Questions tagged [ecology]
Ecology is the study of how organisms interact with their environment & each other. Ecology uses some specialized statistical techniques (eg ordination methods). Use this tag to indicate applications of statistics that are unique to ecology or that require a recognition of the ecological context.
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NMDS with Morisita-Horn Index: which data-transformation makes sense?
I have a community matrix of spiders, which I captured during winter in different forest stand-types.
I now want to perform an NMDs. For that I want to use the Morisita-Horn Index from R in the ...
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How to do rarefaction analysis for sample-based abundance data?
I would like to compare plant richness of different forest stands via rarefaction. The data is collected in a plot-based manner. I set 4 equal-sized plots in each stand, counted all plant individuals ...
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Environmental filtering versus spatial resampling in species distribution modeling
I am building species distribution models using machine learning models based on GBIF data (presence-only data) and working on a very large spatial scale, encompassing all of North America. Before ...
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In MVGAM, how can I model an interaction between 1 continuous variable (Abundance), 1 discrete (time in days) and 1 factor (the Genus of eukaryotes) [closed]
I'm working in microbial ecology and I'm trying to modelize the influence of the abundance of several genuses on a single genus of interest through time in a situation of primary succession of ...
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What is the best mixed model approach for a time series of animal attack records?
I have a dataset of animal attack records for Brazilian states between the years 2007 and 2022. I have three explanatory variables, which were standardized for the analyses. To incorporate the ...
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Best solution was not repeated - no reliable result for metaMDS?
I have abundance data of spiders that I captured in different forest stands and I want to perform an NMDS. It generally works, although the stress value is relatively high. However, I get the message ...
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dubious diagnostics in species distribution modeling with mgcv gam
I am doing some marine species distribution modeling with gams and mgcv in R. The diagnostics from gam.check(), and concurvity() seem dubious. Are there issues with the specification of the model, or ...
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How to Statistically Test if a Community of Species at a Particular Site is Becoming More Like Another Type of Site
I have the following data frame (I'm using R here).
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What Statistical test to use on my project?
I am very confused about what kind of statistical test to use in RStudio on my project,
I have measured the mean salinity for 3 levels of population density (low medium and high) across 6 months (...
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Transforming count data for NMDS?
I am looking at species count data. Due to large counts of certain species, I initially fourth root transformed the data. I am using Bray-Curtis distance measurement.
However when using vegan::metaMDS,...
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Is there a way to perform a Hierarchical Partitioning with NMDS in R?
I performed non-metric multidimensional scaling (NMDS) on my ecological data and I was satisfied with my results, but I was told that I should use hierarchical partitioning in my analysis to check for ...
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Should data be transformed for NMDS? [duplicate]
I am looking at species count data. Due to large counts of certain species, I initially fourth root transformed the data. However when using vegan::metaMDS-Bray Curtis distance, the stress value for ...
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Dealing with Underdispersion in Poisson Regression (GLM) with count data as a response variable
Related to glm() in R, I am working with count data (number of mammal species on islands) and following statistical theory, I have fitted a ...
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How to apply RLQ ordination to communities with different species?
I am analyzing the relationship between bird traits and environmental variation using the RLQ ordination corrected for spatial autocorrelation and phylogeny, i.e., the method in Pavoine et al. 2011
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What is a good p-value adjustment for a permutational analysis like pairwise PERMANOVA?
I am comparing plant community responses to experimental treatments using the pairwise.permanova function in R.
However, there are no clear answers regarding which ...
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