OrnsteinUhlenbeckProcess

OrnsteinUhlenbeckProcess[μ,σ,θ] represents a stationary Ornstein–Uhlenbeck process with long-term mean μ, volatility σ, and mean reversion speed θ. 

OrnsteinUhlenbeckProcess[μ,σ,θ,x0] represents an Ornstein–Uhlenbeck process with initial condition x0.

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