H7N9 not only endanger human health but also hit stock marketing

Jiang, Yan; Zhang, Yi; Ma, Chunna; Wang, Quanyi; Xu, Chao; Donovan, Connor; Ali, Gholam; Xu, Tan; Sun, Wenjie

cb(x i ; β x ) is the "cross-basis" function of x i with the regression coefficient of β x and is used to model the effect of the daily reported case number in the space of reported number and lags. Within each space, natural cubic spline is used to get a flexible fit. Then, in order to get a better fit in the range of the reported number, the knots were placed at equally spaced percentile of the asymptotically Poisson distributed values of reported number. For the dimension of the lags, suggested by previous studies, we put the knots at equal intervals in the logarithmic scale of lags to allow more flexibility in the first part of the distributed lag curve, where more variability is expected [13] . The maximum lag L was set to 2 days.