stacklossDistances


Mahalanobis distances were calculated using the mahalanobis R function. 
Under standard normal theory, these are approximately Chi-squared on 3 degrees of freedom.


datasets

Provides the function qqtest which incorporates uncertainty in its
qqplot display(s) so that the user might have a better sense of the
evidence against the specified distributional hypothesis.  qqtest draws a
quantile quantile plot for visually assessing whether the data come from a
test distribution that has been defined in one of many ways.  The vertical
axis plots the data quantiles, the horizontal those of a test distribution.
The default behaviour generates 1000 samples from the test distribution and
overlays the plot with shaded pointwise interval estimates for the ordered
quantiles from the test distribution.  A small number of independently
generated exemplar quantile plots can also be overlaid.  Both the interval
estimates and the exemplars provide different comparative information to
assess the evidence provided by the qqplot for or against the hypothesis
that the data come from the test distribution (default is normal or
gaussian).  Finally, a visual test of significance (a lineup plot) can also
be displayed to test the null hypothesis that the data come from the test
distribution.

Wayne Oldford

qqtest

Self Calibrating Quantile-Quantile Plots for Visual Testing

stacklossDistances function

A data frame with 21 rows and 2 variates:
<dl>
  <dt>ordinary</dt><dd>Mahalanobis squared distances from the arithemetic mean using the eliptical contours of the sample covariance matrix.</dd> <dt>robust</dt><dd>As with distances, these are Mahalobis squared distances butnow based on robust measures of location and covariance matrix (as determined from the default covRob of the robust package).</dd> </dl>

Format

"Statistical Theory and Methodology in Science and Engineering", 
K.A. Brownlee, (1960, 2nd ed. 1965), Wiley, New York pp. 491-500.

Source

Mahalanobis squared distances of Brownlee's stack loss plant operation data based only on the explanatory variates (air flow, water temperature, and acid concentration).

stacklossDistances: Mahalanobis squared distances of Brownlee's stack loss plant operation data based only on the explanatory variates (air flow, water temperature, and acid concentration).

Description

Usage

Arguments

Format

Source

Details