Question

Problem 4 Figure 1 presents a simple three-zone system, the link travel times in minutes (wj) for this system, and the observed zonal productions and attractions. Assuming a doubly constrained gravity model with friction factor F, (a) Compute P-A flows (production-attraction matrix) for this system for values of b of 1.0, and 1.5 (b) Table 1 below presents the observed P-A flows for this system. Which value of b provides the "best-fit" to the observed data? Note: Best-fit should be measured by R2, the coefficient of determination. Show the steps of your solution to the problem. Preferably, this problem should be solved using spreadsheet software such as MS Excel. Table 1:Observed P-A flows for three-zone system rom 130 80 30 15 80 40 P-150 Ai-250 P 200 A2- 50 P-100 Aj-150 wir-w22- w33-2min Figure 1: Tree-Zone System

Answer 1

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2녀6.01 2 su.oa