数学中国www, madio,net 158 The UMAP Journal 29.2(2008) The multicomponent indices are problematic conceptually and method ologically; they are not useful to guide policy, in part because of the opacity of their component measures. " Primary health care is declared a failure without examining adequate evidence, apparently based on the authors ideological position ."These methodological issues are not only matters of technical and scien- consequences. Improved WHO Method In the WHO methods, the weights in the construction of the composite index are used without considering uncertainty in the values of the different nen Weuse agrey comprahensive evaluation mode? toimprove the WHOmethod to make the evaluation more credible Methodology e Suppose that ck, for are the raw data of the metrics k= l,.m in suntry i, for i=1, ..,n, giving the n x m matrix=(c).We suppose cR=(ci,,,, c), a best possible situation, as a reference and compare the value of metric k in country i to this ideal via s(k)=min, Ic-cal+ pmaxiIct lc+k-eu+pmax Ic where p E(0, 1)is a differentiation coefficient that we generally can take to be.5. Using,(k), we get the evaluation matrix E=5()\s for them mtrppose W=(wi,., Wm)is a weight-distribution vector for the m metrics, with w the weight of metric k and >wk= 1. Based on the dis- cussion above, we get the grey comprehensive evaluation model R=W·E=(n1,…,rn ' S NOTE: This method, not known under this name in the US. was introduced by Deng Julong in Tutorial of Gray Systean Theory [in Chinese](1982). It uses ideas of TL Saaty's analytic hierarchy process and is well well-known in China(googling"grey aystem"gets 64,100 hits, induding The Journal of Grey Systemt, edited by Deng). For a numerical example, see Sun, Yan and Zong Sun, The grey comprehensive evaluation model for safety of construction sites, 2007 International Conference on winless CommunicatIons, Networking and Mobile Camping, 5240-5243数学中国 www.madio.net