Stata rank descending

• The mean of an observation variable is a numerical measure of the central location of the data values. It is the sum of its data values divided by data count. Hence, for a data sample of size n, its sample mean is defined as follows:
• In This tutorial we will learn about head and tail function in R. head() function in R takes argument “n” and returns the first n rows of a dataframe or matrix, by default it returns first 6 rows. tail() function in R returns last n rows of a dataframe or matrix, by default it returns last 6 rows. we can also use slice() group of functions in dplyr package like slice_sample(),slice_head ...
• Rank and Order Conditions for Identification: Rank Condition: To derive a unique solution for β * from the reduced form model: r (πΔΔ*)=r[πΔΔ* πΔΔ1]=n *. This condition is both a necessary as well as a sufficient condition. Order Condition: For the rank condition to hold the following order condition is a necessary condition: mΔΔ≥n *
• proc logistic data=doseresp descending; model resp1 = dose; run; Here we treat dose as a continuous variable in order to test the null hypothesis of beta=0. The p-value estimate in the output is the same result for the two-sided Cochran-Armitage trend test . Testing Global Null Hypothesis: BETA=0
• Value. For sort, the result depends on the S3 method which is dispatched.If x does not have a class sort.int is used and it description applies. For classed objects which do not have a specific method the default method will be used and is equivalent to x[order(x, ...)]: this depends on the class having a suitable method for [(and also that order will work, which requires a xtfrm method).