Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
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A lock (
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connected to the .gov website. Share sensitive
information only on official, secure websites.
For each origin site, the black vector indicates the null hypothesis direction (isotropic radial propagation), while the red one indicates the estimated grand-mean direction and the yellow circular sector depicts the variability (95% confidence interval) between individuals. Data indicate a systematic tendency to drift toward frontal areas.
