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Milestone: PCA_1

This Milestone will allow you to run full PCA

Depends: MATRIX_OPERATIONS

  • Which library provides a way to compute full PCA/SVD?

  • Load the dataset ######.csv as a matrix.

  • What are the dimensions of your data matrix?

  • Compute PCA on it (use scale and centering equal to TRUE). PCA will result in 2 matrices and 1 vector.

  • Check the dimensions of the matrices and vectors from PCA.

  • How many principal components do we have for this dataset?

  • Where is stored the variance captured by each PC?

  • What does the matrix samples-by-PCs mean?

  • What does the matrix features-by-PCs mean?

  • What happens if you transpose the data matrix before computing PCA?

  • Check the dimensions of the resulting matrices and vectors from PCA.

  • How many principal components do we have for this dataset?

  • Where is stored the variance captured by each PC?

  • What does the matrix samples-by-PCs mean?

  • What does the matrix features-by-PCs mean?


Milestone: PCA_2

This Milestone will allow you to run truncated PCA

Depends: PCA

  • In the method above, we used a library to compute full PCA/SVD. However, in many cases computing all PCs takes a long time, so to compute only the first say 20 PCs, we can compute a randomised truncated PCA/SVD. Which library provides this PCA implementation?
  • Load the dataset ######.csv as a matrix.
  • What are the dimensions of your data matrix?
  • Compute PCA on it (use scale and centering equal to TRUE). PCA will result in 2 matrices and 1 vector.
  • Check the dimensions of the matrices and vectors from PCA.
  • How many principal components do we have for this dataset?
  • Where is stored the variance captured by each PC?
  • What does the matrix samples-by-PCs mean?
  • What does the matrix features-by-PCs mean?
  • What is the advantage of running truncated PCA instead of full PCA?

Milestone: PCA_3

This Milestone will allow you to get a deeper understanding of the power of PCA

Depends: PCA_2

  • How can you recreate the original data from the matrices output from PCA?
  • How can you project new points into a computed PCA? You can multiply the