set aStr to "This is a pinnapple."
set bStr to "This is an apple."
set cStr to "Piyomaru San Dayo."

set aRes to stringDifferenceWithAppearance(aStr, bStr, "A & B") of me
–>　　{​​​​​intersect:2, ​​​​​minus:2, ​​​​​dataLabel:"A & B"​​​}

set bRes to stringDifferenceWithAppearance(bStr, cStr, "B & C") of me
–>　　{​​​​​intersect:0, ​​​​​minus:4, ​​​​​dataLabel:"B & C"​​​}

set cRes to stringDifferenceWithAppearance(cStr, aStr, "C & A") of me
–>　　{​​​​​intersect:0, ​​​​​minus:3, ​​​​​dataLabel:"C & A"​​​}

–結果をソートする
set allRes to current application’s NSArray’s arrayWithArray:{aRes, bRes, cRes}
set aSortDesc to current application’s NSSortDescriptor’s alloc()’s initWithKey:"intersect" ascending:false
set bSortDesc to current application’s NSSortDescriptor’s alloc()’s initWithKey:"minus" ascending:true
set aSortedArray to allRes’s sortedArrayUsingDescriptors:{aSortDesc, bSortDesc}

–もっとも似ている傾向を持つデータの組み合わせ
set aMostApproximative to aSortedArray’s firstObject() as record
–>　　{​​​​​minus:2, ​​​​​dataLabel:"A & B", ​​​​​intersect:2​​​}

–文字列同士の近似傾向を、相違点と重複箇所の２つの方向から計算する
on stringDifferenceWithAppearance(aStr, bStr, aLabel)
　　set aMinus to getApproximationBetweenStrings(aStr, bStr) of me
　　set aIntersect to getApproximationBetweenStringsIntersect(aStr, bStr) of me
　　return {intersect:aIntersect, minus:aMinus, dataLabel:aLabel}
end stringDifferenceWithAppearance

–与えられた文字列同士の相違点を計算する（結果がより小さい値のデータ同士が似ている）
on getApproximationBetweenStrings(aStr, bStr)
　　set aList to current application’s NSMutableArray’s arrayWithArray:(words of aStr)
　　set bList to current application’s NSMutableArray’s arrayWithArray:(words of bStr)
　　
　　set aIndex to current application’s NSCountedSet’s alloc()’s initWithArray:aList
　　set bIndex to current application’s NSCountedSet’s alloc()’s initWithArray:bList
　　
　　aIndex’s minusSet:bIndex
　　set aRes to aIndex’s allObjects()’s |count|()
　　
　　bIndex’s minusSet:aIndex
　　set bRes to bIndex’s allObjects()’s |count|()
　　
　　if aRes ≥ bRes then
　　　　return bRes
　　else
　　　　return aRes
　　end if
end getApproximationBetweenStrings