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Let's recap what we've learned this week.
First we spoke about search, indexing, and

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ranking.
But if you will notice we.

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Left out, an important part.
While alluding to, the difficulty.

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Of, assembling.
Results, which are very large.

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At the same time ranking them efficiently.
The homework problems.

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Are related to this pro, this issue, and I
also expect that you'll have some animated

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discussion on the forum on this particular
point.

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At the same time, please don't give away
the exact answers to the homework

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questions.
Though the discussions we will certainly

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help all those having some difficulty with
the homeworks.

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Next we discussed enterprise search and
searching structured data, we found that

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it's not a solved problem and.
It's a little more difficult than

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searching.
Web data for a number of reasons.

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Finally, we turn to object search, and
covered a very important technique called

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locality sensitive hashing.
We also briefly touched upon associative

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memory, which is a related technique, but
doesn't actually store the objects.

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Now if you think about the problem of
searching for objects, and instead of

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actually wanting to find the objects which
are near your query, you only want to find

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which set of objects this is likely to
belong to.

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In some sense, you want to find the class
of objects, without worrying about the

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exact objects that are similar to one's
query.

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A bit like a associated memory.
Well, this is exactly the machine learning

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problem.
And that's we will going to get into next

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week, as you will find the approach that
we are gonna take for machine learning via

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information theory, is slightly unique and
not covered in many normal machine

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learning textbooks.
So, see you then and don't forget to

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submit your homework by Monday.
