灰色模型GM(1,1)在出生缺陷预测中的应用研究

Application of the gray model GM (1,1) in predicting birth defects

目的探讨灰色模型GM(1,1)在预测不同水平出生缺陷发生率中的应用问题及数据波动性对预测效果的影响。方法利用2009年10月至2016年9月西安市出生缺陷监测数据,构建总出生缺陷及前5种缺陷的月、季度、年共3个层次出生缺陷发生率的GM(1,1)灰色模型,比较不同层次预测模型的拟合精度。结果总出生缺陷年度预测时,平均相对误差为4.6%,均方差比为0.259,提示其预测效果较好;按季度预测时效果勉强合格,平均相对误差为10.2%;按月进行预测时,效果较差,平均相对误差为17.5%。西安市前5种出生缺陷(先天性心脏病、唇腭裂、神经管畸形、多指、先天性脑积水)灰色模型预测结果都随着预测时间单位的变大,拟合精度逐渐提高,年预测模型拟合精度最好。结论灰色模型的预测效果可能与数据波动性有关,对出生缺陷发生率进行预测时以年度为单位的结果可能较适宜。

Objective To investigate the application of gray model GM(1,1)in predicting the incidence of birth defects at different levels and the effect of data volatility on the prediction outcome.Methods Based on the monitoring data of birth defects in Xi'an from October 2009 to September 2016,the GM(1,1)was used to predict the overall incidence of birth defects and incidence of five main birth defects at three levels(month,quarter,and year).We compared the fitting accuracy of different level prediction models.Results The average relative error for yearly prediction of overall birth defect was 4.6%,and the mean square deviation was 0.259,which might suggest better prediction.Quarterly forecasting results were almost qualified and the average relative error was 10.2%.Monthly prediction was poor with an average relative error of 17.5%.With the extension of the forecast period,the grey model prediction results of the top five birth defects(congenital heart disease,cleft lip and palate,neural tube defects,multiple fingers,and congenital hydrocephalus)in Xi'an all increased,and the fitting accuracy gradually improved.The gray scale of the year was the best.Conclusion The prediction results of the gray model may be related to the volatility of the data.It may be suitable for predicting the incidence of birth defects by the year.