Non parametric tests Flashcards
What are non parametric tests?
Tests which don’t assume a particular form of distribution or do not assume any parameters of the distribution.
How to carry out a sign test?
Usually using a binomial distribution to see how many values are above or below the median.Normal comparison of p value with significance level.
What is the underlying assumption required for the Wilcoxen signed rank test?
That the population distribution is symmetric about the median.The population mean will be in the same as the median if its symmetric.No normal assumption needed.
Whrn do you reject H0 in wilcoxen signed rank test?
When the value is less than equal to T.
What do the two populations have to have in common in order to do a paired wilcoxen signed rank test?
The distrubtion of the differences betwen the two random variables must be symmetric about their median difference.
What must the two samples have in common for the wilcoxen summed rank test?
Their distributions should be identically distribute apart from the median.Same shape.
For summed rank test what is m and n?
M is smaller than N.
