The value of W(i,j) is the distance between words i and j, and a row of the matrix is the vector representation of that word. Research around word vectors is all about computing W(i,j) in an efficient way that is also useful in natural language processing applications.
Word vectors are often used to compute similarity between words: since words are represented as vectors, we can compute the cosine angle between a given pair of words to find out how similar the two words are.
A google search suggests that he was born in 1961.
I ran a few queries using the code and its default dataset, trying to use neutral words for substraction: "mosquito -small +mountaineer", "mosquito -big +mountaineer", "mosquito -loud +mountaineer", "mosquito -normal +mountaineer", "mosquito -usual +mountaineer", "mosquito -air +mountaineer", "mosquito -nothing +mountaineer".
The most frequent words for these queries are: