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Instructor: We will start with one of the
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simplest transformations.
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Often we are not interested
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in an absolute value, but a relative value.
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That's usually the case when working with stock prices.
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If you open Google and type Apple stock price,
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what you'll get is Apple stock price,
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but with red or green numbers,
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the relative change in Apple stock price.
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This is an example of pre-processing that is so common
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we don't consider it as such.
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Relative metrics are especially useful
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when we have a time series data, like stock prices,
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Forex exchange rates, and so on.
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Still in the world of finance,
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we can further transform these relative changes
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into logarithms.
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Many statistical and mathematical methods
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take advantage of logarithms
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as they facilitate faster computation.
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In machine learning,
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log transformations are not as common
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but can increase the speed of learning.
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Okay, great.
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So this is one type of pre-processing we wanted to give
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as an example.
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Let's continue to our next lesson,
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where we will deal with pre-processing transformations
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that are more typical for the world of machine learning.
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Stick around, and thanks for watching.
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