5 ms·
It's an example of concentration of measure: https://en.wikipedia.org/wiki/Concentration_of_measure https://en.wikipedia.org/wiki/Concentration_of_measure It's
by nybsjytm 3y ago
It's an example of concentration of measure: https://en.wikipedia.org/wiki/Concentration_of_measure https://en.wikipedia.org/wiki/Concentration_of_measure
It's easy to verify this for yourself in a simple example in something like python. Draw from a multivariate normal distribution (or almost anything) in a 1000-dimensional space and look at the norm of your vector. If you do this a lot of times you'll see that the answer is close to the same each time. This even holds true if you replace the vector norm by the distance to an arbitrary fixed point.
edit: here's some code:
import numpy
import matplotlib.pyplot
norms = []
dists = []
for i in range(5000):
vec = numpy.random.normal(size=4096)
norms.append(numpy.linalg.norm(vec))
dists.append(numpy.linalg.norm(vec-numpy.ones(4096)))
matplotlib.pyplot.hist(norms)
matplotlib.pyplot.show()
matplotlib.pyplot.hist(dists)
matplotlib.pyplot.show()
(didn't render right, sorry)
- zyklu5 3y agoCan't believe you are the only one to mention this. I thought concentration of measure would be at least mentioned to ML students right about the time they learn about the curse of dimensionality