Compare and contrast Dickinson's "The Soul selects her own Society" and Robert Frost's "Desert Places."

You have been asked to compare (think about how these poems are similar) and contrast (think about how these poems are different) in this question. As with any analytical essay about poetry, the best place to start is with an assessment of theme, mood, and style. If we look at here for each poem, we can best assess where to begin with our compare/contrast analysis.
Theme:
This is where the two poems most resemble each other. The theme of both poems, on the face of it, is isolation. However, the two poets take completely different attitudes to being alone. While Dickinson speaks of the "Soul" choosing "her own Society"--that is, closing "the Door" to all those to whom she does not want to give her "attention"--Frost's speaker is assaulted by a loneliness which "includes me unawares." While Dickinson's speaker has opted to be alone, Frost's speaker is experiencing a loneliness that strikes him to the bone; it is something that frightens him. Like Dickinson's speaker, he feels able to survive this loneliness, but this is only because his "own desert places"--the emptiness inside himself--frighten him even more than the thought of being alone among others. Evidently, this is a very different approach to being alone than Dickinson's. The moods of the two poems, therefore, are quite dissimilar. While Frost repeats the words "lonely" and "loneliness," to emphasize his disquiet with this solitude, Dickinson uses active verbs--"shut," "selects," and "close the Valves"--to emphasize the choosing of this isolation by her protagonist, who wants to resist society "like Stone."
Style:
The two poems are also quite dissimilar in stylistic terms. Frost's poem is written in regular stanzas with a consistent rhyme scheme (AABA, four lines to each stanza). This supports the theme of the poem: its monotony and predictability reflect the monotony of the loneliness about which the speaker complains. Dickinson's poem, on the other hand, uses her characteristic em dashes to add a definitiveness to the poem, but it eschews a traditional rhyme scheme. While there is assonance in the first and third lines and the second and fourth lines of each stanza, this is not true, traditional rhyme. It makes the poem more unpredictable and enforces the sense that the speaker is choosing her own way. The meter of the poem, likewise, is variable.