A Grey Seasonal Index Model for Forecasting Groundwater Depth of Ningxia Plain

<table class="table-group" id="tab4"><tr><td><table class="table"><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr class="thead"><td class="align_left">Year</td><td class="align_center">Actual value</td><td class="align_center">Fitting value</td></tr><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr><td class="align_left">2014</td><td class="align_center">26.68</td><td class="align_center">26.68</td></tr><tr><td class="align_left">2015</td><td class="align_center">25.83</td><td class="align_center">25.81</td></tr><tr><td class="align_left">2016</td><td class="align_center">25.71</td><td class="align_center">25.70</td></tr><tr><td class="align_left">2017</td><td class="align_center">28.02</td><td class="align_center">27.70</td></tr><tr><td class="align_left">2018</td><td class="align_center">30.66</td><td class="align_center">30.74</td></tr><tr><td class="align_left">MAPE</td><td class="align_center"> </td><td class="align_center">0.38</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>The annual fitting value of Yinchuan Plain groundwater depth (unit: m).</div>

Discrete Dynamics in Nature and Society

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Table 4

Table 4: A Grey Seasonal Index Model for Forecasting Groundwater Depth of Ningxia Plain 