allow some simulation parameters to be observed from exponential distribution (rather than using fixed val)
allow some simulation parameters to be observed from exponential distribution (rather than using fixed val)

smozaffari/WASP,smozaffari/WASP,smozaffari/WASP,bmvdgeijn/WASP,gmcvicker/WASP,bmvdgeijn/WASP,smozaffari/WASP,gmcvicker/WASP,bmvdgeijn/WASP,bmvdgeijn/WASP,smozaffari/WASP,gmcvicker/WASP,gmcvicker/WASP