Mean first passage time (MFPT)

• MFPT calculation method for random walkers in inhomogeneous media is proposed. • Convex network primitives optimized with an extension of particle swarm optimizer. • MFPT calculated in a 'hop-wise' approach weighed by probability distributions. • Methods verified with real cyclone track dataset over the North Atlantic Ocean. • Results show over three times increase in accuracy with proposed model. a b s t r a c t Knowing the expected arrival time at a particular state, also known as the mean first passage time (MFPT), often plays an important role for a large class of random walkers in their respective state-spaces. Contrasting to ideal conditions required by recent advancements on MFPT estimations, many naturally occurring random walkers encounter inhomogene-ity of transport characteristics in the networks they walk on. This paper presents a heuris-tic method to divide an inhomogeneous network into homogeneous network primitives (NPs) optimized using particle swarm optimizer, and to use a 'hop-wise' MFPT calculation method. This methodology's potential is demonstrated through simulated random walks and with a case study using the dataset of past cyclone tracks over the North Atlantic Ocean. Parallel processing was used to increase calculation efficiency. The predictions using the proposed method are compared to real data averages and predictions assuming homogeneous transport properties. The results show that breaking the problem into NPs reduces the average error from 18.8% to 5.4% with respect to the homogeneous network assumption .