View full-text article in PMC Prev Sci. Author manuscript; available in PMC: 2011 Feb 24. Published in final edited form as: Prev Sci. 2010 Sep;11(3):239–251. doi: 10.1007/s11121-010-0169-2 Search in PMC Search in PubMed View in NLM Catalog Add to search Copyright and License information PMC Copyright notice Figure 1. Relations Modeled in Simulations Note: expit(x)=exp(x)1+exp(x) Note: ε1, …, εT−1, ε are independent Normally distributed random variables each with mean 0 and variance 1, and εY=ϕ(∏t=0T−2δt)X+∑s=1T−2ϕ(∏t=sT−2δt)εs+ϕεT−1+ε is a Normally distributed random variable with mean zero and variance: Var(εY)=ϕ2(∏t=0T−2δt)2+∑s=1T−2ϕ2(∏t=sT−2δt)2+ϕ2+1