COLLEGE101 Readings

These links will not be online, as they contain actual notes from my reading.

collocation extraction is the task of extracting n-grams from text that would co-occur next to each other more often than chance.

A combination is a choice task which shows that order does not matter.

\begin{equation} \mqty(n \\k) = \frac{n!}{k!(n-k)!} = n! \times 1 \times \frac{1}{k!} \times \frac{1}{(n-k)!} \end{equation}

This could be shown as follows: we first permute the group of people \(n\) (\(n!\)); take the first \(k\) of them (only 1 chose); we remove the overcounted order from the \(k\) subset chosen (\(\frac{1}{k!}\)),; we remove the overcounted order from the \(n-k\) subset (\(\frac{1}{(n-k)!}\)).