Е. Деза_ М.М. Деза. Энциклопедический словарь расстояний (2008) (1185330), страница 48
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ÑÎfl ÔÓÒÚÓÚ˚ Ï˚ ·Û‰ÂÏ Ó·˚˜ÌÓ ‡ÒÒχÚË‚‡Ú¸ ‰ËÒÍÂÚÌ˚È ‚‡Ë‡ÌÚ ÏÂÚËÍ ÚÂÓËË ‚ÂÓflÚÌÓÒÚÂÈ, Ӊ̇ÍÓ ·Óθ¯ËÌÒÚ‚Ó ËÁ ÌËı ÓÔ‰ÂÎfl˛ÚÒfl ̇ β·ÓÏ ËÁÏÂËÏÓÏ ÔÓÒÚ‡ÌÒÚ‚Â. ÑÎfl ‚ÂÓflÚÌÓÒÚÌÓÈ ÏÂÚËÍË d ÛÒÎÓ‚Ë P(X = Y) = 1 ‚˚ÔÓÎÌflÂÚÒfl ÚÓ„‰‡ Ë ÚÓθÍÓ ÚÓ„‰‡, ÍÓ„‰‡ d(X, Y) = 0. ÇÓ ÏÌÓ„ËıÒÎÛ˜‡flı ̇ ÔÓÒÚ‡ÌÒÚ‚Â ÒÓÒÚÓflÌËÈ χ Á‡‰‡ÂÚÒfl ÌÂÍÓÚÓÓ ·‡ÁÓ‚Ó ‡ÒÒÚÓflÌË ˇÒÒχÚË‚‡ÂÏÓ ‡ÒÒÚÓflÌË fl‚ÎflÂÚÒfl Â„Ó ÎËÙÚËÌ„ÓÏ Ì‡ ÔÓÒÚ‡ÌÒÚ‚Ó ‡ÒÔ‰ÂÎÂÌËÈ.Ç ÒÚ‡ÚËÒÚËÍ ÏÌÓ„Ë ËÁ Û͇Á‡ÌÌ˚ı ÌËÊ ‡ÒÒÚÓflÌËÈ ÏÂÊ‰Û ‡ÒÔ‰ÂÎÂÌËflÏËP1 Ë P2 ÔËÏÂÌfl˛ÚÒfl Í‡Í ÏÂ˚ ÒÚÂÔÂÌË Òӄ·ÒËfl ÏÂÊ‰Û ÓˆÂÌË‚‡ÂÏ˚Ï (P2 ) ËÚÂÓÂÚ˘ÂÒÍËÏ (P1 ) ‡ÒÔ‰ÂÎÂÌËflÏË.чΠÔÓ ÚÂÍÒÚÛ ÒËÏ‚ÓÎÓÏ [X] Ó·ÓÁ̇˜‡ÂÚÒfl χÚÂχÚ˘ÂÒÍÓ ÓÊˉ‡ÌË (ËÎË҉̠Á̇˜ÂÌËÂ) ÒÎÛ˜‡ÈÌÓÈ ‚Â΢ËÌ˚ ï: ‚ ‰ËÒÍÂÚÌÓÏ ÒÎÛ˜‡Â [X] =xp( x ),∑xa ‰Îfl ÌÂÔÂ˚‚ÌÓ„Ó ÒÎÛ˜‡fl [ X ] =∫xp( x )dx.
ÑËÒÔÂÒËÂÈ ï ̇Á˚‚‡ÂÚÒfl ‚Â΢Ë̇[X – [X]) 2 ]. àÒÔÓθÁÛ˛ÚÒfl Ú‡ÍÊ ӷÓÁ̇˜ÂÌËfl p X = p(x) = P(X = x), FX = F(x) == P(X ≤ x), p(x, y) = P(X = x, Y = y).14.1. êÄëëíéüçàü çÄ ëãìóÄâçõï ÇÖãàóàçÄïÇÒ ‡ÒÒÚÓflÌËfl ‚ ‰‡ÌÌÓÏ ‡Á‰ÂΠÓÔ‰ÂÎfl˛ÚÒfl ̇ ÏÌÓÊÂÒÚ‚Â Z ‚ÒÂı ÒÎÛ˜‡ÈÌ˚ı‚Â΢ËÌ Ò Ó‰ÌËÏ Ë ÚÂÏ Ê ÌÂÒÛ˘ËÏ ÏÌÓÊÂÒÚ‚ÓÏ χ; Á‰ÂÒ¸ X, Y ∈ Z.Lp -ÏÂÚË͇ ÏÂÊ‰Û ‚Â΢Ë̇ÏËLp -ÏÂÚË͇ ÏÂÊ‰Û ‚Â΢Ë̇ÏË ÂÒÚ¸ ÏÂÚË͇ ̇ Z c χ ⊂ Ë [| Z | p ] < ∞ ‰Îfl ‚ÒÂıZ ∈ , ÓÔ‰ÂÎÂÌ̇fl ͇Í([| X − Y | ])p1/ p=| x − y | p p( x, y) ( x , y ) ∈χ × χ∑1/ p.É·‚‡ 14. ê‡ÒÒÚÓflÌËfl ‚ ÚÂÓËË ‚ÂÓflÚÌÓÒÚÂÈ 213ÑÎfl p = 1, 2 Ë ∞ Ó̇ ̇Á˚‚‡ÂÚÒfl ÒÓÓÚ‚ÂÚÒÚ‚ÂÌÌÓ ËÌÊÂÌÂÌÓÈ ÏÂÚËÍÓÈ, Ò‰ÌÂÍ‚‡‰‡Ú˘ÂÒÍËÏ ‡ÒÒÚÓflÌËÂÏ Ë ‡ÒÒÚÓflÌËÂÏ ÒÛ˘ÂÒÚ‚ÂÌÌÓ„Ó ÒÛÔÂÏÛχ ÏÂʉÛÔÂÂÏÂÌÌ˚ÏË.à̉Ë͇ÚÓ̇fl ÏÂÚË͇à̉Ë͇ÚÓ̇fl ÏÂÚË͇ – ÏÂÚË͇ ̇ Z, ÓÔ‰ÂÎÂÌ̇fl ͇Í∑[1X ≠ Y ] =1x ≠ y p( x, y) =( x , y ) ∈χ × χ∑p( x, y).( x , y ) ∈χ × χ, x ≠ y(ÒÏ.
ï˝ÏÏË̄ӂ‡ ÏÂÚË͇, „Î. 1).ä ÏÂÚË͇ äË î‡Ì‡ä ÏÂÚË͇ äË î‡Ì‡ ÂÒÚ¸ ÏÂÚË͇ ä ̇ Z, ÓÔ‰ÂÎÂÌ̇fl ͇Íinf{ε > 0 : P(| X − Y |> ε ) < ε}.ùÚÓ fl‚ÎflÂÚÒfl ÒÎÛ˜‡ÂÏ d(x, y) = | X – Y | ‚ÂÓflÚÌÓÒÚÌÓ„Ó ‡ÒÒÚÓflÌËfl.K * ÏÂÚË͇ äË î‡Ì‡K * ÏÂÚË͇ äË î‡Ì‡ ÂÒÚ¸ ÏÂÚË͇ K * ̇ Z, ÓÔ‰ÂÎÂÌ̇fl ͇Í| X −Y | |x−y|=p( x, y).1+ | X − Y | ( x , y ) ∈χ × χ 1+ | x − y |∑ÇÂÓflÚÌÓÒÚÌÓ ‡ÒÒÚÓflÌËÂÑÎfl ÏÂÚ˘ÂÒÍÓ„Ó ÔÓÒÚ‡ÌÒÚ‚‡ (χ , d) ‚ÂÓflÚÌÓÒÚÌÓ ‡ÒÒÚÓflÌË ̇ ZÓÔ‰ÂÎflÂÚÒfl ͇Íinf{ε : P( d ( X , Y ) > ε ) < ε}.14.2.
êÄëëíéüçàü çÄ áÄäéçÄï êÄëèêÖÑÖãÖçàüÇÒ ‡ÒÒÚÓflÌËfl ‚ ‰‡ÌÌÓÏ ‡Á‰ÂΠÓÔ‰ÂÎfl˛ÚÒfl ̇ ÏÌÓÊÂÒÚ‚Â ‚ÒÂı Á‡ÍÓÌÓ‚‡ÒÔ‰ÂÎÂÌËfl Ú‡ÍËÏ Ó·‡ÁÓÏ, ˜ÚÓ ÒÓÓÚ‚ÂÚÒÚ‚Û˛˘Ë ÒÎÛ˜‡ÈÌ˚ ‚Â΢ËÌ˚ ËϲÚÓ‰Ë̇ÍÓ‚Ó ÏÌÓÊÂÒÚ‚Ó Á̇˜ÂÌËÈ χ; Á‰ÂÒ¸ P1 , P2 ∈ .Lp -ÏÂÚË͇ ÏÂÊ‰Û ÔÎÓÚÌÓÒÚflÏËLp -ÏÂÚË͇ ÏÂÊ‰Û ÔÎÓÚÌÓÒÚflÏË ÂÒÚ¸ ÏÂÚË͇ ̇ (‰Îfl Ò˜ÂÚÌÓ„Ó χ), ÓÔ‰ÂÎÂÌ̇fl ‰Îfl β·Ó„ p > 0 ͇Í∑x| p1 ( x ) − p2 ( x ) | p ) min(1,1 / p ) .ÑÎfl p = 1  ÔÓÎÓ‚Ë̇ ̇Á˚‚‡ÂÚÒfl ÏÂÚËÍÓÈ ÔÓÎÌÓÈ ‚‡Ë‡ˆËË (ËÎË ËÁÏÂÌflÂÏ˚χÒÒÚÓflÌËÂÏ, ‡ÒÒÚÓflÌËÂÏ ÒΉ‡).
íӘ˜̇fl ÏÂÚË͇ sup | p1 ( x ) − p2 ( x ) | ÒÓÓÚ‚ÂÚÒÚ‚ÛÂÚ p = ∞.x214ó‡ÒÚ¸ III. ê‡ÒÒÚÓflÌËfl ‚ Í·ÒÒ˘ÂÒÍÓÈ Ï‡ÚÂχÚËÍÂèÓÎÛÏÂÚË͇ å‡ı‡Î‡ÌÓ·ËÒ‡èÓÎÛÏÂÚË͇ å‡ı‡Î‡ÌÓ·ËÒ‡ (ËÎË Í‚‡‰‡Ú˘ÌÓ ‡ÒÒÚÓflÌËÂ, Í‚‡‰‡Ú˘̇flÏÂÚË͇) ÂÒÚ¸ ÔÓÎÛÏÂÚË͇fl ̇ (‰Îfl χ ⊂ n), ÓÔ‰ÂÎflÂχfl ͇Í( P1 [ X ] − P2 [ X ])T A −1 ( P1 [ X ] − P2 [ X ])‰Îfl ‰‡ÌÌÓÈ ÔÓÎÓÊËÚÂθÌÓ ÓÔ‰ÂÎeÌÌÓÈ Ï‡Úˈ˚ Ä.àÌÊÂÌÂ̇fl ÔÓÎÛÏÂÚË͇àÌÊÂÌÂÌÓÈ ÔÓÎÛÏÂÚËÍÓÈ Ì‡Á˚‚‡ÂÚÒfl ÔÓÎÛÏÂÚË͇ ̇ (‰Îfl χ ⊂ ), ÓÔ‰ÂÎÂÌ̇fl ͇Í| P1 [ X ] − P2 [ X ] | =∑x ( p1 ( x ) − p2 ( x )) .xåÂÚË͇ Ó„‡Ì˘ÂÌËfl ÔÓÚÂË ÔÓfl‰Í‡ måÂÚË͇ Ó„‡Ì˘ÂÌËfl ÔÓÚÂË ÔÓfl‰Í‡ m ÂÒÚ¸ ÏÂÚËÍÓÈ Ì‡ (‰Îfl χ ⊂ ), ÓÔ‰ÂÎÂÌ̇fl ͇Í∑t ∈supx ≥t( x − t )m( p1 ( x ) − p2 ( x )).m!åÂÚË͇ äÓÎÏÓ„ÓÓ‚‡–ëÏËÌÓ‚‡åÂÚËÍÓÈ äÓÎÏÓ„ÓÓ‚‡–ëÏËÌÓ‚‡ (ËÎË ÏÂÚËÍÓÈ äÓÎÏÓ„ÓÓ‚‡, ‡‚ÌÓÏÂÌÓÈÏÂÚËÍÓÈ) fl‚ÎflÂÚÒfl ÏÂÚË͇ ̇ (‰Îfl χ ⊂ ), ÓÔ‰ÂÎÂÌ̇fl ͇Ísup | P1 ( X ≤ x ) − P2 ( X ≤ x ) | .t ∈ê‡ÒÒÚÓflÌË äÛËÔ‡ ̇ ÓÔ‰ÂÎflÂÚÒfl ͇Ísup( P1 ( X ≤ x ) − P2 ( X ≤ x )) + sup( P2 ( X ≤ x ) − P1 ( X ≤ x ))x ∈x ∈(ÒÏ.
åÂÚË͇ èÓÏÔÂÈ˛–ù„„ÎÂÒÚÓ̇, „Î. 9).ê‡ÒÒÚÓflÌË Ä̉ÂÒÓ̇–чÎËÌ„‡ ̇ ÓÔ‰ÂÎflÂÚÒfl ͇Í| P1 ( X ≤ x ) − P2 ( X ≤ x ).x ∈ ln P1 ( X ≤ x )(1 − P1 ( X ≤ x ))supê‡ÒÒÚÓflÌË äÌÍӂ˘‡–чıÏ˚ ÓÔ‰ÂÎflÂÚÒfl ͇Ísup( P1 ( X ≤ x ) − P2 ( X ≤ x )) lnx ∈+ sup( P2 ( X ≤ x ) − P1 ( X ≤ x )) lnx ∈1+P1 ( X ≤ x )(1 − P1 ( X ≤ x ))1.P1 ( X ≤ x )(1 − P1 ( X ≤ x ))íË ‚˚¯ÂÔ˂‰ÂÌÌ˚ı ‡ÒÒÚÓflÌËfl ËÒÔÓθÁÛ˛ÚÒfl ‚ ÒÚ‡ÚËÒÚËÍ ‚ ͇˜ÂÒÚ‚Â ÒÚÂÔÂÌË Òӄ·ÒËfl, ÓÒÓ·ÂÌÌÓ ‰Îfl ‡Ò˜ÂÚ‡ ËÒÍÓ‚ÓÈ ÒÚÓËÏÓÒÚË ‚ ÙË̇ÌÒÓ‚ÓÈ ÒÙÂÂ.É·‚‡ 14.
ê‡ÒÒÚÓflÌËfl ‚ ÚÂÓËË ‚ÂÓflÚÌÓÒÚÂÈ 215ê‡ÒÒÚÓflÌË ä‡Ï‡–ÙÓÌ åËÁÂÒ‡ê‡ÒÒÚÓflÌË ä‡Ï‡–ÙÓÌ åËÁÂÒ‡ ÂÒÚ¸ ‡ÒÒÚÓflÌË ̇ (‰Îfl χ ⊂ ), ÓÔ‰ÂÎÂÌÌÓ ͇Í+∞∫( P1 ( X ≤ x ) − P2 ( X ≤ x ))2 dx.−∞éÌÓ Ô‰ÒÚ‡‚ÎflÂÚ ÒÓ·ÓÈ Í‚‡‰‡Ú L 2 -ÏÂÚËÍË ÏÂÊ‰Û ÍÛÏÛÎflÚË‚Ì˚ÏË ÙÛÌ͈ËflÏËÔÎÓÚÌÓÒÚË.åÂÚË͇ ã‚ËåÂÚË͇ ãÂ‚Ë – ÏÂÚË͇ ̇ (ÚÓθÍÓ ‰Îfl χ ⊂ ), ÓÔ‰ÂÎÂÌ̇fl ͇Íinf{ε < 0 : P1 ( X ≤ x − ε ) − ε ≤ P2 ( X ≤ x ) ≤ P1 ( X ≤ x + ε ) + ε‰Îfl β·Ó„Ó x ∈ }é̇ fl‚ÎflÂÚÒfl ÒÔˆˇθÌ˚Ï ÒÎÛ˜‡ÂÏ ÏÂÚËÍË èÓıÓÓ‚‡ ‰Îfl (χ, d) = (, | x – y |).åÂÚË͇ èÓıÓÓ‚‡ÑÎfl ÏÂÚ˘ÂÒÍÓ„Ó ÔÓÒÚ‡ÌÒÚ‚‡ (χ, d) ÏÂÚË͇ èÓıÓÓ‚‡ ̇ ÓÔ‰ÂÎflÂÚ0Òfl ͇Íinf{ε > 0 : P1 ( X ∈ B) ≤ P2 ( X ∈ B ε ) + ε Ë P2 ( X ∈ B) ≤ P1 ( X ∈ B ε ) + ε},„‰Â Ç – β·Ó ·ÓÂ΂ÒÍÓ ÔÓ‰ÏÌÓÊÂÒÚ‚Ó ÏÌÓÊÂÒÚ‚‡ χ, ‡ B ε = {x : d ( x, y) < ε,y ∈ B}.ùÚÓ Ì‡ËÏÂ̸¯Â (ÔÓ ‚ÒÂÏ ÒÓ‚ÏÂÒÚÌ˚Ï ‡ÒÔ‰ÂÎÂÌËflÏ Ô‡ (X, Y) ÒÎÛ˜‡ÈÌ˚ı ‚Â΢ËÌ ï, Y, Ú‡ÍËı ˜ÚÓ Ëı χ„Ë̇θÌ˚ÂÏË ‡ÒÔ‰ÂÎÂÌËflÏË fl‚Îfl˛ÚÒfl P1Ë P 2 ÒÓÓÚ‚ÂÚÒÚ‚ÂÌÌÓ) ‚ÂÓflÚÌÓÒÚÌÓ ‡ÒÒÚÓflÌË ÏÂÊ‰Û ÒÎÛ˜‡ÈÌ˚ÏË ‚Â΢Ë̇ÏËï Ë Y.åÂÚË͇ ч‰ÎËÑÎfl ÏÂÚ˘ÂÒÍÓ„Ó ÔÓÒÚ‡ÌÒÚ‚‡ (χ, d) ÏÂÚË͇ ч‰ÎË Ì‡ ÓÔ‰ÂÎflÂÚÒfl ͇Ísup | P1 [ f ( X )] − P2 [ f ( X )] | = supf ∈F∑f ∈F x ∈χf ( x )( p1 ( x ) − p2 ( x )) .„‰Â F = { f : χ → , || f ||∞ + Lip d ( f ) ≤ 1} Ë Lip d ( f ) =| f ( x ) − f ( y) |.d ( x, y)x≠ysupx , y ∈χ,åÂÚË͇ òÛθ„ËÑÎfl ÏÂÚ˘ÂÒÍÓ„Ó ÔÓÒÚ‡ÌÒÚ‚‡ (χ, d) ÏÂÚË͇ òÛθ„Ë Ì‡ ÓÔ‰ÂÎflÂÚÒfl Í‡Í sup | f ( x ) | p p1 ( x ))1 / p − | f ( x ) | p p2 ( x ))1 / p , f ∈F x ∈χ x ∈χ∑„‰Â F = { f : χ → , Lip d ( f ) ≤ 1} Ë Lip d ( f ) =∑| f ( x ) − f ( y) |.d ( x, y)x≠ysupx , y ∈χ,216ó‡ÒÚ¸ III.
ê‡ÒÒÚÓflÌËfl ‚ Í·ÒÒ˘ÂÒÍÓÈ Ï‡ÚÂχÚËÍÂèÓÎÛÏÂÚË͇ áÓÎÓڇ‚‡èÓÎÛÏÂÚËÍÓÈ áÓÎÓڇ‚‡ ̇Á˚‚‡ÂÚÒfl ÔÓÎÛÏÂÚË͇ ̇ , ÓÔ‰ÂÎÂÌ̇fl ͇Ísupf ∈F∑f ( x )( p1 ( x ) − p2 ( x )) ,x ∈χ„‰Â F – β·Ó ÏÌÓÊÂÒÚ‚Ó ÙÛÌ͈ËÈ (‰Îfl ÌÂÔÂ˚‚ÌÓ„Ó ÒÎÛ˜‡fl F – β·Ó ÏÌÓÊÂÒÚ‚ÓÚ‡ÍËı Ó„‡Ì˘ÂÌÌ˚ı ÌÂÔÂ˚‚Ì˚ı ÙÛÌ͈ËÈ); ÒÏ. åÂÚË͇ òÛθ„Ë, åÂÚË͇ч‰ÎË.åÂÚË͇ Ò‚ÂÚÍËèÛÒÚ¸ G – ÒÂÔ‡‡·Âθ̇fl ÎÓ͇θÌÓ ÍÓÏÔ‡ÍÚ̇fl ‡·Â΂‡ „ÛÔÔ‡ Ë ÔÛÒÚ¸ ë(G) –ÏÌÓÊÂÒÚ‚Ó ‚ÒÂı ‰ÂÈÒÚ‚ËÚÂθÌ˚ı Ó„‡Ì˘ÂÌÌ˚ı ÌÂÔÂ˚‚Ì˚È ÙÛÌ͈ËÈ Ì‡ G,ÍÓÚÓ˚ ӷ‡˘‡˛ÚÒfl ‚ ÌÛθ ‚ ·ÂÒÍÓ̘ÌÓÒÚË. á‡ÙËÍÒËÛÂÏ ÙÛÌÍˆË˛ g ∈ C(G),Ú‡ÍÛ˛ ˜ÚÓ | g | fl‚ÎflÂÚÒfl ËÌÚ„ËÛÂÏÓÈ ÔÓ ÓÚÌÓ¯ÂÌ˲ Í Ï ‡ ̇ G Ë{β ∈ G * : gˆ (β) = 0} ËÏÂÂÚ ÔÛÒÚÛ˛ ‚ÌÛÚÂÌÌÓÒÚ¸: Á‰ÂÒ¸ G* – ‰Û‡Î¸Ì‡fl „ÛÔÔ‡ ‰Îfl G Ëĝ – ÔÂÓ·‡ÁÓ‚‡ÌË î۸ ‰Îfl g.åÂÚË͇ Ò‚ÂÚÍË û͢‡ (ËÎË ÏÂÚË͇ ҄·ÊË‚‡ÌËfl) ÓÔ‰ÂÎflÂÚÒfl ‰Îfl β·˚ı‰‚Ûı ÍÓ̘Ì˚ı ÏÂ Å˝‡ ÒÓ Á̇ÍÓÏ P1 Ë P2 ̇ G ͇Ísupx ∈G∫g( xy −1 )( dP1 − dP2 )( y) | .y ∈GчÌÌÛ˛ ÏÂÚËÍÛ ÏÓÊÌÓ Ú‡ÍÊ ‡ÒÒχÚË‚‡Ú¸ Í‡Í ‡ÁÌÓÒÚ¸ Tp1 ( g) − Tp2 ( g)ÓÔ‡ÚÓÓ‚ Ò‚ÂÚÍË Ì‡ C(G), „‰Â ‰Îfl β·ÓÈ f ∈ C(G) ÓÔ‡ÚÓ Tpf(x) ÓÔ‰ÂÎflÂÚÒfl͇Í∫f ( xy −1 )dP( y).y ∈GåÂÚË͇ ÌÂÒıÓ‰ÒÚ‚‡ÑÎfl ÏÂÚ˘ÂÒÍÓ„Ó ÔÓÒÚ‡ÌÒÚ‚‡ (χ, d) ÏÂÚË͇ ÌÂÒıÓ‰ÒÚ‚‡ ̇ ÓÔ‰ÂÎflÂÚÒfl ͇Ísup{| P1 ( X ∈ B) − P2 ( X ∈ B) |: B – β·ÓÈ Á‡ÏÍÌÛÚ˚È ¯‡}.èÓÎÛÏÂÚË͇ ‰‚ÓÈÌÓ„Ó ÌÂÒıÓ‰ÒÚ‚‡èÓÎÛÏÂÚË͇ ‰‚ÓÈÌÓ„Ó ÌÂÒıÓ‰ÒÚ‚‡ ÂÒÚ¸ ÔÓÎÛÏÂÚË͇ ÏÂÊ‰Û ‡ÒÔ‰ÂÎÂÌËflÏË P 1Ë P2 , Á‡‰‡ÌÌ˚ÏË Ì‡‰ ‡ÁÌ˚ÏË ÒÂÏÂÈÒÚ‚‡ÏË 1 Ë 2 ËÁÏÂËÏ˚ı ÏÌÓÊÂÒÚ‚, ÓÔ‰ÂÎflÂχfl ÒÎÂ‰Û˛˘ËÏ Ó·‡ÁÓÏ:D( P1 , P2 ) + D( P2 , P1 ),„‰Â D( P1 , P2 ) = sup{inf{P2 (C ) : B C ∈ 2 } − P1 ( B) : B ∈ 1 } – ‡ÒıÓʉÂÌËÂ.ê‡ÒÒÚÓflÌË ã ä‡Ï‡ê‡ÒÒÚÓflÌË ã ä‡Ï‡ ÂÒÚ¸ ÔÓÎÛÏÂÚË͇ ÏÂÊ‰Û ‡ÒÔ‰ÂÎÂÌËflÏË ‚ÂÓflÚÌÓÒÚÂÈ P1Ë P 2 (Á‡‰‡ÌÌ˚ı ̇ ‡Á΢Ì˚ı ÔÓÒÚ‡ÌÒÚ‚‡ı χ 1 Ë χ2), ÓÔ‰ÂÎÂÌ̇fl ÒÎÂ‰Û˛˘ËÏÓ·‡ÁÓÏ:max{δ( P1 , P2 ), δ( P2 , P1 )},É·‚‡ 14.
ê‡ÒÒÚÓflÌËfl ‚ ÚÂÓËË ‚ÂÓflÚÌÓÒÚÂÈ 217„‰Âδ( P1 , P2 ) = infBBP1 ( X2 = x 2 ) =∑∑| BP1 ( X2 = x 2 ) − BP2 ( X2 = x 2 ) | – Ì‚flÁ͇ ã ä‡Ï‡. á‰ÂÒ¸x 2 ∈χ 2p1 ( x1 )b( x 2 | x1 ), „‰Â Ç – ‡ÒÔ‰ÂÎÂÌË ‚ÂÓflÚÌÓÒÚÂÈ Ì‡‰ χ1 × χ2 Ëx1 ∈χ1b( x 2 | x1 ) =B( X1 = x1 , X2 = x 2 )=B( X1 = x1 )B( X1 = x1 , X2 = x 2 ).B( X1 = x 2 , X2 = x )∑x ∈χ 2ëΉӂ‡ÚÂθÌÓ, BP2 ( X2 = x 2 ) fl‚ÎflÂÚÒfl ‡ÒÔ‰ÂÎÂÌËÂÏ ‚ÂÓflÚÌÓÒÚÂÈ Ì‡‰ χ2,ÔÓÒÍÓθÍÛ∑ b( x2 | x1 ) = 1. ê‡ÒÒÚÓflÌË ã ä‡Ï‡ Ì fl‚ÎflÂÚÒfl ‡ÒÒÚÓflÌËÂÏ ÚÂÓËËx 2 ∈χ 2‚ÂÓflÚÌÓÒÚÂÈ, ÔÓÒÍÓθÍÛ P1 Ë P2 Á‡‰‡Ì˚ ̇‰ ‡ÁÌ˚ÏË ÔÓÒÚ‡ÌÒÚ‚‡ÏË; ˝ÚÓ ÂÒÚ¸‡ÒÒÚÓflÌË ÏÂÊ‰Û ÒÚ‡ÚËÒÚ˘ÂÒÍËÏË ˝ÍÒÔÂËÏÂÌÚ‡ÏË (ÏÓ‰ÂÎflÏË).åÂÚË͇ ëÍÓÓıÓ‰‡–ÅËÎËÌ„ÒÎËåÂÚË͇ ëÍÓÓıÓ‰‡–ÅËÎËÌ„ÒÎË – ÏÂÚË͇ ̇ , ÓÔ‰ÂÎÂÌ̇fl ͇Íf ( y) − f ( x ) inf max sup | P1 ( X ≤ x ) − P2 ( X ≤ f ( x )) | sup | f ( x ) − x |,sup ln,fy−xxx≠y x„‰Â f: → – ÒÚÓ„Ó ‚ÓÁ‡ÒÚ‡˛˘‡fl ÌÂÔÂ˚‚̇fl ÙÛÌ͈Ëfl.åÂÚË͇ ëÍÓÓıÓ‰‡åÂÚËÍÓÈ ëÍÓÓıÓ‰‡ ̇Á˚‚‡ÂÚÒfl ÏÂÚË͇ ̇ , ÓÔ‰ÂÎÂÌ̇fl ͇Íinf ε > 0 : max sup | P1 ( X < x ) − P2 ( X ≤ f ( x )) |,sup | f ( x ) − x | < ε ,x x„‰Â f: → – ÒÚÓ„Ó ‚ÓÁ‡ÒÚ‡˛˘‡fl ÌÂÔÂ˚‚̇fl ÙÛÌ͈Ëfl.ê‡ÒÒÚÓflÌË ÅËÌ·‡Ûχ–é΢‡ê‡ÒÒÚÓflÌË ÅËÌ·‡Ûχ–é΢‡ – ‡ÒÒÚÓflÌË ̇ , ÓÔ‰ÂÎÂÌÌÓ ͇Ísup f (| P1 ( X ≤ x ) − P2 ( X ≤ x ) |),x ∈„‰Â f: ≥0 → ≥0 – β·‡fl ÌÂÛ·˚‚‡˛˘‡fl ÌÂÔÂ˚‚̇fl ÙÛÌ͈Ëfl Ò f(0) = 0 Ë f(2t) ≤ Kf(t)‰Îfl β·Ó„Ó t > 0 Ë ÌÂÍÓÚÓÓ„Ó Á‡‰‡ÌÌÓ„Ó K.
éÌÓ fl‚ÎflÂÚÒfl ÔÓ˜ÚË ÏÂÚËÍÓÈ,ÔÓÒÍÓθÍÛ Òӷ≇ÂÚÒfl ÛÒÎÓ‚Ë d ( P1 , P2 ) ≤ K ( d ( P2 , P3 ) + d ( P3 , P2 )).ê‡ÒÒÚÓflÌË ÅËÌ·‡Ûχ–é΢‡ ÔËÏÂÌflÂÚÒfl Ú‡ÍÊ ‚ ÙÛÌ͈ËÓ̇θÌÓÏ ‡Ì‡ÎËÁÂ̇ ÏÌÓÊÂÒÚ‚Â ‚ÒÂı ËÌÚ„ËÛÂÏ˚ı ÙÛÌ͈ËÈ Ì‡ ÓÚÂÁÍ [0, 1], „‰Â ÓÌÓ ÓÔ‰ÂÎflÂÚÒfl1͇Í∫H (| f ( x ) − g( x ) |)dx, „‰Â ç – ÌÂÛ·˚‚‡˛˘‡fl ÌÂÔÂ˚‚̇fl ÙÛÌ͈Ëfl ËÁ [0, ∞) ‚0[0, ∞), ÍÓÚÓ‡fl Ó·‡˘‡ÂÚÒfl ‚ ÌÛθ ‚ ÌÛÎÂ Ë Û‰Ó‚ÎÂÚ‚ÓflÂÚ ÛÒÎӂ˲ é΢‡:supt >0H (2t )< ∞.H (t )218ó‡ÒÚ¸ III.
ê‡ÒÒÚÓflÌËfl ‚ Í·ÒÒ˘ÂÒÍÓÈ Ï‡ÚÂχÚËÍÂê‡ÒÒÚÓflÌË äÛ„ÎÓ‚‡ê‡ÒÒÚÓflÌË äÛ„ÎÓ‚‡ – ‡ÒÒÚÓflÌË ̇ , ÓÔ‰ÂÎÂÌÌÓ ͇Í∫f ( P1 ( X ≤ x ) − P2 ( X ≤ x )dx,„‰Â f: ≥ 0 → ≥0 – ÒÚÓ„Ó ‚ÓÁ‡ÒÚ‡˛˘‡fl ˜eÚ̇fl ÙÛÌ͈Ëfl Ò f(0) = 0 Ë f ( s + t ) ≤≤ K ( f ( s) + f (t )) ‰Îfl β·˚ı s, t ≥ 0 Ë ÌÂÍÓÚÓÓ„Ó Á‡‰‡ÌÌÓ„Ó K ≥ 1. éÌÓ fl‚ÎflÂÚÒflÔÓ˜ÚË ÏÂÚËÍÓÈ, ÔÓÒÍÓθÍÛ Òӷ≇ÂÚÒfl ÛÒÎÓ‚Ë d ( P1 , P2 ) ≤ K ( d ( P1 , P3 ) + d ( P3 , P2 )).ê‡ÒÒÚÓflÌË ÅÛ·Ë–ê‡Óê‡ÒÒÏÓÚËÏ ÌÂÔÂ˚‚ÌÛ˛ ‚˚ÔÛÍÎÛ˛ ÙÛÌÍˆË˛ φ(t ) : (0, ∞) → Ë ÔÓÎÓÊËÏφ(0) = lim φ(t ) ∈ ( −∞, ∞].
Ç˚ÔÛÍÎÓÒÚ¸ φ ‚ΘÂÚ ÌÂÓÚˈ‡ÚÂθÌÓÒÚ¸ ÙÛÌ͈ËËt→0δ φ : [0, 1]2 → ( −∞, ∞], ÓÔ‰ÂÎÂÌÌÓÈ Í‡Í δ φ ( x, y) =φ( x ) + φ( y)x + yÂÒÎË (x, y) ≠− φ22 ≠ (0, 0) Ë δφ (0, 0) = 0.ëÓÓÚ‚ÂÚÒÚ‚Û˛˘Â ‡ÒÒÚÓflÌË ÅÛ·Ë–ê‡Ó ̇ ÓÔ‰ÂÎflÂÚÒfl ͇Í∑ δ φ ( p1 ( x ), p2 ( x )).xê‡ÒÒÚÓflÌË Å„χ̇ê‡ÒÒÏÓÚËÏ ‰ËÙÙÂÂ̈ËÛÂÏÛ˛ ‚˚ÔÛÍÎÛ˛ ÙÛÌÍˆË˛ φ(t): (0, ∞) → Ë ÔÓÎÓÊËÏ φ(0) = lim φ(t ) ∈ ( −∞, ∞]. Ç˚ÔÛÍÎÓÒÚ¸ φ ‚ΘÂÚ ÌÂÓÚˈ‡ÚÂθÌÓÒÚ¸ ÙÛÌ͈ËËt→0δ φ : [0, 1]2 → ( −∞, ∞], ÓÔ‰ÂÎÂÌÌÓÈ Í‡Í ÌÂÔÂ˚‚ÌÓ ÔÓ‰ÓÎÊÂÌË ÙÛÌ͈ËËδ φ (u, v) = φ(u) − φ( v) − φ ′( v)(u − v), 0 < u, v ≤ 1 ̇ [0, 1]2 .ëÓÓÚ‚ÂÚÒÚ‚Û˛˘Â ‡ÒÒÚÓflÌË Å„χ̇ ̇ ÓÔ‰ÂÎflÂÚÒfl ͇Ím∑ δ φ ( pi , qi )1(ÒÏ.