Another Try:“Stripes” Idea:group together pairs into an associative array (a,b)→1 (a,c→2 (a,d)→5 a→{b:1,c:2,d:5,e:3,f:2} (a,e)3 (a,f)→2 Each mapper takes a sentence: Generate all co-occurring term pairs For each term,emit a{b:countp,c:countc,d:countd... Reducers perform element-wise sum of associative arrays a→{b:1,d:5,e:3} Key:cleverly-constructed data structure a→{b:1,c:2,d:2,f:2} brings together partial results a→{b:2,c:2,d:7,e:3,f:2}◼ Idea: group together pairs into an associative array ◼ Each mapper takes a sentence: ◼ Generate all co-occurring term pairs ◼ For each term, emit a → { b: countb , c: countc , d: countd … } ◼ Reducers perform element-wise sum of associative arrays Another Try: “Stripes” (a, b) → 1 (a, c) → 2 (a, d) → 5 (a, e) → 3 (a, f) → 2 a → { b: 1, c: 2, d: 5, e: 3, f: 2 } a → { b: 1, d: 5, e: 3 } a → { b: 1, c: 2, d: 2, f: 2 } a → { b: 2, c: 2, d: 7, e: 3, f: 2 } +