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RomanL

Roman Luštrik

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Estimate prevalence of SARS-CoV-2 cases in Slovenia
Using maximum likelihood and bayesian methods to estimate intervals of estimated prevalence
Number of grooms and brides by age groups
See number of grooms and brides by their age groups from 1988 to 2018 in Slovenia.
What sample size to estimate infection prevelance, a simulation study
In order to ascertain prevalence of a disease, I perform a simulation on various sample sizes and prevalence values.
Ranking IDPA shooters
Ranking of shooters in a national level IDPA competition in Črnotiči (Slovenia).
Cat restaurant
Free range cats sometimes bring dinner back home.
Compare credible intervals of SC(R) models for marked and unmarked individuals
Estimating population size using spatial-capture-recapture and spatial count models through a simulation.
When will SO [r] tag reach 100.000 Qs?
I try to predict when will StackOverflow community be worth 100.000 questions.
Goodness of fit test in R, a simulation approach
In this iteration, I explore how goodness-of-fit test works in R and when can we expect a "significant" result. Use with caution.
Parametric and bootstrapped confidence intervals
Three ways of calculating confidence intervals for Poisson regression. Calulating CI on link or response yields very little difference, while bootstrapped confidence interval is narrower.
Simulate count data and analyse using NMDS
Using package coenocliner simulate community count data and visualize it in lower dimension using NMDS from the vegan package.
Simulation of t-test
As an additional exercise, we simulated two populations with different means and same standard deviation and compared them using a t-test. We repeated this many times and watched how confidence intervals behaves.
ECPR summer school (Introduction to ggplot2)
On the last day of refresher course Introduction to R, we looked at some basic features of R package ggplot2.
Vpliv lege smodnika v tulcu .357
Zanimalo nas je kako lega smodnika v tulcu vpliva na hitrost izstrelka.
Kartanje an talon
How to plot factors in a specified order in ggplot
Plotting factors in a specific order using ggplot can be tricky to unwary. I demonstrate a little trick of reordering factor levels to get the desired output.
Linear regression works
Demonstrating that linear regression works - it can "guess" our simulated parameters. This is meant as skeleton code for an upcoming workshop in R in Ljubljana (organized .
Calculating different intervals in R
How to calculate different intervals in R. We discuss prediction and confidence intervals using a simple example of linear regression.
Testing three types of gun powder scales
I tested how three precision gun powder scales compare to each other given one charge. This is by no means a comprehensive test, but a starting point.
Fitting a Michaelis-Menten model and drawing the results in R
Using package drm, fit a Michaelis-Menten (dose-response) model and visualize the result using package ggplot2.
CRAN packages network graphs
A short function to draw graphs of CRAN packages.
Testing plotKML tutorial