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vimeo.com/.../722088590

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    Confounding
    variables are a type of variable
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    related to a model's independent
    and dependent variables.
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    A variable must meet two conditions
    to be a confounder.
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    One, it must be correlated
    with the independent variable.
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    And two, it must be causally related
    to the dependent variable.
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    A pretty classic example
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    tasks you with collecting data on sunburns
    and ice cream consumptions.
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    If we find that ice cream consumption
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    goes up at the same time
    as instances of sunburn,
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    are we meant to conclude
    that ice cream causes sunburn?
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    One missing variable here is temperature
    as a proxy for the amount of sun
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    as a confounding variable.
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    The hotter
    it is, the more likely people are to eat
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    ice cream, as well as get a sunburn
    as they spend more time outdoors.
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    One of the challenges of modeling is
    that it is necessary to do an exhaustive
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    search for possible confounding factors,
    as their absence could lead to
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    certain algorithms to detect relationships
    that don't actually exist.
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    By the same token,
    if the confounding factor is identified,
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    but not properly handled
    by the algorithm in question,
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    they could end up
    exaggerating relationships that do exist.
Title:
vimeo.com/.../722088590
Video Language:
English
Duration:
01:30

English subtitles

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