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Journal of Computers - Academy Publisher

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JOURNAL OF COMPUTERS, VOL. 6, NO. 9, SEPTEMBER 2011 1829<br />

As can be seen from the above analysis, the main<br />

factors that influence China’s provincial manufacturing<br />

agglomeration include Market demand, Transportation,<br />

Industrial foundation, Supporting services and Financial<br />

income. Industrial foundation and Supporting services<br />

have positive impact on manufacturing agglomeration.<br />

Their elasticities are 1.3435 and 1.3270. While Financial<br />

income has a negative impact on manufacturing<br />

agglomeration with its elasticity -0.3536. Due to the fault<br />

<strong>of</strong> OLS method dealing with spatial autocorrelation, we<br />

intend to use spatial econometric models to analyze the<br />

influencing factors <strong>of</strong> manufacturing agglomeration. The<br />

new model is the one in estimation 2 <strong>of</strong> table 3:<br />

ln LQ = β0<br />

+ β1<br />

ln demand + β2<br />

ln road + β3<br />

ln<br />

+ β4<br />

ln service + β5<br />

ln fisc − income + ε<br />

We need to verify the existence <strong>of</strong> spatial<br />

autocorrelation before peforming spatial econometric<br />

analysis. The result <strong>of</strong> spatial dependence test is shown in<br />

table 4.<br />

Table 4: Spatial dependence test<br />

Spatial dependence MI/DF Statistics p value<br />

Moran’s I (Error) 0.1047 1.9679 0.0489<br />

LMLAG 1 0.2102 0.6465<br />

R-LMLAG 1 0.4540 0.5003<br />

LMERR 1 0.0931 0.7602<br />

R-LMERR 1 0.3370 0.5615<br />

LM-SARMA 2 0.5472 0.7606<br />

As is shown in table 4, LMERR, LMLAG, R-LMERR<br />

and R-LMLAG do not pass the test at significance level<br />

<strong>of</strong> 5%. And SEM is better comparing the value <strong>of</strong> LogL,<br />

industry AIC, SC and LR <strong>of</strong> SLM and SEM. The result <strong>of</strong><br />

estimation <strong>of</strong> SLM and SEM ( 8)<br />

is displayed in table 5.<br />

Table 5: SLM and SEM estimation <strong>of</strong> the factors <strong>of</strong> manufacturing agglomeration (2006-2008)<br />

SLM SEM<br />

Variables<br />

β<br />

Standard<br />

deviation<br />

t value p value β<br />

Standard<br />

deviation<br />

t value p value<br />

C 1.6128 0.5600 2.8797 0.0039 1.5984 0.5300 3.0154 0.0025<br />

lndemand 0.7757 0.1192 6.5054 0.0000 0.8018 0.0975 8.2223 0.0000<br />

lnroad 0.0742 0.0573 1.2952 0.1952 0.0851 0.0437 1.9457 0.0516<br />

lnindustry 1.3642 0.2306 5.9145 0.0000 1.3741 0.2224 6.1785 0.0000<br />

lnservice 1.3462 0.5464 2.4635 0.0137 1.3585 0.5442 2.4960 0.0125<br />

lnfisc-income 0.3370 0.2200 1.5319 0.1255 0.3516 0.2199 1.5985 0.1099<br />

ρ/λ 0.0621 0.1208 0.5146 0.6067 0.3324 0.1275 2.6064 0.0074<br />

Statistical test DF Statistics p value DF Statistics p value<br />

R 2 0.9296 0.9495<br />

LogL 4.8505 4.8034<br />

AIC 4.2989 2.3930<br />

SC 14.1073 10.8002<br />

LR 1 0.2285 0.6325 1 0.1344 0.7138<br />

As is shown in table 5, the coefficients <strong>of</strong> all variables<br />

are positive. It indicate that this estimation is more<br />

consistent with theoretical analysis. Industrial foundation<br />

and Supporting services have positive impact on<br />

manufacturing agglomeration. Their elasticities are<br />

1.3642 and 1.3462 in SLM, 1.3741 and 1.3585 in SEM.<br />

B. Prediction <strong>of</strong> Location Quotient <strong>of</strong> China’s Provincial<br />

Manufacturing<br />

BP neural network is error back propagation neural<br />

network and feedforward network. It is widely used in<br />

function approximation, pattern recognition and data<br />

compression. In this article, we will predict the 2009’s<br />

Location Quotient <strong>of</strong> China’s Provincial Manufacturing<br />

using Neural Network Toolbox in Matlab (2006, 2007<br />

and 2008’s location quotient are references for<br />

comparison). The Matlab program <strong>of</strong> prediction is as<br />

follows (take Beijing for example):<br />

clc<br />

close all<br />

clear all<br />

p0=[2.4289 2.1880 2.0585 1.6110 1.3667 1.4216<br />

1.4169 1.3470 1.2994 1.3316];<br />

day=1999:2008;<br />

plot(day, p0,'b+')<br />

© 2011 ACADEMY PUBLISHER<br />

hold on<br />

plot(day, p0, 'r-.')<br />

p1=(p0-min(p0))./(max(p0)-min(p0));<br />

for i=1:5;<br />

p(:,i)=p1(i:i+2);<br />

t(:,i)=p1(i+3);<br />

end<br />

p;<br />

t;<br />

for i=1:5;<br />

testp(:,i)=p1(i+1:i+3);<br />

testt(:,i)=p1(i+4);<br />

end<br />

net=newff(minmax(p),[20,1],{'logsig','purelin'},'trainl<br />

m');<br />

net.trainParam.lr=0.8;<br />

net.trainParam.epochs = 500;<br />

net.trainParam.goal = 0.001;<br />

net=train(net,p,t);<br />

y=sim(net,testp);<br />

E=testt-y;

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