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Leer Standardization | Basic Concepts of PCA
Principal Component Analysis
course content

Cursusinhoud

Principal Component Analysis

Principal Component Analysis

1. What is Principal Component Analysis
2. Basic Concepts of PCA
3. Model Building
4. Results Analysis

book
Standardization

Finally, let's start with the analysis of the PCA mathematical model.

First of all, we start by standardizing the data that the algorithm will work with. By standardization is meant the reduction of all continuous variables to a set where the mean will be equal to 0.

This is an important step because PCA cannot work properly if there is a variable in the dataset with a range of values ​​0-20 and 100-10,000, for example. PCA will start to "ignore" the characteristic with a small spread (0-20) and it will not be able to affect the result of the algorithm.

The formula for data standardization is very simple. Subtract the mean from the value of the variable and divide the result by the standard deviation:

The scikit-learn Python library allows us to do this in 1 line:

python
Taak

Swipe to start coding

Implement standardization of X array using the numpy functions np.mean() and np.std().

Oplossing

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Was alles duidelijk?

Hoe kunnen we het verbeteren?

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Sectie 2. Hoofdstuk 1
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book
Standardization

Finally, let's start with the analysis of the PCA mathematical model.

First of all, we start by standardizing the data that the algorithm will work with. By standardization is meant the reduction of all continuous variables to a set where the mean will be equal to 0.

This is an important step because PCA cannot work properly if there is a variable in the dataset with a range of values ​​0-20 and 100-10,000, for example. PCA will start to "ignore" the characteristic with a small spread (0-20) and it will not be able to affect the result of the algorithm.

The formula for data standardization is very simple. Subtract the mean from the value of the variable and divide the result by the standard deviation:

The scikit-learn Python library allows us to do this in 1 line:

python
Taak

Swipe to start coding

Implement standardization of X array using the numpy functions np.mean() and np.std().

Oplossing

Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 2. Hoofdstuk 1
Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Onze excuses dat er iets mis is gegaan. Wat is er gebeurd?
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