spend class time on units with the result that less time is spent on physics. Do you have any data on how this affects the scores you report in the paper? Do you have data from Germany or France where SI is used in the whole of student's lives. Do you have any data on how long it takes a student to learn that all energy can be expressed in joules and that all science subjects use the same background for energy? Does this make physics easier to learn? How much of the difference in the position of the peaks in your paper is caused by the different life-time exposure to units? It is estimated (metricationmatters.com) that the cost for the USA to continue using inch-pound units is some $1000 billion each year. Possibly half of this cost is in schools. This seems to say that units have a big effect and so might contribute to the separation of the curves you report. Please tell me what you know of the effect that inch-pound units have on your results. Thanks, Robert H. Bushnell PhD PE
