Common-words frequencies, Shakespeare's style, and the elegy by W. S

In a 1989 book Donald W. Foster presented evidence that the style of a 1612 elegy signed "W. S." was exceptionally close to Shakespeare's on a great many quantitative measures. A re-examination of some of this evidence reveals flaws in Foster's methods. Using the frequencies of very common words, it is possible to construct an alternative style model which reliably assigns known Shakespeare poems to Shakespeare, and distinguishes these from poems by other poets. On this model the Elegy shows some resemblances with Shakespeare's but diverges from it decisively as larger and larger variable sets are used.