PCA performs a principal component analysis on a given data matrix based on eigen values.
Version | 1.1 |
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Bundle | tools |
Categories | Multivariate Statistics |
Authors | Minna Miettinen (Minna.Miettinen@Helsinki.FI), Ville Rantanen (ville.rantanen@helsinki.fi) |
Issue tracker | View/Report issues |
Source files | component.xml analyzer.R |
Usage | Example with default values |
Name | Type | Mandatory | Description |
---|---|---|---|
matrix | CSV | Mandatory | The data matrix on which PCA is applied. |
Name | Type | Description |
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loadings | CSV | The matrix of variable loadings. |
scores | CSV | The matrix of scores on each principal component. Scores are computed by multiplying the data by the matrix of loadings. |
variation | CSV | The amount of variation in the original data explained by the principal components i.e. the standard deviations of the principal components. |
Name | Type | Default | Description |
---|---|---|---|
center | boolean | true | A logical value indicating whether the variables should be shifted to be zero centered. Centering is recommended; Mean subtraction (a.k.a. "mean centering") is necessary for performing PCA to ensure that the first principal component describes the direction of maximum variance. If mean subtraction is not performed, the first principal component will instead correspond to the mean of the data. |
direction | string | "column" | Direction of the summarization i.e. should PCA be applied row- or column-wise. The possible values are "column" and "row". |
scale | boolean | true | A logical value indicating whether the variables should be scaled to have unit variance before the analysis takes place. In general, scaling is advisable. |
seed | int | 12345 | Seed number for the pseudo random number generator |
Test case | Parameters▼ | IN matrix |
OUT loadings |
OUT scores |
OUT variation |
|
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case1 | (missing) | matrix | loadings | scores | variation | |
case2 | properties | matrix | loadings | scores | variation | |
direction = row, |