Jon Lefcheck
I’m currently the Tennenbaum Coordinating Scientist for the Smithsonian MarineGEO Network. I was formerly a post-doctoral researcher at Bigelow Laboratory for Ocean Sciences in East Boothbay, ME, and at the Virginia Institute of Marine Science in Gloucester Point, VA. I received my Ph.D. in Marine Science from the College of William & Mary in 2015.
My interests span from community and applied ecology, with an emphasis on seagrass ecosystems, to biodiversity science and conservation to ecological statistics.
My research is broadly focused on understanding the causes and consequences of biological diversity, especially with respect to human well-being. To help with this goal, I develop new statistical methods and approaches, principally structural equation modeling (SEM). I write and maintain an R package to conduct SEM and teach international courses on the applications of this method. You can read more about SEM in all its forms in my online book.
My current work involves implementing long-term monitoring and coordinated experiments across the MarineGEO network. The purpose is to catalogue the variety of life in earth’s coastal zones, and also to understand what biodiversity–and its loss–means for these ecosystems. Through MarineGEO, I am also ushering in the next era of SeagrassNet and coordinating mapping, monitoring, and synthesis of seagrasses worldwide.
My prior post-doctoral work involved understanding the patterns and drivers of submerged aquatic vegetation in the Chesapeake Bay over the past 30 years, and the factors that drive herbivory on Caribbean coral reefs. My Ph.D. research focused on the application of organismal ‘functional traits’ to both experiments and observational surveys to demonstrate how knowing what an organisms does–rather than what it is called–may help us better describe and predict the consequences of changing biodiversity.
I started the blog sample(ECOLOGY) to share some of the thoughts, explorations, and R code that I stash away on a daily basis. Hopefully someone out there will find some use for it as well. (Even though I haven’t added a post in years!)
Also, follow me on Twitter!
Follow @jslefche
Ciao from a Mediterranean time series station in Italy!
Nice to see a fellow blogger, ecologist and R-user!
Dear Jon,
Where is your latest updated code/function of the rsquared.lme? I coundn’t access
https://github.com/jslefche/rsquared.glmer/%5D .
Can you tell me where it is, or could you please send me in an email?
Also, do you have founction/code for backward model selection for lmer?
Hi Clara, Whoops, looks like there was some gibberish at the end of the link. Try: https://github.com/jslefche/rsquared.glmer/
As for model selection, try the function ‘dredge’ in the AICcmodavg package. I’m pretty sure it has support for lmer. Cheers, Jon
Dear Jon,
I have learned so much from your papers about SEM. But when I want to download your teaching materials in this page: https://jonlefcheck.net/teaching/, it always comes an error.
So could you sent me a copy of these materials? I’ll appreciate it soooo much!
My email: wangpd@mail2.sysu.edu.cn
Hi Pandeng, hang tight, I will be updating those shortly. If it still doesn’t work, please send me an email! Cheers, Jon
Thank you so much…I learnt a lot from your sharing especially on R programming..:-)