Origin-Destination-Based Travel Time Reliability under Different Rainfall Intensities: An Investigation Using Open-Source Data

Algorithm 1

EM algorithm for estimating LMM.

	Step 1:
	Initialize K-value and LMM.
	Step 2 (E step):
	Calculate the probability of each travel time (sample size N) belonging to each lognormal distribution according to (i).
(i)	.
	Step 3 (M step):
	Update all parameters in LMM according to (ii)–(iv).
(ii)	.
(iii)	.
(iv)	.
	Step 4:
	Repeat until convergence.