Patent ID: 7412508

Claim:
Device for calculating an estimate of a number of downloadings of a data item from a first computer by a first group of user computers which are configured for not allowing execution of a browser script and the cache memories of which comprise the data item, the device comprising a processor being configured for calculating the estimate according to the following relation: A*D/B, where A is a number of downloadings from a second plurality of user computers allowing execution of a browser script and in which the cache memories comprise the data item, B is a number of downloadings from a third plurality of user computers allowing execution of a browser script and in which the cache memories are one of absent, out of order, and do not comprise the data item, and D is a number of downloadings from a fourth plurality of user computers, not allowing execution of a browser script and in which the cache memories are one of absent, out of order, and do not comprise the data item; and indicating the estimate.