IxStat

And another one:)

Percentiles separation - IxStat Suppose you would like to have the sample enough to some percentiles not to overalp. Here is the code: quantile.CI

New post finally:)

Radar/spider web charts - IxStat Radar charts are still not so common as their other sisters and brothers. They alllow to show the differences among the groups for many variables at once. They work well if you have some kind of maximum for these variables. Also, if you don't have so many groups to compare, ideally 2-3. And if you a...

Deming regression. Still not very popular.

Deming regression - IxStat We all know the common OLS regression linear models. In this kind of models we assume that Y depends linearly on some let us assume continous predictor X plus and we account for the measurment error for Y as: Y_i=A+B*X_i, i is the index of the i-th observation on X and Y. Note that from this regress...

Mixed ANOVA in R - IxStat Suppose we have a data of the form: And we would like to know if there was any group, time, or group*time interaction effect. First we read the data and tranform it the into a long format: library(openxlsx) library(lme4) library(afex) p-values library(ggplot2) library(gtsummary) nice tables...

ROC curve-what you always wanted to know but were afraid to ask… - IxStat This post is inspired, as many of them, by the student's question. It appears that many of us use ROC curves in the analysis not really knowing what these curves are for and how they are created. The classification models have become a very popular tool and are part of many implemented widely availa...

Reposting old posts due to some technical problems.

Pairwise comparisons - IxStat Post-hoc pairwise comparisons are very common part of the data scientist daily routine. Whenever we do ANOVA or non-parametric testing with more than two groups that is inevitable. At some point you might want to have a nice visualizations of what is significant and what is not. Possibly with p-valu...

Forestplot R package – what you CAN’T do with it. - IxStat When you do meta-analysis you usually visualize your results using a so-called forest plot. The plot is automatically available in the packages denoted for meta-analysis (such as meta), but there are times you would like to plot it

New post on a new domain:)

Forestplot R package – what you CAN’T do with it. - IxStat When you do meta-analysis you usually visualize your results using a so-called forest plot. The plot is automatically available in the packages denoted for meta-analysis (such as meta), but there are times you would like to plot it

Really helpful package if you want to customize your forestplots!

Introduction to forest plots For marking the start/end points it is common to add a vertical line at the end of each whisker. In forestplot you simply specify the vertices argument:

We moved to a different .com domain!
Now it is

Interactions and why we all get them wrong? - IxStat Where the interpretation of the interaction comes from? Let us assume that we have patients in out sample and a linear model (simple or mixed). For the linear model we have an equation of the form: Y=A0+A1*X1+A2*X2+A3*X1*X2, where A0 is the intercept and A1 and A2 are the main effects of X1 and X2 r...