[ewilliams]

Yes, the beta is often a good refinement for what might otherwise be modeled as a triangular distribution. Its suitability as a refinement of the triangular is based largely on the fact that both distributions are bounded on both ends. A beta distribution can have much thinner tails, depending on how its shape parameters (often denoted alpha-1 and alpha-2) are chosen. The beta, like the triangular, can be positively skewed, negatively skewed, or symmetric. If the two alpha parameters are equal, it will be symmetric. If alpha-1 > alpha-2, the distribution will be left-skewed, and vice versa.