DERIVATIVES OF FLOWS IN A DOUBLY CONSTRAINED GRAVITY MODEL
研究了双重约束重力模型中流量如何随边际总量的微小变化而变动，提出了几种计算该线性函数矩阵的方法，并展示了其在敏感性和误差传播分析中的应用。
ABSTRACT For many practical applications it is important to know how the flows in a doubly constrained gravity model react to slight variations in the predetermined marginal totals. The first‐order approximation of these variations is a linear function on the set of feasible variations of marginal totals, i.e., the set of variations not violating the consistency constraint of the model. Several methods to find a matrix describing this linear function are developed and compared with former contributions to this issue. Finally, applicability of the methods to sensitivity and error propagation analysis is demonstrated.