Adult Radiotelemetry (1996-2004)
Travel Time Estimates
The Travel Time Estimates are based on the release date for each
radio-tagged fish and the first approach (A1**) and last record at top-of-the-ladder (LT) times at
each upstream detection site. Travel Time estimates for release to upstream site are calculated using the release time and the time of the first approach (A1**) record at the upstream site. Reach travel time is based on the last record at the top-of-ladder site (LT) at the first project and the first approach record (A1**) at the second project.
Arithmetic Mean Travel Time
(  reach travel time ) / number of unique fish detected at the detection sites
Harmonic Mean Travel Time
number of unique fish detected at the detection sites / ( (1/reach travel time) ) When dealing with travel times, we are primarily interested in the speed
with which fish travel from point A to point B. A good statistic for
describing a particular group's speed is the harmonic mean. A harmonic mean
is used when working with rates of speed, usually the number of days to
travel a set distance. A benefit to using the harmonic mean is that it is
more robust in the presence of outliers (i.e., a very fast or slow fish).
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