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beast-dev / tracer

Posterior summarisation in Bayesian phylogenetics
https://beast.community/tracer
GNU Lesser General Public License v2.1
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bayesian skygrid caution #176

Closed gh1of1 closed 2 years ago

gh1of1 commented 2 years ago

Hi Walter,

I am a beginner of BEAST and came into an issue when processing data for the Beyasian skygrid plot. My dataset includes 170 sequences range from the 1980s till now. And actually this dataset was plotted using skyline model before. I tried to repeat with skygrid model. However, after I run the BEAST with new xml file generated from Beauti and trace it with Tracer, I found the skygrid reconstruction plot shows weird. The plot showed three parallel horizontal lines (95HPD and median) until the time of 2017. It should start to fluctuate from the time before 1980s I think. Could you please help on this issue? I tried to troubleshoot for a few days and re-run a lot times with different parameters, but came to nothing.

Many thanks!

WechatIMG743 WechatIMG744

gh1of1 commented 2 years ago

Solved. The point is to understand the meaning of "time at last transition point" under "Trees" in BEAUTi.