When intervals between surveys vary so greatly, and where questions are so limited, it is extremely difficult to identify trends, or draw comparisons.
Although the Agriculture Department surveys beekeeping operations every five years using criteria that address some of these issues, five years between surveys provides ample time for irreparable damage to occur before a problem can be recognized.
The period of time between surveys was 3 months.
Medians also tend to differ between surveys, possibly reflecting survey design differences.
Species-specific densities (abundance and biomass) showed significant differences between surveys, depth strata and their interaction in BsB.
Changes in reservoir geophysical attributes between surveys can be used to evaluate fluid types, phases, flow, and pressures as a function of time.
The polynomial SAREG geomagnetic field model for each annual field survey from 2005 till 2014 not only describes main field components but also the time variation between surveys.
A further limitation was loss to follow-up between surveys, since 68 and 63% of the original sample completed waves 2 and 3, respectively.
Perceptions of likelihood of another bioterrorism event increased between surveys, as would be expected; however, a tendency to believe that it would not happen locally persisted.
During the nine years between surveys, the length of fallow period decreased by 48%, from an average length of 12.1 in 2005 to 6.3 years in 2014.
Spatial congruence between "true" and "estimated" hotspots declined rapidly with increasing time interval between surveys, due primarily to increasing false negatives (i.e., missing "true" hotspots).
