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Numerical Summarizations - Intro to Hadoop and MapReduce

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    Now let's move on to numerical summarizations. These are some of
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    my favorite. These are the summarizations you're going to want to use when your
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    boss says, "show me the numbers". These are the numbers you're
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    going to want to show your boss. And,
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    what kind of numerical summarizations? Well,
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    we've talked about it a bit already. We might want to do
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    a word or record count. And for a word or record count,
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    which is something you've already done with the web server log
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    files, the [UNKNOWN] just outputs the thing you're interested as the key,
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    and outputs one for the value. The reducer then chugs along, sums up the values,
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    bada bing, bada boom, problem solved. This is like the Hello World of map
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    produce. Slightly more difficult are things like
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    calculating the mean or the median, or
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    if we really want to get really fancy, the standard deviation of a set of data.
タイトル:
Numerical Summarizations - Intro to Hadoop and MapReduce
概説:

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Video Language:
English
Team:
Udacity
プロジェクト:
ud617 - Intro to Hadoop and Mapreduce
Duration:
0:49

English subtitles

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