Lastest published articles




survminer 0.2.4




I’m very pleased to announce survminer 0.2.4. It comes with many new features and minor changes. Install survminer with: install.packages("survminer") To load the package, type this: li...

Cox Model Assumptions




Previously, we described the basic methods for analyzing survival data, as well as, the Cox proportional hazards methods to deal with the situation where several factors impact on the surv...

Cox Proportional-Hazards Model




The Cox proportional-hazards model (Cox, 1972) is essentially a regression model commonly used statistical in medical research for investigating the association between the survival time ...

Survival Analysis Basics




Survival analysis corresponds to a set of statistical approaches used to investigate the time it takes for an event of interest to occur. Survival analysis is used in a variet...

Chi-Square Test of Independence in R




The chi-square test of independence is used to analyze the frequency table (i.e. contengency table) formed by two categorical variables. The chi-square test evaluates whether there is a ...

Hybrid hierarchical k-means clustering for optimizing clustering outputs - Unsupervised Machine Learning




1 How this article is organized 2 Required R packages 3 Data preparation 4 R function for clustering analyses 4.1 Example of k-means clustering 4.2 Example of hierarchical clustering 5...

Assessing clustering tendency: A vital issue - Unsupervised Machine Learning




1 Required packages 2 Data preparation 2.1 faithful dataset 2.2 Random uniformly distributed dataset 3 Why assessing clustering tendency? 4 Methods for assessing clustering tendency 4.1...

Bar plot of Group Means with Individual Observations




Example data sets Install ggpubr Bar plot of group means with individual informations ggpubr is great for data visualization and very easy to use for non-“R programmer”. It makes eas...

Chi-square Goodness of Fit Test in R




What is chi-square goodness of fit test? Example data and questions Statistical hypotheses R function: chisq.test() Answer to Q1: Are the colors equally common? Answer to Q2 comparing obs...

Two-Proportions Z-Test in R




What is two-proportions z-test? Research questions and statistical hypotheses Formula of the test statistic Case of large sample sizes Case of small sample sizes Compute two-proportions ...

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