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. 2022 Aug 16;130(8):087006. doi: 10.1289/EHP10287

Table 2.

List of model equations used for West Nile virus forecasting in South Dakota.

Model Equation
Base logit(pi,t)=c0i+cyc(w)
Mosq logit(pi,t)=c0i+c1mi,t+cyc(w)
Env logit(pi,t)=c0i+k=12l=0Lsk(l)ui,tl
EnvAnom logit(pi,t)=c0i+cyc(w)+k=12l=0Lsk(l)ai,tl
EnvSv logit(pi,t)=c0i+k=12l=0Lsk(l,w)ui,tl
EnvSvAnom logit(pi,t)=c0i+cyc(w)+k=12l=0Lsk(l,w)ai,tl
Comb logit(pi,t)=c0i+c1mi,t+k=12l=0Lsk(l)ui,tl
CombAnom logit(pi,t)=c0i+c1mi,t+cyc(w)+k=12l=0Lsk(l)ai,tl
CombSv logit(pi,t)=c0i+c1mi,t+k=12l=0Lsk(l,w)ui,tl
CombSvAnom logit(pi,t)=c0i+c1mi,t+cyc(w)+k=12l=0Lsk(l,w)ai,tl

Note: pi,t is the probability of one or more WNV cases in county i at time t; coi is a county-level fixed effect; mi,t is the mosquito infection growth rate (MIGR) in county i at time t; c1 is the parameter for MIGR; cyc(w) is a cyclical seasonal function; k indexes two meteorological variables; l indexes daily lags up to L=120 days in the past; sk(l) is a thin-plate spline function of lag days; sk(l,w) is a thin-plate spline function of lag days and week of the year; ui,tl is an untransformed meteorological variable for county i at time tl and ai,tl is an anomalized meteorological variable for county i at time tl. Base, baseline; Comb, combined; CombAnom, combined with anomalies; CombSv, combined with seasonally varying distributed lags; CombSvAnom, combined with anomalies and seasonally varying distributed lags; Ens2, two model ensemble; Ens3, three model ensemble; Ens4, four model ensemble; Env, environmental; EnvAnom, environmental with anomalies; EnvSv, environmental with seasonally varying distributed lags; EnvSvAnom, environmental with anomalies and seasonally varying distributed lags; Mosq, mosquito.