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基于ARIMA的猪瘟发病率预测模型的建立 总被引：1，自引：0，他引：1
为探讨应用自回归-移动平均ARIMA(P,d,q)模型预测猪瘟发病率的可行性,本研究对1999年1月～2004年12月A、B、C 3个地区的逐月猪瘟发病率进行ARIMA模型的拟合,用2005年1月～2005年12月的猪瘟发病率进行模型预测效果的验证.结果显示ARIMA(0,1,2)模型计算出的预测值与实际值拟合较好,可用于对未来的猪瘟发病率进行预测,为猪瘟的防控工作提供可靠的参考依据. 相似文献
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依据粮农组织数据库中给出的1961—2005年的中国牛肉产量数据为基础,分别通过差分把非平稳时间序列转化为平稳时间序列。建立了ARIMA(1,2,1)模型对中国牛肉产量进行预测。根据新华社对2006年中国牛肉产量的报道和德国莱茵农业协会对2007年中国牛肉产量的估计结果来看,ARIMA模型的预测误差只有1%左右,模型预测良好。 相似文献
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油料在国民经济中占据着重要地位,河北省大名县作为油料产量大县,近20年油料总产量在河北省各县中一直位居首位,但在多方面因素综合影响下近十年大名县油料产量呈下降趋势,产业发展受到一定程度影响.文章基于大名县1994～2019年油料产量数据,分别运用SPSS软件和Eviews软件建立GM(1,1)模型和ARIMA模型,进行1995～2022年油料产量的预测仿真,预测结果表明ARIMA模型比GM模型具有更高的预测精度和拟合效果.由预测结果分析了大名县油料产量和面积发生变动的原因,并提出了加快油料生产基地的建设、加快推动产供销一体化、提高油料生产组织化程度、引入新品种新技术、提高油料生产机械化水平等促进大名县油料发展的建议. 相似文献
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为了比较新疆农七师荷斯坦牛不同模型泌乳曲线拟合效果,以该师奶牛场2004年3月~2009年10月间656头中国荷斯坦牛9 426个完整泌乳记录为基础,应用Wood不完全伽玛函数模型、Nelder逆多项式模型、Wilmink模型3个数学模型,对第1胎、第2胎、第3胎和第4胎及所有胎次的泌乳曲线进行了拟合。结果显示,利用Nelder逆多项式模型拟合泌乳曲线,其拟合度(R2)为0.1271～0.9431;利用Wilmink模型拟合泌乳曲线,其拟合度(R2)为0.8944～0.9471;利用Wood模型拟合泌乳曲线,其拟合度(R2)为0.8948～0.9475。结果表明,农七师荷斯坦牛泌乳曲线最佳拟合模型为Wood模型。 相似文献
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利用时间序列模型预测未来两年新疆乌鲁木齐市羊布鲁氏菌病的流行趋势,为制定合适的防控措施提供依据。针对新疆乌鲁木齐市2012～2017年羊布鲁氏菌病监测数据,利用Holt双参数指数平滑法建立时间序列模型,预测未来两年羊布鲁氏菌病的发病趋势。结果表明:Holt双参数指数平滑法能够较好地拟合出乌鲁木齐市羊布鲁氏菌病检测阳性率的变化趋势,平均绝对百分比误差(MAPE)为0.013%,预测出2018～2019年羊布鲁氏菌病的检测阳性率分别为1.02%(95%CI:0.25%～4.18%)和1.51%(95%CI:0.04%～54.94%)。Holt双参数指数平滑法模型可用于短期预测羊布鲁氏菌病检测阳性率的变化趋势。 相似文献
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对气象数据和猪蓝耳病发病率进行相关性分析,结合动物流行病学理论确定影响猪蓝耳病发病的关键气象因素.利用Matlab软件进行BP(Back-propagation)神经网络预测模型构建,计算预测值与实际发病率的误差绝对值和决定系数R2对所建预测模型进行检验.结果表明,将13种气象因素作为预测研究的关键气象因子,BP神经网络模型其决定系数R2=0.821,证实预测效果较好.初步构建出猪蓝耳病发病的神经网络预测模型,探索性地将BP神经网络理论在动物疫病预测研究领域中运用,为进一步展开动物疫病预测的研究提供理论参考. 相似文献
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Predicting campylobacteriosis cases is a matter of considerable concern in New Zealand, after the number of the notified cases was the highest among the developed countries in 2006. Thus, there is a need to develop a model or a tool to predict accurately the number of campylobacteriosis cases as the Microbial Risk Assessment Model used to predict the number of campylobacteriosis cases failed to predict accurately the number of actual cases. We explore the appropriateness of classical time series modelling approaches for predicting campylobacteriosis. Finding the most appropriate time series model for New Zealand data has additional practical considerations given a possible structural change, that is, a specific and sudden change in response to the implemented interventions. A univariate methodological approach was used to predict monthly disease cases using New Zealand surveillance data of campylobacteriosis incidence from 1998 to 2009. The data from the years 1998 to 2008 were used to model the time series with the year 2009 held out of the data set for model validation. The best two models were then fitted to the full 1998–2009 data and used to predict for each month of 2010. The Holt‐Winters (multiplicative) and ARIMA (additive) intervention models were considered the best models for predicting campylobacteriosis in New Zealand. It was noticed that the prediction by an additive ARIMA with intervention was slightly better than the prediction by a Holt‐Winter multiplicative method for the annual total in year 2010, the former predicting only 23 cases less than the actual reported cases. It is confirmed that classical time series techniques such as ARIMA with intervention and Holt‐Winters can provide a good prediction performance for campylobacteriosis risk in New Zealand. The results reported by this study are useful to the New Zealand Health and Safety Authority's efforts in addressing the problem of the campylobacteriosis epidemic. 相似文献
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L. Yang Z.‐W. Bi Z.‐Q. Kou X.‐J. Li M. Zhang M. Wang L.‐Y. Zhang Z.‐T. Zhao 《Zoonoses and public health》2015,62(3):228-235
Human brucellosis is a re‐emerging bacterial anthropozoonotic disease, which remains a public health concern in China with the growing number of cases and more widespread natural foci. The purpose of this study was to short‐term forecast the incidence of human brucellosis with a prediction model. We collected the annual and monthly laboratory data of confirmed cases from January 2004 to December 2013 in Shandong Diseases Reporting Information System (SDRIS). Autoregressive integrated moving average (ARIMA) model was fitted based on the monthly human brucellosis incidence from 2004 to 2013. Finally, monthly brucellosis incidences in 2014 were short‐term forecasted by the obtained model. The incidence of brucellosis was increasing from 2004 to 2013. For the ARIMA (0, 2, 1) model, the white noise diagnostic check (x2 = 5.58 P = 0.35) for residuals obtained was revealed by the optimum goodness‐of‐fit test. The monthly incidences that fitted by ARIMA (0, 2, 1) model were closely consistent with the real incidence from 2004 to 2013. And forecasting incidences from January 2014 to December 2014 were, respectively, 0.101, 0.118, 0.143, 0.166, 0.160, 0.172, 0.169, 0.133, 0.122, 0.105, 0.103 and 0.079 per100 000 population, with standard error 0.011–0.019 and mean absolute percentage error (MAPE) of 58.79%. 相似文献
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鸡蛋是我国居民日常生活中最常见的蛋白质食品,在众多农产品中鸡蛋价格波动对物价水平以及居民消费价格指数的影响尤为显著,提前分析预测鸡蛋价格对调控鸡蛋市场供需关系、促进禽蛋产业健康发展有重要意义。研究采用ARIMA时间序列分析模型,以全国500个县集贸市场2013年1月1日~2019年7月31日每周的鸡蛋平均价格为分析与建模基础,并对后期8周的鸡蛋价格进行了预测。 相似文献
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OBJECTIVE: To calculate the monthly incidence of gastric dilatation-volvulus (GDV) in a population of military working dogs during a 5-year period and determine whether there was an association with synoptic climatologic indices. SAMPLE POPULATION: Medical records of all military working dogs housed at Lackland Air Force Base,Tex, from Jan 1, 1993 to Dec 31, 1997. PROCEDURE: Confirmed cases of GDV were identified from evaluation of medical records and used to calculate incidence of GDV. Factor analysis of local climatologic data was used to classify each day into 1 of 8 meteorologically homogeneous types of days for this location. Occurrence of GDV was compared with frequency of occurrence of synoptic climatologic days. RESULTS: 48 cases of GDV were identified from January 1993 through December 1997 Mean monthly incidence was 2.5 cases/1,000 dogs at risk (range, 0 to 18.5 cases/1,000 dogs; median, 2.5 cases/1,000 dogs). A seasonal increase in incidence of GDV was detected, because half of the episodes were during November, December, and January. An association with a specific synoptic climatologic day was not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Seasonal fluctuations in incidence of GDV may be associated with external factors that precipitate physiologic changes resulting in GDV. Although a specific cause-effect relationship was not documented, clinicians must be alert for the potential of seasonal variation in incidence of GDV and accordingly heighten their index of suspicion for the condition, particularly in populations of dogs that are predisposed to development of GDV. 相似文献
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应用ARIMA模型（差分自回归移动平均模型）对圈养亚成体大熊猫24h的取食行为节律时间序列进行分析和预测。根据序列图判断时序数据的平稳性,结合自相关及偏自相关函数确定分析模型为ARIMA（p,d,q）（P,D,Q）~8模式。基于Expert Modeler模块和AIC信息评判原则筛选ARIMA模型的最佳阶数组合为ARIMA（0,0,1）（1,1,0）~8。模型参数估计均通过显著性检验,预测值的置信区间包括所有实际观测数值。预测值残差的自相关与偏自相关函数值均在置信区间内,残差为白噪声,模型的检验结果比较理想和有效。 相似文献
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时间序列分析在蚕种销售中的应用研究 总被引：2，自引：0，他引：2
基于探讨广西蚕区家蚕普通种销售市场发展规律,为广西蚕业生产的宏观管理提供决策依据的目的,采用时间序列季节性乘积模型对家蚕普通种销售市场的发展变化规律进行了研究。依据广西蚕区2004-2006年36个月份的每月蚕种销售数量,运用社会科学统计软件包(SPSS)软件进行时间序列分析,建立了广西蚕区家蚕普通种市场销售规律的统计预测模型,即季节性乘积求和自回归滑动平均模型:AR IMA(0,1,1)×(0,1,1)12,并通过白噪声检验。利用该模型对广西蚕区2006-2007年家蚕普通种每月销售量进行了预测,得到较为准确的预测结果。 相似文献
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AIM: To estimate genetic and crossbreeding parameters for the incidence of recorded clinical lameness in New Zealand dairy cattle. METHODS: Herd records from 76,357 cows, collected during the 2005/06 to 2008/09 milking seasons from 155 herds in the Livestock Improvement Corporation young sire progeny test scheme, were used to estimate genetic parameters and breed effects for incidence of recorded clinical lameness in HolsteinFriesian, Jersey and crossbred dairy cattle. Recorded clinical lameness was coded “1” for cows that presented at least one event of clinical lameness at any day during the season and “0” for unaffected cows. Genetic parameters were estimated using an animal model across breeds considering all and then only first lactation records. Heritability and repeatability of recorded clinical lameness were calculated from the variance component estimates both with and without logit transformation. RESULTS: The mean incidence of recorded clinical lameness per herd was 6.3 (min 2, max 34)%. The incidence of recorded clinical lameness in Holstein Friesian cows (mean 6.8, SE 0.24%) was higher than the incidence of recorded clinical lameness in crossbred (mean 6.1, SE 0.19%) and Jersey cows (mean 6.0, SE 0.28%) (p=0.0002). There was no difference in incidence between crossbred and Jersey cows (p=0.96). Estimates of the heritability of recorded clinical lameness as an untransformed trait were 0.053 (SE 0.014) for first lactation records and 0.016 (SE 0.003) for all lactation records. As a transformed (logit) trait heritabilities were 0.067 (SE 0.024) and 0.044 (SE 0.016) for first and all lactation records, respectively. The repeatability estimates of recorded clinical lameness were 0.071 (SE 0.005) and 0.107 (SE 0.011) for untransformed and logit transformed lactation records, respectively. Sire estimated breeding values for recorded clinical lameness showed the lowest values in Jersey sires, and ranged between -5 and 8%. CONCLUSIONS: Despite the low heritability of recorded clinical lameness, this study provided evidence that there is significant exploitable animal genetic variation. Selection of specific sires across and within breeds could be an option for increasing genetic resistance to lameness in New Zealand dairy cattle. 相似文献