Abstract: A method for enabling a user to interactively create and modify a model of an investment strategy to be applied to data pertaining to a set of possible investment entities. A graphical representation of a sequence of statements which describe data manipulations corresponding to the investment strategy is provided; the result of the sequence of statements, when applied to the data, is a selection of a subset of entities from the set of possible entities. The user is enabled to interactively enter and manipulate the statements and the sequence of statements via the graphical interface to alter the investment strategy. The user may "run" the strategy via the graphical interface, using the data to derive the subset of entities.

Abstract: In a digital communications system comprising a plurality of modules plugged into slots, the backplane provides a private five-conductor data bus for each module slot so that data from the modules are transmitted over separate busses. Each of the data busses is split into separately driven branches extending to the right and to the left of its corresponding module, so that the drivers are located at the ends of the branches rather than connected to an intermediate point on a bus. Pairs of slots are connected through the backplane so that, instead of having one module in each slot driving a five conductor data bus, the system can alternatively have a double-bandwidth module in every other slot driving a ten-conductor data bus made up of two five-conductor busses. Clock and synchronization signals provided by control modules are conducted to device modules over separate conductors on the backplane.