Abstract:
Weintroduce two simple methods for the statistical comparison of the temporal pattern
of life-cycle events between two populations. The methods are based on a translation of stagefrequency
data into individual Ôtimes in stageÕ. For example, if the stage-k individuals in a set of samples
consist of three individuals counted at time t1 and two counted at time t₂, the observed times in stage
k would be (t₁, t₁, t₁, t₂, t₂). Times in stage then can be compared between two populations by
performing stage-speciÞc t-tests or by testing for equality of regression lines of time versus stage
between the two populations. Simulations show that our methods perform at close to the nominal level,
have good power against a range of alternatives, and have much better operating characteristics than
a widely-used phenology model from the literature.
