Analysis of the original, numerical components of diverse geomorphic and tectonic process rates indicates that process rate is not independent of measured time interval. This implies that direct comparison of geologic process rates measured over variable time intervals may not be valid and that conclusions based on those comparisons regarding changes in rates through geologic time may be misleading in some cases. Calculation of statistically derived scaling functions is one approach that can be used to account for this measurement-interval bias and to improve comparisons of geologic-process rate data. When this approach is used, a 104 or 105 yr variation in the measured time interval accounts for approximately one order of magnitude change in the measured process rate. The magnitude of the correction can substantially affect conclusions of studies that compare uncorrected process rates calculated from variable time intervals.