The reference machine's results are called the baseline results. If we divide the results of the system under examination by the baseline results, we obtain a performance index . Obviously, the performance index for the reference machine is 1.0. An index has no units, it is just a relative measurement. 1.6 Resolution and precision Resolution and precision both measure the information provided by a data point, but should not be confused.
Precision is a measure of the total variability in the results for any given benchmark.
Computers are deterministic systems and should always provide the same, identical benchmark results if running under identical conditions. Note that whereas resolution is system dependent, precision is a characteristic of each benchmark. Ideally, a well-designed benchmark will have a precision smaller than or equal to the resolution of the system being tested. It is very important to iden tify the sources of noise for any particular benchmark, since this provides an indication of possibly erroneous results. Whetstone is an example of a synthetic benchmark.