Two-Stage Method Based on Local Polynomial Fitting for a Linear Heteroscedastic Regression Model and Its Application in Economics

<table>The fitting plot and its residual plot when <svg height="12.4375" id="M168" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 48.512501 12.4375" width="48.512501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> and <svg height="15.2875" id="M169" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 37.787498 15.2875" width="37.787498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,0,0,-.017,.062,10.863)"><path d="M570 304q0 -108 -87 -199q-40 -42 -94.5 -74t-105.5 -43q-41 0 -65 11l-29 -141q-9 -45 -1.5 -58t45.5 -16l26 -2l-5 -29l-241 -10l4 26q51 10 67.5 24t26.5 60l113 520q-54 -20 -89 -41l-7 26q38 28 105 53l11 49q20 25 77 58l8 -7l-17 -77q39 14 102 14q82 0 119 -36
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</svg>: (a) fitting plot, (b) residual plot.</table>

Discrete Dynamics in Nature and Society

fig2

Figure 2

Figure 2: Two-Stage Method Based on Local Polynomial Fitting for a Linear Heteroscedastic Regression Model and Its Application in Economics 