Answered step by step
Verified Expert Solution
Question
1 Approved Answer
Suppose you are presented with a very large set S of real numbers, and you'd like to approximate the median of these numbers by sampling.
Suppose you are presented with a very large set S of real numbers, and you'd like to approximate the median of these numbers by sampling. You may assume all the numbers in S are distinct. Let n = |S|; we will say that a number x is an e-approximate median of S if at least (1/2 - epsilon)n numbers in S are less than x, and at least (1/2 epsilon)n numbers in S are greater than x. Consider an algorithm that works as follows. You select a subset S' S uniformly at random, compute the median of S', and return this as an approximate median of S. Show that there is an absolute constant c, independent of n, so that if you apply this algorithm with a sample S' of size c, then with probability at least.99, the number returned will be a (.05)-approximate median of S. (You may consider either the version of the algorithm that constructs S' by sampling with replacement, so that an element of S can be selected multiple times, or one without replacement.) Suppose you are presented with a very large set S of real numbers, and you'd like to approximate the median of these numbers by sampling. You may assume all the numbers in S are distinct. Let n = |S|; we will say that a number x is an e-approximate median of S if at least (1/2 - epsilon)n numbers in S are less than x, and at least (1/2 epsilon)n numbers in S are greater than x. Consider an algorithm that works as follows. You select a subset S' S uniformly at random, compute the median of S', and return this as an approximate median of S. Show that there is an absolute constant c, independent of n, so that if you apply this algorithm with a sample S' of size c, then with probability at least.99, the number returned will be a (.05)-approximate median of S. (You may consider either the version of the algorithm that constructs S' by sampling with replacement, so that an element of S can be selected multiple times, or one without replacement.)
Step by Step Solution
There are 3 Steps involved in it
Step: 1
Get Instant Access to Expert-Tailored Solutions
See step-by-step solutions with expert insights and AI powered tools for academic success
Step: 2
Step: 3
Ace Your Homework with AI
Get the answers you need in no time with our AI-driven, step-by-step assistance
Get Started