Survival Analysis
Survival Analysis Survival analysis is a technique used when the outcome of interest is how long it takes until some outcome is reached, such as death, recurrence of a disease,…
Survival Analysis Survival analysis is a technique used when the outcome of interest is how long it takes until some outcome is reached, such as death, recurrence of a disease,…
STATISTICS CHAPTER THE TWENTY-FIRST Tests of Significance for Categorical Frequency Data Here we introduce statistical methods used to deal with categorical frequency data of the form, “The number of individuals…
and our alternative hypothesis is simply: Now, if we were to set about comparing the means5 with a t-test, a problem would arise. We can do only two at a…
So, the little squiggles aren’t all that mysterious; most stand for the same quantity in the sample and the population. Sample means begin with M, population means begin with Greek…
. When speaking to another statistician, we can say either the “mean” or the “X bar.”2 In recent years, we’ve seen a new abbreviation for the mean: M. This is…
ANDCORRELATION CHAPTER THE THIRTEENTH Simple Regression and Correlation The previous section dealt with ANOVA methods, which are suitable when the independent variable is nominal categories and the dependent variable approximates…
Algebraically: where j is the subscript for the columns (brand), I is the number of rows (in this case, 2), and n is the sample size in each cell (in…
CHAPTER THE TWENTY-SIXTH Measures of Impact This chapter introduces you to measures of “how much” of something—how many people have a disorder at any given time, how much greater a…
This is just longer than what we had before, not fundamentally different. A reasonable next step would be to graph the data. However, no one has yet come up with…
The Phi Coefficient, Contingency Coefficient, Yule’s Q and Cramer’s V The most obvious approach is to pretend that the data are actually interval and go ahead and calculate a Pearson…