Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Statistical Data Analysis

Nonparametric Methods

isoreg isoreg computes the isotonic regression smoother via the Pool Adjacent Violators algorithm. Given a data set {(X_i,Y_i)} where X_i <= X_(i+1) i=1,...,n finds the values {mhat(X_i)} i=1,...,n, such that, minimizes (1/n) sum_i=1,n [Y_i) - mhat(X_i)]^2 subject to mhat(X_i) <= mhat[X_(i+1)], i=1,...,n
l1line l1line computes the least absolute deviation line from scatterplot data. It gives the estimate b0 and b1 that minimizes sum_i=1,n |y_i - b0 - b1 x_i |.
locpol locpol computes the local polynomial estimator. It is using the quartic kernel.

locpoldis locpoldis computes the local polynomial estimator without mixed terms but allows for including a linear part in the regression model. It is using the quartic kernel.

lowess lowess computes the robust locally weighted regression. Fitted values are computed at each of the given values x.
rmed rmed computes the running median of y using the optimal median smoothing algorithm od Haerdle ans Steiger (1990).
sker sker computes a direct kernel estimate without binning from scatter plot data.

sknn sknn computes the k-nearest neighbour smooth regression from scatter plot data. As inputs you have to specify the explanatory variable x, the dependent variable y and the smoothing parameter k.
spline spline fits a cubic spline to input data.

Basic Statistics

max max computes the maximal value of the elements of an array regarding a given dimension.
maxind maxind gives a row vector with the index of the maximum element in each column of a matrix. As usally this functionality extends to higher dimensional arrays.
mean mean computes the mean of the elements of an array regarding a given dimension.

min min computes the minimum value of the elements of an array regarding a given dimension.
minind minind gives a row vector with the index of the minimum element in each column of a matrix. As usally this functionality extends to higher dimensional arrays.
var var computes the variance of the elements of an array regarding a given dimension.

Graphical User Interfac

readevent readevent reads a key- or a mouse- event while a program is running. An "event" is a stroke of a key or a click of a mouse button. readevent will be mainly useful for letting XploRe know whether such an event has occured and to get some special information like the coordinates where the mouse click happened or a key code. readevent will "record" the relevant event if it ocurred previous to the moment when readevent is called. readevent can therefore be used to "tell" the program that the event has happened. Sometimes it is usefull to call at first setmode(...., 2) to disable default event handling.

Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

(C) MD*TECH Method and Data Technologies, 17.8.2000