24 Questions 210 Answers 0 Followers
Questions related from Wim Kaijser
I was asked to analyze a "community" response and the suggested response is a dissimilarity matrix. Ecologists take a sample at different locations (i) they however want to know the change in...
13 March 2024 1,507 0 View
The p-value from the T-test is denoted as P(|T|>=t). Yet, observing a t-statistic similair or more extreme then T under H0 based on what I know does not fit with this notation. Often a small...
06 September 2023 9,979 3 View
A parameter is defined as a value of the population whereas a statistic is a value of the data, i.e., the mean can be a statistic or parameter. However, it can be quite ambiguously and the...
15 November 2022 5,181 26 View
For some smaller and less know "statistics" often no option to calculated the error or confidence intervals is given. However, this might be obtained by bootstrapping. In addition, both McElrath...
13 September 2022 4,734 3 View
Determining intervals for the common language effect size (CLES), probability of superiority (PS), Area Under the Curve (AUC) or Exceedance Probability (EP) is possible via multiple method Ruscia...
11 May 2022 6,932 4 View
I am exploring some data and and possibilities of quasibinomial GLM. The data is less than perfect. Nonetheless, the target variable can range from 0 till 1 and from my knowledge it seems okay (is...
15 September 2021 4,705 3 View
I have been wondering about this for a bit and forgive my ignorance. Consider we loath the NHST approach, but value the information the p-value gives. I consider the we have a "perfect"...
19 August 2021 7,500 6 View
I am a bit warry about asking this question regarding my ignorance and I am also not to sure if this question might bring out some emotional response. Assume I want to have an estimate on the...
05 August 2021 7,011 3 View
I have multiple models (hobby Sisyphean app: https://snwikaij.shinyapps.io/RF_macrophyte_models/) predicting (at least trying) presence/absence of riverine macrophytes. I would like to include...
03 June 2021 2,369 0 View
I try to predict the occurrence of individual aquatic plants (48 species) with Random Forest (RF) models. For this I use six explanatory variables. The datasets are highly unbalanced. Lets say...
03 May 2021 1,316 17 View
With bootstrapping you can obtain the variability of various summary statistics. Recently I came across the Bayesian bootstrap (http://www.sumsar.net/blog/2015/07/easy-bayesian-bootstrap-in-r/). I...
17 April 2021 3,607 4 View
I am trying to predict/discriminate macrophyte groups in rivers (https://snwikaij.shinyapps.io/RF_macrophyte_models). I have run out of viable options to predict groups with an "acceptable" model...
31 March 2021 4,221 5 View
Consider I have 3 groups: 1, 2 and 3. In each group I have 3 species. 1A, 1B, 1C; 2D, 2E, 2F and 3G, 3H, 3I. It is possible to predict where groups occur given some predictors. However, species in...
16 March 2021 4,197 4 View
In ecology linear regression is often used. However, the results of these regressions are used to build classification metrices (don't ask me why) and often the regression model itself is not...
02 March 2021 6,660 10 View
In ecology specific species can be used to get an indication/estimation of the environmental conditions. A simplistic example, lets assume I find a pike (Esox lucius). We know this species does...
02 February 2021 10,433 4 View
Clustered/random data are very common in data analysis. For example, if I want to model the occurrence (presence/absence) of a species over multiple countries I could suggest that the countries...
01 October 2020 768 2 View
There are numerous of different trophic classes, e.g. 3 oligotrophic, mesotrophic or eutrophic. However, you can even find more defined classifications using a smaller resolution. However, if I am...
25 June 2020 8,790 8 View
Hello, I have a question relating the p-value and confidence intervals from an ANOVA. The p-value, resulting from an ANOVA is an easy summary of statistical differences between more than two...
18 March 2020 1,354 3 View
A hypothetical example (hehe hypothesis), assume we have enough observations, apply both a “frequentist” and “Bayesian'ist'” model (e.g. linear model with Gaussian error distribution and for...
01 January 1970 5,220 59 View
Is it possible to compute credible intervals for the Common Language Effect Size (CLES)? Are there any sources on this? Did anyone else have some thoughts on this or played around with it and...
01 January 1970 5,213 19 View
Ecological data is in complex and underlying model assumptions are till certain degrees always violated. For example, assume a plant species increases in abundance (y) with a decrease in...
01 January 1970 9,867 0 View
Submerged plants are influenced by multiple factors. The main focus is hereby directed toward surface water dissolved nitrogen (N) or phosporus (P) compounds. Nonetheless, N and P seem to have...
01 January 1970 7,581 4 View
I often work with large scale datasets (1000+ samples) obtained by monitoring's programs. I have expectations about patterns (based on literature and own experience) in this dataset which I...
01 January 1970 3,993 5 View
p-values seem like the accepted standard for publishing, yet I have the feeling that many do not ponder on the use of them or know what they imply. The use of effect-sizes with corresponding...
01 January 1970 7,399 39 View
