These hints can give you a nudge if you are stuck on a problem.
I recommend trying the problems without hints for at least a couple days before you look.
If you're still stuck after looking at the hints, ask on Piazza.
Click to reveal hints.
Problem 1
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Hint 1
You'll need to run the algorithm many times and aggregate the results somehow.
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Hint 2
Outputting the mean doesn't work. Why not?
Problem 2
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Hint 1
The Chernoff bound doesn't work as well when the multiplicative error is close to 1.
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Hint 2
Try a different bound.
Problem 3
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Hint 1
Try constructing the committees one at a time.
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Hint 2
It's often easier to handle binomial distributions than other kinds of distributions. For example, if you pick set X by including every element
independently with probability p, then what is the distribution of |X|?
what is the distribution of |X intersect
Y| for any other set Y?
Problem 4
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Hint 1
Applying LLL directly seems to run into a problem.
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Hint 2
How can you get rid of the problem?