On the centenary of the German hog cycle: new findings
研究了德国猪饲料价格比的周期性行为，发现一个显著的四周期且波动性在增加，对农业经济学家和猪周期研究者有参考价值。
Perhaps the earliest systematic study that investigated the cyclical nature of hog prices was that conducted by Gerlich in 1911 using German data from the late nineteenth and early twentieth century. Using data from the late twentieth and early twenty-first century, we model the behaviour of the German hog-feed price ratio. A dynamic unobservable time series model which incorporates both a stochastic trend and a stochastic cycle is developed and applied to these data. We find a significant four-year cycle and provide evidence that it is becoming more volatile.