k nearest neighbor regression function
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Hi,
What is the k nearest neighbour regression function in matalb? Is only knn classification function available?
Regards
Farideh
Answers (5)
  Satadru Mukherjee
 on 10 Mar 2020
        
      Edited: Satadru Mukherjee
 on 10 Mar 2020
  
      clc
clear all
close all
x=input('Enter the x coordinates:');
y=input('Enter the y coordinates:');
z=[];
a=input('Enter the x coordinate of which , you want to predict the y value:');
k=input('Enter the k value:');
for i=1:length(x)
    z=[z abs(x(i)-a)];%difference calculation
end
temp=0;
gemp=0;
for i=1:length(z)
    for j=1:(length(z)-i)
        if(z(j)>z(j+1))
            temp=z(j);
            z(j)=z(j+1);
            z(j+1)=temp;
            gemp=y(j);
            y(j)=y(j+1);
            y(j+1)=gemp;
        end
    end
end
tuka=0;
for i=1:k
    tuka=tuka+y(i);
end
output=tuka/k
0 Comments
  Bechir EL HOSNI
 on 3 Sep 2020
        
      Edited: Bechir EL HOSNI
 on 3 Sep 2020
  
      Hi
KNN is a non parametric method used in machine learning.
We find two knid of KNN:
KNN classifier: Used in classification problem in which the ouput is a categorical variable.
KNN regression : Used in regression problem in which the output is a numerical variable.
In the context of regression problem we indentifie the first the K (Integer) nearest training points, to the observation we want to predict its output, and next we compute the average of the value of those points. The optimal value of K depend on the "Bias-Vriance tradeoff" ( a very important concept in statistic and machine learning).
Thanks.
0 Comments
  Elaheh Shamsi
 on 23 Sep 2020
        Hi
you can use this link to use KNN regression
this paper uses one type of KNN regression to make the QSAR model.
good luck
0 Comments
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