reat majority of transit planning applications. However, in certain applications it is not sufficient to know the total number of transfers at each transfer node, but it is necessary to assess the number of trips that transfer at a given node from one particular line (and direction) to another. This means that instead of just the total number of transfers at a given node, a line-to-line transfer matrix is needed. Ideally, such a transfer matrix could be computed for each transit node in the network. But this would amount to a huge quantity of data, in general requiring orders of magnitude more storage space than is needed for the standard assignment results. For the Winnipeg standard demonstration network, there are 57'333 possible line-to-line transfers, but only 4'272 transit line segments. Given this and the fact that the number of possible line-to-line transfers at a node is the square of the number of lines stopping at the node (which by the way is not restricted in EMME/2), it is clear that these transfer matrices are not provided as a standard result in EMME/2. However, in practice it is most always necessary to know the transfer matrices at only a few transfer nodes in the network (which ones, of course, depend on the particular issues that are to be studied in the application).
In the past, two types of simplistic approaches to solve this problem have been used in practice by some EMME/2 users.
In the first type of methods, the network topology is changed by splitting the transfer node into different nodes which are interconnected with a ``matrix'' of walk links. The big drawback of this approach is that this network transformation changes the route choice and, thus, the assignment results, since the lines at the transfer node can no longer be combined to reduce waiting time.
In the second type of approach, the network is left unchanged, but instead of a simple assignment, a series of assignments is carried out, mimi
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