www.gusucode.com > stats 源码程序 matlab案例代码 > stats/DetermineInfluentialObservationsUsingCovRatioExample.m
%% Determine Influential Observations Using CovRatio % This example shows how to use the |CovRatio| statistics to determine the % influential points in data. Load the sample data and define the response % and predictor variables. % Copyright 2015 The MathWorks, Inc. load hospital y = hospital.BloodPressure(:,1); X = double(hospital(:,2:5)); %% % Fit a linear regression model. mdl = fitlm(X,y); %% % Plot the |CovRatio| statistics. plotDiagnostics(mdl,'CovRatio') %% % For this example, the threshold limits are 1 + 3*5/100 = 1.15 and 1 - % 3*5/100 = 0.85. There are a few points beyond the limits, which might % be influential points. %% % Find the observations that are beyond the limits. find((mdl.Diagnostics.CovRatio)>1.15|(mdl.Diagnostics.CovRatio)<0.85)