How to calculate the updated centroids of clustering?
$begingroup$
I have 100 points on a two dimentional space. Any point $i$ is defined by the coordinates $(x_i,y_i)$.
Lets say we perform Kmeans clustering over these points and generate clusters. Now, each cluster has a centroid. If now now move one point from cluster $i$ to cluster $j$, then how can I calculate the updated centroids.
In Matlab syntax:
[idx,C]=KMeans(X,10);
where X(:,1) are x-axis coordinates and X(:,2) are y-axis coordinates.
means clustering
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
$endgroup$
add a comment |
$begingroup$
I have 100 points on a two dimentional space. Any point $i$ is defined by the coordinates $(x_i,y_i)$.
Lets say we perform Kmeans clustering over these points and generate clusters. Now, each cluster has a centroid. If now now move one point from cluster $i$ to cluster $j$, then how can I calculate the updated centroids.
In Matlab syntax:
[idx,C]=KMeans(X,10);
where X(:,1) are x-axis coordinates and X(:,2) are y-axis coordinates.
means clustering
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
$endgroup$
add a comment |
$begingroup$
I have 100 points on a two dimentional space. Any point $i$ is defined by the coordinates $(x_i,y_i)$.
Lets say we perform Kmeans clustering over these points and generate clusters. Now, each cluster has a centroid. If now now move one point from cluster $i$ to cluster $j$, then how can I calculate the updated centroids.
In Matlab syntax:
[idx,C]=KMeans(X,10);
where X(:,1) are x-axis coordinates and X(:,2) are y-axis coordinates.
means clustering
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
$endgroup$
I have 100 points on a two dimentional space. Any point $i$ is defined by the coordinates $(x_i,y_i)$.
Lets say we perform Kmeans clustering over these points and generate clusters. Now, each cluster has a centroid. If now now move one point from cluster $i$ to cluster $j$, then how can I calculate the updated centroids.
In Matlab syntax:
[idx,C]=KMeans(X,10);
where X(:,1) are x-axis coordinates and X(:,2) are y-axis coordinates.
means clustering
means clustering
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
edited Dec 12 '18 at 19:16
Pierre-Guy Plamondon
8,84511739
8,84511739
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
asked Oct 26 '18 at 16:15
dipak narayanandipak narayanan
33
33
add a comment |
add a comment |
1 Answer
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$begingroup$
The cluster centroid is the mean of all data points assigned to that cluster. The variable idx will tell you which cluster each data point was assigned to. Based on this, you can compute the mean of all points in cluster $i$ after removing the point that you are going to move to cluster $j$. Similarly, you can compute the mean of all points in cluster $j$ after adding in the new point. These are your updated centroids.
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
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add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
The cluster centroid is the mean of all data points assigned to that cluster. The variable idx will tell you which cluster each data point was assigned to. Based on this, you can compute the mean of all points in cluster $i$ after removing the point that you are going to move to cluster $j$. Similarly, you can compute the mean of all points in cluster $j$ after adding in the new point. These are your updated centroids.
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
$endgroup$
add a comment |
$begingroup$
The cluster centroid is the mean of all data points assigned to that cluster. The variable idx will tell you which cluster each data point was assigned to. Based on this, you can compute the mean of all points in cluster $i$ after removing the point that you are going to move to cluster $j$. Similarly, you can compute the mean of all points in cluster $j$ after adding in the new point. These are your updated centroids.
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
$endgroup$
add a comment |
$begingroup$
The cluster centroid is the mean of all data points assigned to that cluster. The variable idx will tell you which cluster each data point was assigned to. Based on this, you can compute the mean of all points in cluster $i$ after removing the point that you are going to move to cluster $j$. Similarly, you can compute the mean of all points in cluster $j$ after adding in the new point. These are your updated centroids.
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
$endgroup$
The cluster centroid is the mean of all data points assigned to that cluster. The variable idx will tell you which cluster each data point was assigned to. Based on this, you can compute the mean of all points in cluster $i$ after removing the point that you are going to move to cluster $j$. Similarly, you can compute the mean of all points in cluster $j$ after adding in the new point. These are your updated centroids.
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
answered Dec 12 '18 at 21:10
Aditya DuaAditya Dua
1,18418
1,18418
add a comment |
add a comment |
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