[R] dplyr summarize by groups

# Get mean, min, max sigma and skew by group options (digits = 3) library (ISwR data(energy) data %>% group_by(stature) %>% summarize( Mean = mean(expend), Min = min(expend), Max = max(expend), Sigma = sd(expend), Skew = skew(expend)) # Output stature Mean Min

[R] JASP vs R

Colleagues, Many of my colleagues come to me for a recommendation for statistical software. Since I am an R user, that's my typical answer. Some colleagues of mine refuse to use it because of its steep learning curve and lack of a GUI. They wanted a statistical software that's free and that had a

[R] Discriminant of a cubic polynomial

Colleagues Given the coefficients of a cubic polynomial, a,b,c,d and using discriminant_cubic <- function(a, b, c, d) { D <- 18 * a * b * c * d - 4 * b^3 * d + b^2 * c^2 - 4 * a * c^2 - 27 * a^2 * d^2 return(D) } I can find the discriminant of a cubic polynomial. Is there an R package which

[R] prop.trend.test question

Colleagues, The code for prop.trend.test is given by: function (x, n, score = seq_along(x)) { method <- "Chi-squared Test for Trend in Proportions" dname <- paste(deparse1(substitute(x)), "out of", deparse1(substitute(n)), ",\n using scores:", paste(score, collapse = " ")) x

[R] Mantel Haenszel test

Colleagues, I am trying to write a script for the Mantel Haenszel test. For the MH test, the test statistic is chi-square (MH) = (W-1) * r^2 Where W = sum of the case weights. This is straight forward. I'm having difficulty with r^2. The r^2 is the squared Pearson correlation between row and co