t t t r r t r
play

tt tr - PowerPoint PPT Presentation

tt tr rt r r r s rst


  1. ◆♦t❡ ✿ ❈♦♠♣✉t✐♥❣ ✐s r❡❧❛t✐✈❡❧② ❡❛s②✱ s✐♥❝❡ ✐s ❛ ❝♦♥❝❛✈❡ ❢✉♥❝t✐♦♥ ♦❢ ✳ ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ■t ✐s ❡❛s② ✭✇❤②❄✮ t♦ s❡❡ t❤❛t R ( W ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ R ( W ⊗ W ) = 2 R ( W ) ∀ W. ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ I ( X 1 , X 2 ; Y 1 , Y 2 ) ≤ I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) . I ( X 1 , X 2 ; Y 1 , Y 2 ) = I ( X 1 , X 2 ; Y 1 ) + I ( X 1 , X 2 ; Y 2 | Y 1 ) = I ( X 1 , X 2 ; Y 1 ) + I ( Y 1 , X 1 , X 2 ; Y 2 ) − I ( Y 1 ; Y 2 ) = I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) − I ( Y 1 ; Y 2 ) ≤ I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) . ✹

  2. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ■t ✐s ❡❛s② ✭✇❤②❄✮ t♦ s❡❡ t❤❛t R ( W ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ R ( W ⊗ W ) = 2 R ( W ) ∀ W. ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ I ( X 1 , X 2 ; Y 1 , Y 2 ) ≤ I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) . I ( X 1 , X 2 ; Y 1 , Y 2 ) = I ( X 1 , X 2 ; Y 1 ) + I ( X 1 , X 2 ; Y 2 | Y 1 ) = I ( X 1 , X 2 ; Y 1 ) + I ( Y 1 , X 1 , X 2 ; Y 2 ) − I ( Y 1 ; Y 2 ) = I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) − I ( Y 1 ; Y 2 ) ≤ I ( X 1 ; Y 1 ) + I ( X 2 ; Y 2 ) . ◆♦t❡ ✿ ❈♦♠♣✉t✐♥❣ R ( W ) = sup p ( x ) I ( X ; Y ) ✐s r❡❧❛t✐✈❡❧② ❡❛s②✱ s✐♥❝❡ I ( X ; Y ) ✐s ❛ ❝♦♥❝❛✈❡ ❢✉♥❝t✐♦♥ ♦❢ p ( x ) ✳ ✹

  3. ❲❡ ❛r❡ ♥♦✇ ✭❢✉❧❧② ✐♠♠❡rs❡❞✮ ✐♥ ❛ ✇✐r❡❧❡ss ✇♦r❧❞ ◆❡t✇♦r❦ ♦❢ ✉s❡rs s❤❛r✐♥❣ s❛♠❡ ♠❡❞✐✉♠ ❈❧❡❛r ♥❡❡❞ t♦ ♠❛①✐♠❛❧❧② ✉t✐❧✐③❡ t❤❡ ❧✐♠✐t❡❞ r❡s♦✉r❝❡s ✭♣♦✇❡r✱ ❜❛♥❞✇✐❞t❤✱ ❡♥❡r❣②✮ ❉❡✈❡❧♦♣ ❛ s✐♠✐❧❛r ✉♥❞❡rst❛♥❞✐♥❣ ✐♥ ♥❡t✇♦r❦ s❡tt✐♥❣s ❇✉t ✇❡ ✜rst ♥❡❡❞ t♦ ❢✉❧❧② ✉♥❞❡rst❛♥❞ t❤❡ ❜❛s✐❝ ❜✉✐❧❞✐♥❣ ❜❧♦❝❦s ❙✉❝❝❡ss❡s ❚❤❡ ✈❛r✐♦✉s ✐❞❡❛s ✐♥tr♦❞✉❝❡❞ ❜② ❙❤❛♥♥♦♥ ❤❛✈❡ ❧❡❞ t♦ ❛♥ ✐♥❢♦r♠❛t✐♦♥ r❡✈♦❧✉t✐♦♥ ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❛♥❞ ✐ts ♦♣t✐♠❛❧✐t② ❤❛✈❡ ❞✐r❡❝t❧② ✐♥s♣✐r❡❞ • ▲♦✇ ❞❡♥s✐t② ♣❛r✐t② ❝❤❡❝❦ ❝♦❞❡s ✭▲❉P❈✮ • P♦❧❛r ❝♦❞❡s ⋆ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t② ✺

  4. ❙✉❝❝❡ss❡s ❚❤❡ ✈❛r✐♦✉s ✐❞❡❛s ✐♥tr♦❞✉❝❡❞ ❜② ❙❤❛♥♥♦♥ ❤❛✈❡ ❧❡❞ t♦ ❛♥ ✐♥❢♦r♠❛t✐♦♥ r❡✈♦❧✉t✐♦♥ ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❛♥❞ ✐ts ♦♣t✐♠❛❧✐t② ❤❛✈❡ ❞✐r❡❝t❧② ✐♥s♣✐r❡❞ • ▲♦✇ ❞❡♥s✐t② ♣❛r✐t② ❝❤❡❝❦ ❝♦❞❡s ✭▲❉P❈✮ • P♦❧❛r ❝♦❞❡s ⋆ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t② ❲❡ ❛r❡ ♥♦✇ ✭❢✉❧❧② ✐♠♠❡rs❡❞✮ ✐♥ ❛ ✇✐r❡❧❡ss ✇♦r❧❞ • ◆❡t✇♦r❦ ♦❢ ✉s❡rs s❤❛r✐♥❣ s❛♠❡ ♠❡❞✐✉♠ • ❈❧❡❛r ♥❡❡❞ t♦ ♠❛①✐♠❛❧❧② ✉t✐❧✐③❡ t❤❡ ❧✐♠✐t❡❞ r❡s♦✉r❝❡s ✭♣♦✇❡r✱ ❜❛♥❞✇✐❞t❤✱ ❡♥❡r❣②✮ • ❉❡✈❡❧♦♣ ❛ s✐♠✐❧❛r ✉♥❞❡rst❛♥❞✐♥❣ ✐♥ ♥❡t✇♦r❦ s❡tt✐♥❣s ⋆ ❇✉t ✇❡ ✜rst ♥❡❡❞ t♦ ❢✉❧❧② ✉♥❞❡rst❛♥❞ t❤❡ ❜❛s✐❝ ❜✉✐❧❞✐♥❣ ❜❧♦❝❦s ✺

  5. ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs t❤❛t s❛t✐s❢② ❢♦r s♦♠❡ ❀ ✐t s✉✣❝❡s t♦ ❝♦♥s✐❞❡r ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ ✳ ❆❤❧s✇❡❞❡ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❨❊❙✮ ✭❆❤❧s✇❡❞❡ ✬✼✷✮ ✶✳ ▼✉❧t✐♣❧❡ ❆❝❝❡ss ❈❤❛♥♥❡❧ ✭✉♣❧✐♥❦✮ ✭❙❤❛♥♥♦♥ ✬✻✶✮ X n 1 M 1 ❊♥❝♦❞❡r ✶ Y n ( ˆ M 1 , ˆ W ( y | x 1 , x 2 ) ❉❡❝♦❞❡r M 2 ) M 2 ❊♥❝♦❞❡r ✷ X n r❢✇✐r❡❧❡ss✲✇♦r❧❞ 2 ✻

  6. ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❨❊❙✮ ✭❆❤❧s✇❡❞❡ ✬✼✷✮ ✶✳ ▼✉❧t✐♣❧❡ ❆❝❝❡ss ❈❤❛♥♥❡❧ ✭✉♣❧✐♥❦✮ ✭❙❤❛♥♥♦♥ ✬✻✶✮ X n 1 M 1 ❊♥❝♦❞❡r ✶ Y n ( ˆ M 1 , ˆ W ( y | x 1 , x 2 ) ❉❡❝♦❞❡r M 2 ) M 2 ❊♥❝♦❞❡r ✷ X n r❢✇✐r❡❧❡ss✲✇♦r❧❞ 2 ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 ≤ I ( X 1 ; Y | X 2 , Q ) R 2 ≤ I ( X 2 ; Y | X 1 , Q ) R 1 + R 2 ≤ I ( X 1 , X 2 ; Y | Q ) ❢♦r s♦♠❡ p ( q ) p ( x 1 | q ) p ( x 2 | q ) ❀ ✐t s✉✣❝❡s t♦ ❝♦♥s✐❞❡r |Q| ≤ 2 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W ) ✳ ❆❤❧s✇❡❞❡ ✻

  7. ✭❨❊❙✮ ✭❆❤❧s✇❡❞❡ ✬✼✷✮ ✶✳ ▼✉❧t✐♣❧❡ ❆❝❝❡ss ❈❤❛♥♥❡❧ ✭✉♣❧✐♥❦✮ ✭❙❤❛♥♥♦♥ ✬✻✶✮ X n 1 M 1 ❊♥❝♦❞❡r ✶ Y n ( ˆ M 1 , ˆ W ( y | x 1 , x 2 ) ❉❡❝♦❞❡r M 2 ) M 2 ❊♥❝♦❞❡r ✷ X n r❢✇✐r❡❧❡ss✲✇♦r❧❞ 2 ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 ≤ I ( X 1 ; Y | X 2 , Q ) R 2 ≤ I ( X 2 ; Y | X 1 , Q ) R 1 + R 2 ≤ I ( X 1 , X 2 ; Y | Q ) ❢♦r s♦♠❡ p ( q ) p ( x 1 | q ) p ( x 2 | q ) ❀ ✐t s✉✣❝❡s t♦ ❝♦♥s✐❞❡r |Q| ≤ 2 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W ) ✳ ❆❤❧s✇❡❞❡ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✻

  8. ✶✳ ▼✉❧t✐♣❧❡ ❆❝❝❡ss ❈❤❛♥♥❡❧ ✭✉♣❧✐♥❦✮ ✭❙❤❛♥♥♦♥ ✬✻✶✮ X n 1 M 1 ❊♥❝♦❞❡r ✶ Y n ( ˆ M 1 , ˆ W ( y | x 1 , x 2 ) ❉❡❝♦❞❡r M 2 ) M 2 ❊♥❝♦❞❡r ✷ X n r❢✇✐r❡❧❡ss✲✇♦r❧❞ 2 ❘❛♥❞♦♠ ❝♦❞✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 ≤ I ( X 1 ; Y | X 2 , Q ) R 2 ≤ I ( X 2 ; Y | X 1 , Q ) R 1 + R 2 ≤ I ( X 1 , X 2 ; Y | Q ) ❢♦r s♦♠❡ p ( q ) p ( x 1 | q ) p ( x 2 | q ) ❀ ✐t s✉✣❝❡s t♦ ❝♦♥s✐❞❡r |Q| ≤ 2 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W ) ✳ ❆❤❧s✇❡❞❡ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❨❊❙✮ ✭❆❤❧s✇❡❞❡ ✬✼✷✮ ✻

  9. ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ � S λ ( W ) = max λR 1 + R 2 } ( R 1 ,R 2 ) ∈R ( W ) � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) = max p 1 ( x 1 ) p 2 ( x 2 ) ✼

  10. ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ � S λ ( W ) = max λR 1 + R 2 } ( R 1 ,R 2 ) ∈R ( W ) � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) = max p 1 ( x 1 ) p 2 ( x 2 ) 3 R 1 + R 2 R 1 2 R 1 + R 2 R 1 + R 2 R 2 ❙✉♣♣♦rt✐♥❣ ❤②♣❡r♣❧❛♥❡s ✼

  11. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ � S λ ( W ) = max λR 1 + R 2 } ( R 1 ,R 2 ) ∈R ( W ) � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) = max p 1 ( x 1 ) p 2 ( x 2 ) ❆s ❜❡❢♦r❡✱ R ( W ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ S λ ( W ⊗ W ) = 2 S λ ( W ) ∀ W, λ ≥ 1 . ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ ( λ − 1) I ( X 11 , X 12 ; Y 1 , Y 2 | X 21 , X 22 ) + I ( X 11 , X 12 , X 21 , X 22 ; Y 1 , Y 2 ) ≤ ( λ − 1) I ( X 11 ; Y 1 | X 21 ) + I ( X 11 , X 21 ; Y 1 ) + ( λ − 1) I ( X 12 ; Y 2 | X 22 ) + I ( X 12 , X 22 ; Y 2 ) ✼

  12. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ � S λ ( W ) = max λR 1 + R 2 } ( R 1 ,R 2 ) ∈R ( W ) � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) = max p 1 ( x 1 ) p 2 ( x 2 ) ❆s ❜❡❢♦r❡✱ R ( W ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ S λ ( W ⊗ W ) = 2 S λ ( W ) ∀ W, λ ≥ 1 . ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ ( λ − 1) I ( X 11 , X 12 ; Y 1 , Y 2 | X 21 , X 22 ) + I ( X 11 , X 12 , X 21 , X 22 ; Y 1 , Y 2 ) ≤ ( λ − 1) I ( X 11 ; Y 1 | X 21 ) + I ( X 11 , X 21 ; Y 1 ) + ( λ − 1) I ( X 12 ; Y 2 | X 22 ) + I ( X 12 , X 22 ; Y 2 ) ❖♥❡ ❝❛♥ ❡st❛❜❧✐s❤ t❤✐s ✐♥ s❛♠❡ ✇❛② ❛s ♣♦✐♥t✲t♦✲♣♦✐♥t s❡tt✐♥❣✳ ✼

  13. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ � S λ ( W ) = max λR 1 + R 2 } ( R 1 ,R 2 ) ∈R ( W ) � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) = max p 1 ( x 1 ) p 2 ( x 2 ) ❆s ❜❡❢♦r❡✱ R ( W ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ S λ ( W ⊗ W ) = 2 S λ ( W ) ∀ W, λ ≥ 1 . ❚❤❡ ❛❜♦✈❡ ❡q✉❛❧✐t② ✭❛❞❞✐t✐✈✐t②✮ ❢♦❧❧♦✇s ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ❤♦❧❞s✿ ( λ − 1) I ( X 11 , X 12 ; Y 1 , Y 2 | X 21 , X 22 ) + I ( X 11 , X 12 , X 21 , X 22 ; Y 1 , Y 2 ) ≤ ( λ − 1) I ( X 11 ; Y 1 | X 21 ) + I ( X 11 , X 21 ; Y 1 ) + ( λ − 1) I ( X 12 ; Y 2 | X 22 ) + I ( X 12 , X 22 ; Y 2 ) ◆♦t❡ ✿ ❈♦♠♣✉t✐♥❣ S λ ( W ) ✐s r❡❧❛t✐✈❡❧② ❡❛s② s✐♥❝❡ � � ( λ − 1) I ( X 1 ; Y | X 2 ) + I ( X 1 , X 2 ; Y ) ✐s ❝♦♥❝❛✈❡ ✐♥ p 1 ( x 1 ) , p 2 ( x 2 ) ✳ ✼

  14. ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ❛♥❞ r❛♥❞♦♠ ❤❛s❤✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ tr✐♣❧❡s t❤❛t s❛t✐s❢② ▼❛rt♦♥ ❢♦r s♦♠❡ ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ ✳ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❖♣❡♥✮ ✭s✐♥❝❡ ▼❛rt♦♥ ✬✼✾✮ ✷✳ ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭❞♦✇♥❧✐♥❦✮ ✭❈♦✈❡r ✬✼✷✮ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 r❢✇✐r❡❧❡ss✲✇♦r❧❞ ✽

  15. ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❖♣❡♥✮ ✭s✐♥❝❡ ▼❛rt♦♥ ✬✼✾✮ ✷✳ ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭❞♦✇♥❧✐♥❦✮ ✭❈♦✈❡r ✬✼✷✮ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 r❢✇✐r❡❧❡ss✲✇♦r❧❞ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ❛♥❞ r❛♥❞♦♠ ❤❛s❤✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ tr✐♣❧❡s ( R 0 , R 1 , R 2 ) t❤❛t s❛t✐s❢② R 0 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } R 0 + R 1 ≤ I ( U, Q ; Y 1 ) R 0 + R 2 ≤ I ( V, Q ; Y 2 ) R 0 + R 1 + R 2 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } + I ( U ; Y 1 | Q ) + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) ▼❛rt♦♥ ❢♦r s♦♠❡ p ( q, u, v, x ) ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ✽

  16. ✭❖♣❡♥✮ ✭s✐♥❝❡ ▼❛rt♦♥ ✬✼✾✮ ✷✳ ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭❞♦✇♥❧✐♥❦✮ ✭❈♦✈❡r ✬✼✷✮ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 r❢✇✐r❡❧❡ss✲✇♦r❧❞ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ❛♥❞ r❛♥❞♦♠ ❤❛s❤✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ tr✐♣❧❡s ( R 0 , R 1 , R 2 ) t❤❛t s❛t✐s❢② R 0 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } R 0 + R 1 ≤ I ( U, Q ; Y 1 ) R 0 + R 2 ≤ I ( V, Q ; Y 2 ) R 0 + R 1 + R 2 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } + I ( U ; Y 1 | Q ) + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) ▼❛rt♦♥ ❢♦r s♦♠❡ p ( q, u, v, x ) ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✽

  17. ✷✳ ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭❞♦✇♥❧✐♥❦✮ ✭❈♦✈❡r ✬✼✷✮ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 r❢✇✐r❡❧❡ss✲✇♦r❧❞ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ❛♥❞ r❛♥❞♦♠ ❤❛s❤✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ tr✐♣❧❡s ( R 0 , R 1 , R 2 ) t❤❛t s❛t✐s❢② R 0 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } R 0 + R 1 ≤ I ( U, Q ; Y 1 ) R 0 + R 2 ≤ I ( V, Q ; Y 2 ) R 0 + R 1 + R 2 ≤ min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } + I ( U ; Y 1 | Q ) + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) ▼❛rt♦♥ ❢♦r s♦♠❡ p ( q, u, v, x ) ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② ✭♦♣t✐♠❛❧✮ r❡❣✐♦♥❄ ✭❖♣❡♥✮ ✭s✐♥❝❡ ▼❛rt♦♥ ✬✼✾✮ ✽

  18. ◆♦t❡ ✿ ❈♦♠♣✉t✐♥❣ ✐s ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠✳ ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ✭ R 0 = 0 ✮ ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ S λ ( W ) = ( R 1 ,R 2 ) ∈R ( W a ,W b ) { λR 1 + R 2 } max � = max ( λ − 1) I ( U, Q ; Y 1 ) + min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } + I ( U ; Y 1 | Q ) p ( u,v,w,x ) � + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) � = min max ( λ − α ) I ( Q ; Y 1 ) + αI ( Q ; Y 2 ) + λI ( U ; Y 1 | Q ) α ∈ [0 , 1] p ( u,v,w,x ) � + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) ❆s ❜❡❢♦r❡✱ R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ S λ ( W a ⊗ W a , W b ⊗ W b ) = 2 S λ ( W a , W b ) ∀ W a , W b , λ ≥ 1 . ✾

  19. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ✭ R 0 = 0 ✮ ❉❡✜♥❡✱ ❢♦r λ ≥ 1 ✱ S λ ( W ) = ( R 1 ,R 2 ) ∈R ( W a ,W b ) { λR 1 + R 2 } max � = max ( λ − 1) I ( U, Q ; Y 1 ) + min { I ( Q ; Y 1 ) , I ( Q ; Y 2 ) } + I ( U ; Y 1 | Q ) p ( u,v,w,x ) � + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) � = min max ( λ − α ) I ( Q ; Y 1 ) + αI ( Q ; Y 2 ) + λI ( U ; Y 1 | Q ) α ∈ [0 , 1] p ( u,v,w,x ) � + I ( V ; Y 2 | Q ) − I ( U ; V | Q ) ❆s ❜❡❢♦r❡✱ R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ S λ ( W a ⊗ W a , W b ⊗ W b ) = 2 S λ ( W a , W b ) ∀ W a , W b , λ ≥ 1 . ◆♦t❡ ✿ ❈♦♠♣✉t✐♥❣ S λ ( W a , W b ) ✐s ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠✳ ✾

  20. ❈♦✈❡r ✬✼✷✿ ❞❡✈❡❧♦♣♠❡♥t ♦❢ s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ str❛t❡❣② ●❛❧❧❛❣❡r ✬✼✹✿ ❝♦♥✈❡rs❡ t♦ t❤❡ ❞❡❣r❛❞❡❞ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭ s✉❜✲❛❞❞✐t✐✈✐t② ✮ ❲❡✐♥❣❛rt❡♥✲❙t❡✐♥❜❡r❣✲❙❤❛♠❛✐ ✬✵✻✿ ❖♣t✐♠❛❧✐t② ♦❢ ✭♦♥ ✮ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❀ ❞❡✈❡❧♦♣✐♥❣ ❛ ❢❛♠✐❧② ♦❢ t✐❣❤t ❝♦♥✈❡① r❡❧❛①❛t✐♦♥s t♦ ❝♦♠♣✉t❡ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ♦❢ ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ●❡♥❣✲◆❛✐r ✬✶✹✿ ❖♣t✐♠❛❧✐t② ♦❢ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❚❡❝❤♥✐q✉❡ ❢♦r ❡st❛❜❧✐s❤✐♥❣ ❡①tr❡♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ ❞✐str✐❜✉t✐♦♥s ✉s✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❢✉♥❝t✐♦♥❛❧s ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ♦♥ R 1 = 0 ✭♦r R 2 = 0 ✮ ⋆ ❉❡❣r❛❞❡❞ ♠❡ss❛❣❡ s❡ts✿ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✼✮ • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ●❛❧❧❛❣❡r ✬✼✹✱ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✺✱ ✬✼✼✱ ✬✼✾✮✱ ●❡❧❢❛♥❞ ❛♥❞ P✐♥s❦❡r ✭✬✼✽✮✱ P♦❧t②r❡✈ ✭✬✼✽✮✱ ❊❧ ●❛♠❛❧ ✭✬✼✾✱ ✬✽✵✮ ⋆ ❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✱ ◆❛✐r ✬✶✵✱ ●❡♥❣ ❛♥❞ ●♦❤❛r✐ ❛♥❞ ◆❛✐r ❛♥❞ ❨✉ ✬✶✹✱ ●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ t❡❝❤♥✐q✉❡s ✇❡r❡ ♥❡❡❞❡❞ t♦ ❡st❛❜❧✐s❤ t❤❡s❡ ❝❛♣❛❝✐t② r❡❣✐♦♥s ✶✵

  21. ●❛❧❧❛❣❡r ✬✼✹✿ ❝♦♥✈❡rs❡ t♦ t❤❡ ❞❡❣r❛❞❡❞ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭ s✉❜✲❛❞❞✐t✐✈✐t② ✮ ❲❡✐♥❣❛rt❡♥✲❙t❡✐♥❜❡r❣✲❙❤❛♠❛✐ ✬✵✻✿ ❖♣t✐♠❛❧✐t② ♦❢ ✭♦♥ ✮ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❀ ❞❡✈❡❧♦♣✐♥❣ ❛ ❢❛♠✐❧② ♦❢ t✐❣❤t ❝♦♥✈❡① r❡❧❛①❛t✐♦♥s t♦ ❝♦♠♣✉t❡ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ♦❢ ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ●❡♥❣✲◆❛✐r ✬✶✹✿ ❖♣t✐♠❛❧✐t② ♦❢ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❚❡❝❤♥✐q✉❡ ❢♦r ❡st❛❜❧✐s❤✐♥❣ ❡①tr❡♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ ❞✐str✐❜✉t✐♦♥s ✉s✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❢✉♥❝t✐♦♥❛❧s ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ♦♥ R 1 = 0 ✭♦r R 2 = 0 ✮ ⋆ ❉❡❣r❛❞❡❞ ♠❡ss❛❣❡ s❡ts✿ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✼✮ • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ●❛❧❧❛❣❡r ✬✼✹✱ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✺✱ ✬✼✼✱ ✬✼✾✮✱ ●❡❧❢❛♥❞ ❛♥❞ P✐♥s❦❡r ✭✬✼✽✮✱ P♦❧t②r❡✈ ✭✬✼✽✮✱ ❊❧ ●❛♠❛❧ ✭✬✼✾✱ ✬✽✵✮ ⋆ ❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✱ ◆❛✐r ✬✶✵✱ ●❡♥❣ ❛♥❞ ●♦❤❛r✐ ❛♥❞ ◆❛✐r ❛♥❞ ❨✉ ✬✶✹✱ ●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ t❡❝❤♥✐q✉❡s ✇❡r❡ ♥❡❡❞❡❞ t♦ ❡st❛❜❧✐s❤ t❤❡s❡ ❝❛♣❛❝✐t② r❡❣✐♦♥s ⋆ ❈♦✈❡r ✬✼✷✿ ❞❡✈❡❧♦♣♠❡♥t ♦❢ s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ str❛t❡❣② ✶✵

  22. ❲❡✐♥❣❛rt❡♥✲❙t❡✐♥❜❡r❣✲❙❤❛♠❛✐ ✬✵✻✿ ❖♣t✐♠❛❧✐t② ♦❢ ✭♦♥ ✮ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❀ ❞❡✈❡❧♦♣✐♥❣ ❛ ❢❛♠✐❧② ♦❢ t✐❣❤t ❝♦♥✈❡① r❡❧❛①❛t✐♦♥s t♦ ❝♦♠♣✉t❡ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ♦❢ ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ●❡♥❣✲◆❛✐r ✬✶✹✿ ❖♣t✐♠❛❧✐t② ♦❢ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❚❡❝❤♥✐q✉❡ ❢♦r ❡st❛❜❧✐s❤✐♥❣ ❡①tr❡♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ ❞✐str✐❜✉t✐♦♥s ✉s✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❢✉♥❝t✐♦♥❛❧s ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ♦♥ R 1 = 0 ✭♦r R 2 = 0 ✮ ⋆ ❉❡❣r❛❞❡❞ ♠❡ss❛❣❡ s❡ts✿ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✼✮ • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ●❛❧❧❛❣❡r ✬✼✹✱ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✺✱ ✬✼✼✱ ✬✼✾✮✱ ●❡❧❢❛♥❞ ❛♥❞ P✐♥s❦❡r ✭✬✼✽✮✱ P♦❧t②r❡✈ ✭✬✼✽✮✱ ❊❧ ●❛♠❛❧ ✭✬✼✾✱ ✬✽✵✮ ⋆ ❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✱ ◆❛✐r ✬✶✵✱ ●❡♥❣ ❛♥❞ ●♦❤❛r✐ ❛♥❞ ◆❛✐r ❛♥❞ ❨✉ ✬✶✹✱ ●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ t❡❝❤♥✐q✉❡s ✇❡r❡ ♥❡❡❞❡❞ t♦ ❡st❛❜❧✐s❤ t❤❡s❡ ❝❛♣❛❝✐t② r❡❣✐♦♥s ⋆ ❈♦✈❡r ✬✼✷✿ ❞❡✈❡❧♦♣♠❡♥t ♦❢ s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ str❛t❡❣② ⋆ ●❛❧❧❛❣❡r ✬✼✹✿ ❝♦♥✈❡rs❡ t♦ t❤❡ ❞❡❣r❛❞❡❞ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭ s✉❜✲❛❞❞✐t✐✈✐t② ✮ ✶✵

  23. ●❡♥❣✲◆❛✐r ✬✶✹✿ ❖♣t✐♠❛❧✐t② ♦❢ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❚❡❝❤♥✐q✉❡ ❢♦r ❡st❛❜❧✐s❤✐♥❣ ❡①tr❡♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ ❞✐str✐❜✉t✐♦♥s ✉s✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❢✉♥❝t✐♦♥❛❧s ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ♦♥ R 1 = 0 ✭♦r R 2 = 0 ✮ ⋆ ❉❡❣r❛❞❡❞ ♠❡ss❛❣❡ s❡ts✿ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✼✮ • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ●❛❧❧❛❣❡r ✬✼✹✱ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✺✱ ✬✼✼✱ ✬✼✾✮✱ ●❡❧❢❛♥❞ ❛♥❞ P✐♥s❦❡r ✭✬✼✽✮✱ P♦❧t②r❡✈ ✭✬✼✽✮✱ ❊❧ ●❛♠❛❧ ✭✬✼✾✱ ✬✽✵✮ ⋆ ❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✱ ◆❛✐r ✬✶✵✱ ●❡♥❣ ❛♥❞ ●♦❤❛r✐ ❛♥❞ ◆❛✐r ❛♥❞ ❨✉ ✬✶✹✱ ●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ t❡❝❤♥✐q✉❡s ✇❡r❡ ♥❡❡❞❡❞ t♦ ❡st❛❜❧✐s❤ t❤❡s❡ ❝❛♣❛❝✐t② r❡❣✐♦♥s ⋆ ❈♦✈❡r ✬✼✷✿ ❞❡✈❡❧♦♣♠❡♥t ♦❢ s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ str❛t❡❣② ⋆ ●❛❧❧❛❣❡r ✬✼✹✿ ❝♦♥✈❡rs❡ t♦ t❤❡ ❞❡❣r❛❞❡❞ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭ s✉❜✲❛❞❞✐t✐✈✐t② ✮ ⋆ ❲❡✐♥❣❛rt❡♥✲❙t❡✐♥❜❡r❣✲❙❤❛♠❛✐ ✬✵✻✿ ❖♣t✐♠❛❧✐t② ♦❢ R ( W a , W b ) ✭♦♥ R 0 = 0 ✮ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❀ ❞❡✈❡❧♦♣✐♥❣ ❛ ❢❛♠✐❧② ♦❢ t✐❣❤t ❝♦♥✈❡① r❡❧❛①❛t✐♦♥s t♦ ❝♦♠♣✉t❡ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ♦❢ ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ✶✵

  24. ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ♦♥ R 1 = 0 ✭♦r R 2 = 0 ✮ ⋆ ❉❡❣r❛❞❡❞ ♠❡ss❛❣❡ s❡ts✿ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✼✮ • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ●❛❧❧❛❣❡r ✬✼✹✱ ❑♦r♥❡r ❛♥❞ ▼❛rt♦♥ ✭✬✼✺✱ ✬✼✼✱ ✬✼✾✮✱ ●❡❧❢❛♥❞ ❛♥❞ P✐♥s❦❡r ✭✬✼✽✮✱ P♦❧t②r❡✈ ✭✬✼✽✮✱ ❊❧ ●❛♠❛❧ ✭✬✼✾✱ ✬✽✵✮ ⋆ ❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✱ ◆❛✐r ✬✶✵✱ ●❡♥❣ ❛♥❞ ●♦❤❛r✐ ❛♥❞ ◆❛✐r ❛♥❞ ❨✉ ✬✶✹✱ ●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ t❡❝❤♥✐q✉❡s ✇❡r❡ ♥❡❡❞❡❞ t♦ ❡st❛❜❧✐s❤ t❤❡s❡ ❝❛♣❛❝✐t② r❡❣✐♦♥s ⋆ ❈♦✈❡r ✬✼✷✿ ❞❡✈❡❧♦♣♠❡♥t ♦❢ s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ str❛t❡❣② ⋆ ●❛❧❧❛❣❡r ✬✼✹✿ ❝♦♥✈❡rs❡ t♦ t❤❡ ❞❡❣r❛❞❡❞ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✭ s✉❜✲❛❞❞✐t✐✈✐t② ✮ ⋆ ❲❡✐♥❣❛rt❡♥✲❙t❡✐♥❜❡r❣✲❙❤❛♠❛✐ ✬✵✻✿ ❖♣t✐♠❛❧✐t② ♦❢ R ( W a , W b ) ✭♦♥ R 0 = 0 ✮ ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❀ ❞❡✈❡❧♦♣✐♥❣ ❛ ❢❛♠✐❧② ♦❢ t✐❣❤t ❝♦♥✈❡① r❡❧❛①❛t✐♦♥s t♦ ❝♦♠♣✉t❡ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ♦❢ ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ⋆ ●❡♥❣✲◆❛✐r ✬✶✹✿ ❖♣t✐♠❛❧✐t② ♦❢ R ( W a , W b ) ❢♦r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❚❡❝❤♥✐q✉❡ ❢♦r ❡st❛❜❧✐s❤✐♥❣ ❡①tr❡♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ ❞✐str✐❜✉t✐♦♥s ✉s✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❢✉♥❝t✐♦♥❛❧s ✶✵

  25. ✸✳ ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❆❤❧s✇❡❞❡ ✬✼✹✮ ❈r❡❞✐t✿ ✇✇✇✳♣❡rs♦♥❛❧✳♣s✉✳❡❞✉✴❜①❣✷✶✺✴r❡s❡❛r❝❤✳❤t♠❧ X n Y n 1 1 ˆ M 1 W a ( y 1 | x 1 , x 2 ) ❊♥❝♦❞❡r ✶ ❉❡❝♦❞❡r ✶ M 1 Y n 2 ˆ W b ( y 2 | x 1 , x 2 ) M 2 ❊♥❝♦❞❡r ✷ ❉❡❝♦❞❡r ✷ M 2 X n 2 ✶✶

  26. ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥❄ ✸✳ ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❆❤❧s✇❡❞❡ ✬✼✹✮ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣✱ ♠❡ss❛❣❡ s♣❧✐tt✐♥❣✱ ❝♦❞❡❞ t✐♠❡✲s❤❛r✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < I ( X 2 ; Y 2 | U 1 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | U 1 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , ❍❛♥ 2 R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , R 1 + 2 R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) + I ( X 1 , U 2 ; Y 1 | U 1 , Q ) ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( u 1 , x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 1 | ≤ | X 1 | + 4 ✱ | U 2 | ≤ | X 2 | + 4 ✱ ❛♥❞ | Q | ≤ 7 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ❑♦❜❛②❛s❤✐ ✶✶

  27. ✸✳ ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❆❤❧s✇❡❞❡ ✬✼✹✮ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣✱ ♠❡ss❛❣❡ s♣❧✐tt✐♥❣✱ ❝♦❞❡❞ t✐♠❡✲s❤❛r✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < I ( X 2 ; Y 2 | U 1 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | U 1 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , ❍❛♥ 2 R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , R 1 + 2 R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) + I ( X 1 , U 2 ; Y 1 | U 1 , Q ) ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( u 1 , x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 1 | ≤ | X 1 | + 4 ✱ | U 2 | ≤ | X 2 | + 4 ✱ ❛♥❞ | Q | ≤ 7 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥❄ ❑♦❜❛②❛s❤✐ ✶✶

  28. ✸✳ ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❆❤❧s✇❡❞❡ ✬✼✹✮ ❙✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣✱ ♠❡ss❛❣❡ s♣❧✐tt✐♥❣✱ ❝♦❞❡❞ t✐♠❡✲s❤❛r✐♥❣ ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛❝❤✐❡✈❡ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) t❤❛t s❛t✐s❢② R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < I ( X 2 ; Y 2 | U 1 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | U 1 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , ❍❛♥ 2 R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , R 1 + 2 R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) + I ( X 1 , U 2 ; Y 1 | U 1 , Q ) ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( u 1 , x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 1 | ≤ | X 1 | + 4 ✱ | U 2 | ≤ | X 2 | + 4 ✱ ❛♥❞ | Q | ≤ 7 ✳ ❈❛❧❧ t❤✐s r❡❣✐♦♥ R ( W a , W b ) ✳ ◗✉❡st✐♦♥ ✿ ■s t❤✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥❄ ❍❛❞ ❜❡❡♥ ♦♣❡♥ ✭s✐♥❝❡ ❍❛♥ ❛♥❞ ❑♦❜❛②❛s❤✐ ✬✽✶✮ ❑♦❜❛②❛s❤✐ ✶✶

  29. ✐s ♥♦t ♦♣t✐♠❛❧ ✐♥ ❣❡♥❡r❛❧ ✭◆❛✐r✱ ❳✐❛✱ ❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮ ❇r♦❛❞❝❛st ❛♥❞ ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s ❛r❡ ❢❛r t♦♦ ✐♠♣♦rt❛♥t ❚♦ ❧❡t ♥♦♥✲❝♦♥✈❡①✐t② ❞✐ss✉❛❞❡ ✉s ❚♦ ♥♦t ✐♥✈❡st✐❣❛t❡ s✐♠♣❧❡ ❝❧❛ss❡s t❤❛t r❡q✉✐r❡ ♥❡✇ ✐❞❡❛s ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ❈❛r❧❡✐❛❧ ✬✼✺✱ ❙❛t♦ ✬✽✶✱ ❊❧ ●❛♠❛❧ ❛♥❞ ❈♦st❛ ✭✬✽✶ ❛♥❞ ✬✽✻✮ • R ( W a , W b ) ✐s ❝❧♦s❡ t♦ ♦♣t✐♠❛❧ ❢♦r ●❛✉ss✐❛♥ ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ⋆ ❊t❦✐♥ ❛♥❞ ❚s❡ ❛♥❞ ❲❛♥❣ ✭✬✵✾✮ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ ♠❛t❤❡♠❛t✐❝❛❧ r❡s✉❧ts ❝❛♠❡ ♦✉t ❢r♦♠ t❤❡ ✐♥✈❡st✐❣❛t✐♦♥ ♦❢ ♦♣t✐♠❛❧✐t② ⋆ ❈♦♥❝❛✈✐t② ♦❢ ❡♥tr♦♣② ♣♦✇❡r ✭❈♦st❛ ✬✽✺✮ ⋆ ●❡♥✐❡ ❜❛s❡❞ ❛♣♣r♦❛❝❤ t♦ ♣r♦✈❡ s✉❜✲❛❞❞✐t✐✈✐t② ✭❊❧ ●❛♠❛❧ ❛♥❞ ❈♦st❛ ✬✽✶✱ ❑r❛♠❡r ✬✵✷✮ ✶✷

  30. ❙✉❝❝❡ss❡s ■♥ s♣✐t❡ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ♣r♦❜❧❡♠ ❜❡✐♥❣ ✐♥tr✐♥s✐❝❛❧❧② ♥♦♥✲❝♦♥✈❡① • R ( W a , W b ) ✐s ♦♣t✐♠❛❧ ❢♦r s♦♠❡ ❝❧❛ss❡s ♦❢ ❝❤❛♥♥❡❧s ⋆ ❈❛r❧❡✐❛❧ ✬✼✺✱ ❙❛t♦ ✬✽✶✱ ❊❧ ●❛♠❛❧ ❛♥❞ ❈♦st❛ ✭✬✽✶ ❛♥❞ ✬✽✻✮ • R ( W a , W b ) ✐s ❝❧♦s❡ t♦ ♦♣t✐♠❛❧ ❢♦r ●❛✉ss✐❛♥ ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ⋆ ❊t❦✐♥ ❛♥❞ ❚s❡ ❛♥❞ ❲❛♥❣ ✭✬✵✾✮ • ◆♦✈❡❧ ✐❞❡❛s ❛♥❞ ♠❛t❤❡♠❛t✐❝❛❧ r❡s✉❧ts ❝❛♠❡ ♦✉t ❢r♦♠ t❤❡ ✐♥✈❡st✐❣❛t✐♦♥ ♦❢ ♦♣t✐♠❛❧✐t② ⋆ ❈♦♥❝❛✈✐t② ♦❢ ❡♥tr♦♣② ♣♦✇❡r ✭❈♦st❛ ✬✽✺✮ ⋆ ●❡♥✐❡ ❜❛s❡❞ ❛♣♣r♦❛❝❤ t♦ ♣r♦✈❡ s✉❜✲❛❞❞✐t✐✈✐t② ✭❊❧ ●❛♠❛❧ ❛♥❞ ❈♦st❛ ✬✽✶✱ ❑r❛♠❡r ✬✵✷✮ • R ( W a , W b ) ✐s ♥♦t ♦♣t✐♠❛❧ ✐♥ ❣❡♥❡r❛❧ ✭◆❛✐r✱ ❳✐❛✱ ❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮ ❇r♦❛❞❝❛st ❛♥❞ ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s ❛r❡ ❢❛r t♦♦ ✐♠♣♦rt❛♥t • ❚♦ ❧❡t ♥♦♥✲❝♦♥✈❡①✐t② ❞✐ss✉❛❞❡ ✉s • ❚♦ ♥♦t ✐♥✈❡st✐❣❛t❡ s✐♠♣❧❡ ❝❧❛ss❡s t❤❛t r❡q✉✐r❡ ♥❡✇ ✐❞❡❛s ✶✷

  31. ❆ ❝❧❛ss ♦❢ ♦♣❡♥ ♣r♦❜❧❡♠s ❆ s✉❜✲❝♦❧❧❡❝t✐♦♥ ♦❢ t❤❡ ✶✺ ♦♣❡♥ ♣r♦❜❧❡♠s ❧✐st❡❞ ✐♥ ❈❤❛♣s✳ ✺✲✾✳ ✺✳✶ ❲❤❛t ✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ ❧❡ss ♥♦✐s② ❜r♦❛❞❝❛st✲❝❤❛♥♥❡❧s ✇✐t❤ ❢♦✉r ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✭t✇♦✲r❡❝❡✐✈❡r✿ ❑♦r♥❡r✲▼❛rt♦♥ ✬✼✻✱ t❤r❡❡✲r❡❝❡✐✈❡r✿ ◆❛✐r✲❲❛♥❣ ✬✶✵✮ ✺✳✷ ❲❤❛t ✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ ♠♦r❡ ❝❛♣❛❜❧❡ ❜r♦❛❞❝❛st✲❝❤❛♥♥❡❧s ✇✐t❤ t❤r❡❡ ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✭t✇♦✲r❡❝❡✐✈❡r✿ ❊❧ ●❛♠❛❧ ✬✼✾✮ ✻✳✶ ❲❤❛t ✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ t❤❡ ●❛✉ss✐❛♥ ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ✇✐t❤ ✇❡❛❦ ✐♥t❡r❢❡r❡♥❝❡❄ ✭str♦♥❣✲✐♥t❡r❢❡r❡♥❝❡✿ ❙❛t♦ ✬✼✾❀ ♠✐①❡❞✲✐♥t❡r❢❡r❡♥❝❡ ❝♦r♥❡r✲♣♦✐♥ts✿ ❙❛t♦✬ ✽✶✱ ❈♦st❛✬✽✺❀ ✇❡❛❦✲✐♥t❡r❢❡r❡♥❝❡ ❝♦r♥❡r✲♣♦✐♥ts✿ r❛t❡✲s✉♠ ✭♣❛rt✐❛❧✮✿ t❤r❡❡✲❣r♦✉♣s ✬✵✾ ✮ ✻✳✹ ■s t❤❡ ❍❛♥✲❑♦❜❛②❛s❤✐ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s❄ ✽✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r t❤❡ ❣❡♥❡r❛❧ ✸✲r❡❝❡✐✈❡r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ♦♥❡ ♠❡ss❛❣❡ t♦ ❛❧❧ t❤r❡❡ r❡❝❡✐✈❡rs ❛♥❞ ❛♥♦t❤❡r ♠❡ss❛❣❡ t♦ t✇♦ r❡❝❡✐✈❡rs❄ ✽✳✸ ❲❤❛t ✐s t❤❡ s✉♠✲❝❛♣❛❝✐t② ♦❢ t❤❡ ❜✐♥❛r② s❦❡✇✲s②♠♠❡tr✐❝ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ✽✳✹ ■s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s❄ ✾✳✷ ❈❛♥ t❤❡ ❝♦♥✈❡rs❡ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ❜❡ ♣r♦✈❡❞ ❞✐r❡❝t❧② ❜② ♦♣t✐♠✐③✐♥❣ t❤❡ ◆❛✐r✲❊❧ ●❛♠❛❧ ♦✉t❡r ❜♦✉♥❞❄ ✾✳✸ ❲❤❛t ✐s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ t❤❡ ✷✲r❡❝❡✐✈❡r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ❝♦♠♠♦♥ ♠❡ss❛❣❡❄ ✶✸

  32. ❆ ❝❧❛ss ♦❢ ♦♣❡♥ ♣r♦❜❧❡♠s ▼② r❡❢♦r♠✉❧❛t✐♦♥s ♦❢ ❛ ❢❡✇ ♦❢ t❤❡♠✳ ✺✳✶ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r ❧❡ss✲♥♦✐s② ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ✇✐t❤ ❢♦✉r ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✺✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r ♠♦r❡✲❝❛♣❛❜❧❡ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ✇✐t❤ t❤r❡❡ ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✻✳✶ ■s t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ s❝❤❡♠❡ ✇✐t❤ ●❛✉ss✐❛♥ s✐❣♥❛❧✐♥❣ t✐❣❤t ❢♦r t❤❡ ●❛✉ss✐❛♥ ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ✇✐t❤ ✇❡❛❦ ✐♥t❡r❢❡r❡♥❝❡❄ ✻✳✹ ■s t❤❡ ❍❛♥✲❑♦❜❛②❛s❤✐ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s❄ ✽✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r t❤❡ ❣❡♥❡r❛❧ ✸✲r❡❝❡✐✈❡r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ♦♥❡ ♠❡ss❛❣❡ t♦ ❛❧❧ t❤r❡❡ r❡❝❡✐✈❡rs ❛♥❞ ❛♥♦t❤❡r ♠❡ss❛❣❡ t♦ t✇♦ r❡❝❡✐✈❡rs❄ ✽✳✸ ❉♦❡s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ ❛❝❤✐❡✈❡ t❤❡ s✉♠✲❝❛♣❛❝✐t② ♦❢ t❤❡ ❜✐♥❛r② s❦❡✇✲s②♠♠❡tr✐❝ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ✽✳✹ ■s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s❄ ✾✳✷ ❈❛♥ t❤❡ ❝♦♥✈❡rs❡ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ❜❡ ♣r♦✈❡❞ ❞✐r❡❝t❧② ❜② ♦♣t✐♠✐③✐♥❣ t❤❡ ◆❛✐r✲❊❧ ●❛♠❛❧ ♦✉t❡r ❜♦✉♥❞❄ ✾✳✸ ❉♦❡s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ ❛❝❤✐❡✈❡ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ t❤❡ ✷✲r❡❝❡✐✈❡r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ❝♦♠♠♦♥ ♠❡ss❛❣❡❄ ✶✸

  33. ❚❤❡ ❝♦♠♠♦♥ t❤❡♠❡ t♦ t❤❡s❡ ✭r❡❢♦r♠✉❧❛t❡❞✮ q✉❡st✐♦♥s ❈♦♠♠♦♥ t❤❡♠❡ ■s ❛ ❝❛♥❞✐❞❛t❡ r❛t❡ r❡❣✐♦♥ ♦♣t✐♠❛❧❄ ■❞❡❛ ❢♦r t❡st✐♥❣ ♦♣t✐♠❛❧✐t②✿ • S λ ( W ⊗ W ) ? = 2 S λ ( W ) • ❉❡t❡r♠✐♥❡ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ ❛♥ ❛ss♦❝✐❛t❡❞ ♥♦♥✲❝♦♥✈❡① ❢✉♥❝t✐♦♥❛❧ ✶✹

  34. ❙t❛t✉s ♦❢ t❤❡ ♦♣❡♥ ♣r♦❜❧❡♠s ✺✳✶ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r ❧❡ss✲♥♦✐s② ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ✇✐t❤ ❢♦✉r ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✭❖P❊◆✮ ✺✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r ♠♦r❡✲❝❛♣❛❜❧❡ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ✇✐t❤ t❤r❡❡ ♦r ♠♦r❡ r❡❝❡✐✈❡rs❄ ✭ ◆❖ ✿ ◆❛✐r✲❳✐❛ ✬✶✷✮ ✻✳✶ ■s t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ s❝❤❡♠❡ ✇✐t❤ ●❛✉ss✐❛♥ s✐❣♥❛❧✐♥❣ t✐❣❤t ❢♦r t❤❡ ●❛✉ss✐❛♥ ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ✇✐t❤ ✇❡❛❦ ✐♥t❡r❢❡r❡♥❝❡❄✭❖P❊◆✮ ✭ ❨❊❙ ✿ ❝♦r♥❡r ♣♦✐♥ts ✉s✐♥❣ ✐❞❡❛s ✐♥ ♠❡❛s✉r❡ tr❛♥s♣♦rt❛t✐♦♥ ❜② P♦❧②❛♥s❦✐②✲❲✉ ✬✶✺✮ ✻✳✹ ■s t❤❡ ❍❛♥✲❑♦❜❛②❛s❤✐ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s❄ ✭ ◆❖ ✿ ◆❛✐r✲❳✐❛✲❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮ ✽✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r t❤❡ ❣❡♥❡r❛❧ ✸✲r❡❝❡✐✈❡r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ♦♥❡ ♠❡ss❛❣❡ t♦ ❛❧❧ t❤r❡❡ r❡❝❡✐✈❡rs ❛♥❞ ❛♥♦t❤❡r ♠❡ss❛❣❡ t♦ t✇♦ r❡❝❡✐✈❡rs❄ ✭ ◆❖ ✿ ◆❛✐r✲❨❛③❞❛♥♣❛♥❛❤ ✬✶✼✮ ✽✳✸ ❉♦❡s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ ❛❝❤✐❡✈❡ t❤❡ s✉♠✲❝❛♣❛❝✐t② ♦❢ t❤❡ ❜✐♥❛r② s❦❡✇✲s②♠♠❡tr✐❝ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ✭❖P❊◆✮ ✽✳✹ ■s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ t✐❣❤t ✐♥ ❣❡♥❡r❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s❄ ✭❖P❊◆✮ ✾✳✷ ❈❛♥ t❤❡ ❝♦♥✈❡rs❡ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ❜❡ ♣r♦✈❡❞ ❞✐r❡❝t❧② ❜② ♦♣t✐♠✐③✐♥❣ t❤❡ ◆❛✐r✲❊❧ ●❛♠❛❧ ♦✉t❡r ❜♦✉♥❞❄ ✭ ❨❊❙ ✿ ●❡♥❣✲◆❛✐r ✬✶✹✮ ✾✳✸ ❉♦❡s t❤❡ ▼❛rt♦♥ ✐♥♥❡r ❜♦✉♥❞ ❛❝❤✐❡✈❡ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ♦❢ t❤❡ ✷✲r❡❝❡✐✈❡r ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✇✐t❤ ❝♦♠♠♦♥ ♠❡ss❛❣❡❄ ✭ ❨❊❙ ✿ ●❡♥❣✲◆❛✐r ✬✶✹✮ ✶✺

  35. ❖✉t❧✐♥❡ • ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❊st❛❜❧✐s❤✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s r❡❣✐♦♥ ❢♦r ▼■▼❖ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ • ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧✿ ❙✉❜✲♦♣t✐♠❛❧✐t② ♦❢ t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ r❡❣✐♦♥ • ❋❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ⋆ ❘❡❧❛t✐♦♥ t♦ ♣r♦❜❧❡♠s ♦❢ ✐♥t❡r❡st ✐♥ ♦t❤❡r ✜❡❧❞s ⋆ ❯♥✐❢②✐♥❣ ♦❜s❡r✈❛t✐♦♥s ❛♥❞ s♦♠❡ ❝♦♥❥❡❝t✉r❡s ✶✻

  36. ▼■▼❖ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✿ ✇❤❡r❡ ❞❡♥♦t❡s t❤❡ ❛❞❞✐t✐✈❡ ♥♦✐s❡✳ ❱❡r② ✐♠♣♦rt❛♥t ❝❤❛♥♥❡❧ ❝❧❛ss ✐♥ ✇✐r❡❧❡ss ❝♦♠♠✉♥✐❝❛t✐♦♥ ▼♦❞❡❧s✿ ♠✉❧t✐✲❛♥t❡♥♥❛ tr❛♥s♠✐tt❡r✴r❡❝❡✐✈❡rs ✭❞♦✇♥❧✐♥❦✮ ▼■▼❖ ✭❱❡❝t♦r✮ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 ✶✼

  37. ▼■▼❖ ✭❱❡❝t♦r✮ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ Y n 1 M 0 , ˆ ˆ W a ( y 1 | x ) ❉❡❝♦❞❡r ✶ M 1 X n ( M 0 , M 1 , M 2 ) ❊♥❝♦❞❡r Y n 2 M 0 , ˜ ˜ W b ( y 2 | x ) ❉❡❝♦❞❡r ✷ M 2 ▼■▼❖ ●❛✉ss✐❛♥ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ✿ Y 1 = AX + Z Y 2 = BX + Z ✇❤❡r❡ Z ∼ N (0 , I ) ❞❡♥♦t❡s t❤❡ ❛❞❞✐t✐✈❡ ♥♦✐s❡✳ ❱❡r② ✐♠♣♦rt❛♥t ❝❤❛♥♥❡❧ ❝❧❛ss ✐♥ ✇✐r❡❧❡ss ❝♦♠♠✉♥✐❝❛t✐♦♥ ▼♦❞❡❧s✿ ♠✉❧t✐✲❛♥t❡♥♥❛ tr❛♥s♠✐tt❡r✴r❡❝❡✐✈❡rs ✭❞♦✇♥❧✐♥❦✮ ✶✼

  38. ●✐st ✿ ❙❤♦✇✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ❢♦r ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ❘❡♠❛r❦ ✿ ■❞❡❛s ❞♦ ♥♦t ❡①t❡♥❞ t♦ s❤♦✇ ♦♣t✐♠❛❧✐t② ✇❤❡♥ t❤❡r❡ ✐s ❝♦♠♠♦♥ ♠❡ss❛❣❡✱ ✐✳❡✳ ❖♣t✐♠❛❧✐t② ✐♥ ❣❡♥❡r❛❧ ✭●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹✮ ●✐st ✿ ❉❡✈❡❧♦♣ ❛ t❡❝❤♥✐q✉❡ ❢♦r ♣r♦✈✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ✭❢r♦♠ s✉❜✲❛❞❞✐t✐✈✐t②✮ ❊①♣❧❛✐♥ ♦✉r t❡❝❤♥✐q✉❡ ♦♥ ✭❢♦r s✐♠♣❧✐❝✐t②✮ ❍✐st♦r② ❖♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❜♦✉♥❞✱ R ( W a , W b ) ✱ ✇❛s ❡st❛❜❧✐s❤❡❞✿ • ❙❝❛❧❛r ❝❛s❡ ✭❇❡r❣♠❛♥s ✬✼✸✮ ✭❊♥tr♦♣② P♦✇❡r ■♥❡q✉❛❧✐t②✮ • ❘❡✈❡rs❡❧② ❞❡❣r❛❞❡❞ s❡tt✐♥❣ ✭P♦❧t②r❡✈ ✬✼✽✱ ❊❧ ●❛♠❛❧ ✬✽✶✮ • ❖♣t✐♠❛❧✐t② ♦♥ R 0 = 0 ✭❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✮ ⋆ ❇✉✐❧❞s ♦♥ ✐❞❡❛s ✐♥ P♦❧t②r❡✈ ⋆ ❚♦✉r ❞❡ ❢♦r❝❡ ✐♥ ♦♣t✐♠✐③❛t✐♦♥ ✶✽

  39. ❖♣t✐♠❛❧✐t② ✐♥ ❣❡♥❡r❛❧ ✭●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹✮ ●✐st ✿ ❉❡✈❡❧♦♣ ❛ t❡❝❤♥✐q✉❡ ❢♦r ♣r♦✈✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ✭❢r♦♠ s✉❜✲❛❞❞✐t✐✈✐t②✮ ❊①♣❧❛✐♥ ♦✉r t❡❝❤♥✐q✉❡ ♦♥ ✭❢♦r s✐♠♣❧✐❝✐t②✮ ❍✐st♦r② ❖♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❜♦✉♥❞✱ R ( W a , W b ) ✱ ✇❛s ❡st❛❜❧✐s❤❡❞✿ • ❙❝❛❧❛r ❝❛s❡ ✭❇❡r❣♠❛♥s ✬✼✸✮ ✭❊♥tr♦♣② P♦✇❡r ■♥❡q✉❛❧✐t②✮ • ❘❡✈❡rs❡❧② ❞❡❣r❛❞❡❞ s❡tt✐♥❣ ✭P♦❧t②r❡✈ ✬✼✽✱ ❊❧ ●❛♠❛❧ ✬✽✶✮ • ❖♣t✐♠❛❧✐t② ♦♥ R 0 = 0 ✭❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✮ ⋆ ❇✉✐❧❞s ♦♥ ✐❞❡❛s ✐♥ P♦❧t②r❡✈ ⋆ ❚♦✉r ❞❡ ❢♦r❝❡ ✐♥ ♦♣t✐♠✐③❛t✐♦♥ ⋆ ●✐st ✿ ❙❤♦✇✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ❢♦r ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ⋆ ❘❡♠❛r❦ ✿ ■❞❡❛s ❞♦ ♥♦t ❡①t❡♥❞ t♦ s❤♦✇ ♦♣t✐♠❛❧✐t② ✇❤❡♥ t❤❡r❡ ✐s ❝♦♠♠♦♥ ♠❡ss❛❣❡✱ ✐✳❡✳ R 0 � = 0 ✶✽

  40. ❊①♣❧❛✐♥ ♦✉r t❡❝❤♥✐q✉❡ ♦♥ ✭❢♦r s✐♠♣❧✐❝✐t②✮ ❍✐st♦r② ❖♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❜♦✉♥❞✱ R ( W a , W b ) ✱ ✇❛s ❡st❛❜❧✐s❤❡❞✿ • ❙❝❛❧❛r ❝❛s❡ ✭❇❡r❣♠❛♥s ✬✼✸✮ ✭❊♥tr♦♣② P♦✇❡r ■♥❡q✉❛❧✐t②✮ • ❘❡✈❡rs❡❧② ❞❡❣r❛❞❡❞ s❡tt✐♥❣ ✭P♦❧t②r❡✈ ✬✼✽✱ ❊❧ ●❛♠❛❧ ✬✽✶✮ • ❖♣t✐♠❛❧✐t② ♦♥ R 0 = 0 ✭❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✮ ⋆ ❇✉✐❧❞s ♦♥ ✐❞❡❛s ✐♥ P♦❧t②r❡✈ ⋆ ❚♦✉r ❞❡ ❢♦r❝❡ ✐♥ ♦♣t✐♠✐③❛t✐♦♥ ⋆ ●✐st ✿ ❙❤♦✇✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ❢♦r ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ⋆ ❘❡♠❛r❦ ✿ ■❞❡❛s ❞♦ ♥♦t ❡①t❡♥❞ t♦ s❤♦✇ ♦♣t✐♠❛❧✐t② ✇❤❡♥ t❤❡r❡ ✐s ❝♦♠♠♦♥ ♠❡ss❛❣❡✱ ✐✳❡✳ R 0 � = 0 • ❖♣t✐♠❛❧✐t② ✐♥ ❣❡♥❡r❛❧ ✭●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹✮ ⋆ ●✐st ✿ ❉❡✈❡❧♦♣ ❛ t❡❝❤♥✐q✉❡ ❢♦r ♣r♦✈✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ✭❢r♦♠ s✉❜✲❛❞❞✐t✐✈✐t②✮ ✶✽

  41. ❍✐st♦r② ❖♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❜♦✉♥❞✱ R ( W a , W b ) ✱ ✇❛s ❡st❛❜❧✐s❤❡❞✿ • ❙❝❛❧❛r ❝❛s❡ ✭❇❡r❣♠❛♥s ✬✼✸✮ ✭❊♥tr♦♣② P♦✇❡r ■♥❡q✉❛❧✐t②✮ • ❘❡✈❡rs❡❧② ❞❡❣r❛❞❡❞ s❡tt✐♥❣ ✭P♦❧t②r❡✈ ✬✼✽✱ ❊❧ ●❛♠❛❧ ✬✽✶✮ • ❖♣t✐♠❛❧✐t② ♦♥ R 0 = 0 ✭❲❡✐♥❣❛rt❡♥ ❛♥❞ ❙t❡✐♥❜❡r❣ ❛♥❞ ❙❤❛♠❛✐ ✬✵✻✮ ⋆ ❇✉✐❧❞s ♦♥ ✐❞❡❛s ✐♥ P♦❧t②r❡✈ ⋆ ❚♦✉r ❞❡ ❢♦r❝❡ ✐♥ ♦♣t✐♠✐③❛t✐♦♥ ⋆ ●✐st ✿ ❙❤♦✇✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ❢♦r ❛ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠ ⋆ ❘❡♠❛r❦ ✿ ■❞❡❛s ❞♦ ♥♦t ❡①t❡♥❞ t♦ s❤♦✇ ♦♣t✐♠❛❧✐t② ✇❤❡♥ t❤❡r❡ ✐s ❝♦♠♠♦♥ ♠❡ss❛❣❡✱ ✐✳❡✳ R 0 � = 0 • ❖♣t✐♠❛❧✐t② ✐♥ ❣❡♥❡r❛❧ ✭●❡♥❣ ❛♥❞ ◆❛✐r ✬✶✹✮ ⋆ ●✐st ✿ ❉❡✈❡❧♦♣ ❛ t❡❝❤♥✐q✉❡ ❢♦r ♣r♦✈✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ●❛✉ss✐❛♥ r❛♥❞♦♠ ✈❛r✐❛❜❧❡s ✭❢r♦♠ s✉❜✲❛❞❞✐t✐✈✐t②✮ ❊①♣❧❛✐♥ ♦✉r t❡❝❤♥✐q✉❡ ♦♥ R 0 = 0 ✭❢♦r s✐♠♣❧✐❝✐t②✮ ✶✽

  42. ✭◆❛✐r ✬✶✸✮ ✉♣♣❡r ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡✿ ◆♦t ❡❛s② t♦ ❝♦♠♣✉t❡ ✭✐♥ ❣❡♥❡r❛❧✮ ❋♦r ✱ ❧❡t ❖✉t❡r ❜♦✉♥❞ ✭❑♦r♥❡r✲▼❛rt♦♥ ✬✼✾✮ ❚❤❡ s❡t ♦❢ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) s❛t✐s❢②✐♥❣ R 2 ≤ I ( U ; Y 2 ) R 1 + R 2 ≤ I ( U ; Y 2 ) + I ( X ; Y 1 | U ) ❢♦r s♦♠❡ p ( u, x ) ✱ ✇❤❡r❡ E( � X � 2 ) ≤ P ❢♦r♠s ❛♥ ♦✉t❡r ❜♦✉♥❞ t♦ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥✳ ❉❡♥♦t❡ t❤✐s r❡❣✐♦♥ ❛s O ( W a , W b ) ✳ ✶✾

  43. ✭◆❛✐r ✬✶✸✮ ✉♣♣❡r ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡✿ ◆♦t ❡❛s② t♦ ❝♦♠♣✉t❡ ✭✐♥ ❣❡♥❡r❛❧✮ ❖✉t❡r ❜♦✉♥❞ ✭❑♦r♥❡r✲▼❛rt♦♥ ✬✼✾✮ ❚❤❡ s❡t ♦❢ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) s❛t✐s❢②✐♥❣ R 2 ≤ I ( U ; Y 2 ) R 1 + R 2 ≤ I ( U ; Y 2 ) + I ( X ; Y 1 | U ) ❢♦r s♦♠❡ p ( u, x ) ✱ ✇❤❡r❡ E( � X � 2 ) ≤ P ❢♦r♠s ❛♥ ♦✉t❡r ❜♦✉♥❞ t♦ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥✳ ❉❡♥♦t❡ t❤✐s r❡❣✐♦♥ ❛s O ( W a , W b ) ✳ ❋♦r λ > 1 ✱ ❧❡t S λ ( W a , W b ) := ( R 1 ,R 2 ) ∈O R 1 + λR 2 max = max p ( u,x ) λI ( U ; Y 2 ) + I ( X ; Y 1 | U ) ✶✾

  44. ✉♣♣❡r ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡✿ ◆♦t ❡❛s② t♦ ❝♦♠♣✉t❡ ✭✐♥ ❣❡♥❡r❛❧✮ ❖✉t❡r ❜♦✉♥❞ ✭❑♦r♥❡r✲▼❛rt♦♥ ✬✼✾✮ ❚❤❡ s❡t ♦❢ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) s❛t✐s❢②✐♥❣ R 2 ≤ I ( U ; Y 2 ) R 1 + R 2 ≤ I ( U ; Y 2 ) + I ( X ; Y 1 | U ) ❢♦r s♦♠❡ p ( u, x ) ✱ ✇❤❡r❡ E( � X � 2 ) ≤ P ❢♦r♠s ❛♥ ♦✉t❡r ❜♦✉♥❞ t♦ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥✳ ❉❡♥♦t❡ t❤✐s r❡❣✐♦♥ ❛s O ( W a , W b ) ✳ ❋♦r λ > 1 ✱ ❧❡t S λ ( W a , W b ) := ( R 1 ,R 2 ) ∈O R 1 + λR 2 max = max p ( u,x ) λI ( U ; Y 2 ) + I ( X ; Y 1 | U ) � � λI ( X ; Z ) + C µ X [ I ( X ; Y ) − λI ( X ; Z )] = max ✭◆❛✐r ✬✶✸✮ p ( x ) ✶✾

  45. ❖✉t❡r ❜♦✉♥❞ ✭❑♦r♥❡r✲▼❛rt♦♥ ✬✼✾✮ ❚❤❡ s❡t ♦❢ r❛t❡ ♣❛✐rs ( R 1 , R 2 ) s❛t✐s❢②✐♥❣ R 2 ≤ I ( U ; Y 2 ) R 1 + R 2 ≤ I ( U ; Y 2 ) + I ( X ; Y 1 | U ) ❢♦r s♦♠❡ p ( u, x ) ✱ ✇❤❡r❡ E( � X � 2 ) ≤ P ❢♦r♠s ❛♥ ♦✉t❡r ❜♦✉♥❞ t♦ t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥✳ ❉❡♥♦t❡ t❤✐s r❡❣✐♦♥ ❛s O ( W a , W b ) ✳ ❋♦r λ > 1 ✱ ❧❡t S λ ( W a , W b ) := ( R 1 ,R 2 ) ∈O R 1 + λR 2 max = max p ( u,x ) λI ( U ; Y 2 ) + I ( X ; Y 1 | U ) � � λI ( X ; Z ) + C µ X [ I ( X ; Y ) − λI ( X ; Z )] = max ✭◆❛✐r ✬✶✸✮ p ( x ) x x f ( x ) ✉♣♣❡r ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡✿ C x [ f ] ✶✾ ◆♦t ❡❛s② t♦ ❝♦♠♣✉t❡ ✭✐♥ ❣❡♥❡r❛❧✮

  46. ❖♥❡ ❝❛♥ s❤♦✇ t❤❛t ✐❢ ●❛✉ss✐❛♥s ♠❛①✐♠✐③❡ C µ X [ h ( Y 1 ) − λh ( Y 2 )] t❤❡♥ ▼❛rt♦♥✬s ✐♥♥❡r ❜♦✉♥❞ ✐s ♦♣t✐♠❛❧ ✭♦♥ R 0 = 0 ✮ ❍❡r❡ h ( X ) ✐s t❤❡ ❞✐✛❡r❡♥t✐❛❧ ❡♥tr♦♣②✿ � − h ( X ) := f ( x ) log f ( x ) dx, ✇❤❡r❡ f ( x ) ✐s t❤❡ ❞❡♥s✐t② ❢✉♥❝t✐♦♥ ♦❢ X ✳ ❆ s✐♠✐❧❛r ✭♠♦r❡✲✐♥✈♦❧✈❡❞✮ ♣r♦❜❧❡♠ s❤♦✇s ✉♣ ✇❤❡♥ R 0 � = 0 ❆♥ ✐❞❡♥t✐❝❛❧ t❡❝❤♥✐q✉❡ ✭t♦ t❤❡ ♦♥❡ ■ ❛♠ ❣♦✐♥❣ t♦ ❞❡♠♦♥str❛t❡✮ ❡st❛❜❧✐s❤❡s t❤❛t ❛❧s♦ ✷✵

  47. ▲❡♠♠❛ ✿ ✐s s✉❜✲❛❞❞✐t✐✈❡✳ Pr♦♦❢ ✿ ❋♦r ❛♥② ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ✈✐❛ s✉❜✲❛❞❞✐t✐✈✐t② ✭●❡♥❣✲◆❛✐r ✬✶✹✮ ▼❛①✐♠✐③❡✱ ❢♦r λ > 1 ✱ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❢✉♥❝t✐♦♥❛❧ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ♦✈❡r X : ❊ ( XX T ) � K ✱ ✇❤❡r❡ A, B ❛r❡ ✐♥✈❡rt✐❜❧❡ ♠❛tr✐❝❡s ❛♥❞ Z ∼ N (0 , I ) ✳ ❲❡ ✇✐❧❧ s❡❡ t❤❛t t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ✐s h ( AX ∗ + Z ) − λh ( BX ∗ + Z ) , ✇❤❡r❡ X ∗ ∼ N (0 , K ′ ) ❢♦r s♦♠❡ K ′ � K ✳ ✷✶

  48. ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ✈✐❛ s✉❜✲❛❞❞✐t✐✈✐t② ✭●❡♥❣✲◆❛✐r ✬✶✹✮ ▼❛①✐♠✐③❡✱ ❢♦r λ > 1 ✱ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❢✉♥❝t✐♦♥❛❧ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ♦✈❡r X : ❊ ( XX T ) � K ✱ ✇❤❡r❡ A, B ❛r❡ ✐♥✈❡rt✐❜❧❡ ♠❛tr✐❝❡s ❛♥❞ Z ∼ N (0 , I ) ✳ ❲❡ ✇✐❧❧ s❡❡ t❤❛t t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ✐s h ( AX ∗ + Z ) − λh ( BX ∗ + Z ) , ✇❤❡r❡ X ∗ ∼ N (0 , K ′ ) ❢♦r s♦♠❡ K ′ � K ✳ ▲❡♠♠❛ ✿ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ✐s s✉❜✲❛❞❞✐t✐✈❡✳ Pr♦♦❢ ✿ ❋♦r ❛♥② µ X 1 ,X 2 h ( AX 1 + Z 1 , AX 2 + Z 2 | U ) − λh ( BX 1 + Z 1 , BX 2 + Z 2 | U ) = h ( AX 1 + Z 1 | U, AX 2 + Z 2 ) − λh ( BX 1 + Z 1 | U, AX 2 + Z 2 ) + h ( AX 2 + Z 2 | U, BX 1 + Z 1 ) − λh ( BX 2 + Z 2 | U, BX 1 + Z 1 ) − ( λ − 1) I ( AX 2 + Z 2 ; BX 1 + Z 1 | U ) ✷✶

  49. ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ✈✐❛ s✉❜✲❛❞❞✐t✐✈✐t② ✭●❡♥❣✲◆❛✐r ✬✶✹✮ ▼❛①✐♠✐③❡✱ ❢♦r λ > 1 ✱ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❢✉♥❝t✐♦♥❛❧ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ♦✈❡r X : ❊ ( XX T ) � K ✱ ✇❤❡r❡ A, B ❛r❡ ✐♥✈❡rt✐❜❧❡ ♠❛tr✐❝❡s ❛♥❞ Z ∼ N (0 , I ) ✳ ❲❡ ✇✐❧❧ s❡❡ t❤❛t t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ✐s h ( AX ∗ + Z ) − λh ( BX ∗ + Z ) , ✇❤❡r❡ X ∗ ∼ N (0 , K ′ ) ❢♦r s♦♠❡ K ′ � K ✳ ▲❡♠♠❛ ✿ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ✐s s✉❜✲❛❞❞✐t✐✈❡✳ Pr♦♦❢ ✿ ❋♦r ❛♥② µ X 1 ,X 2 C µ X 1 ,X 2 [ h ( AX 1 + Z 1 , AX 2 + Z 2 ) − λh ( BX 1 + Z 1 , BX 2 + Z 2 )] ≤ C µ X 1 [ h ( AX 1 + Z 1 ) − λh ( BX 1 + Z 1 )] + C µ X 2 [ h ( AX 2 + Z 2 ) − λh ( BX 2 + Z 2 )] ✷✶

  50. ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ✈✐❛ s✉❜✲❛❞❞✐t✐✈✐t② ✭●❡♥❣✲◆❛✐r ✬✶✹✮ ▼❛①✐♠✐③❡✱ ❢♦r λ > 1 ✱ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❢✉♥❝t✐♦♥❛❧ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ♦✈❡r X : ❊ ( XX T ) � K ✱ ✇❤❡r❡ A, B ❛r❡ ✐♥✈❡rt✐❜❧❡ ♠❛tr✐❝❡s ❛♥❞ Z ∼ N (0 , I ) ✳ ❲❡ ✇✐❧❧ s❡❡ t❤❛t t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ✐s h ( AX ∗ + Z ) − λh ( BX ∗ + Z ) , ✇❤❡r❡ X ∗ ∼ N (0 , K ′ ) ❢♦r s♦♠❡ K ′ � K ✳ ▲❡♠♠❛ ✿ C µ X [ h ( AX + Z ) − λh ( BX + Z )] ✐s s✉❜✲❛❞❞✐t✐✈❡✳ Pr♦♦❢ ✿ ❋♦r ❛♥② µ X 1 ,X 2 h ( AX 1 + Z 1 , AX 2 + Z 2 | U ) − λh ( BX 1 + Z 1 , BX 2 + Z 2 | U ) = h ( AX 1 + Z 1 | U, AX 2 + Z 2 ) − λh ( BX 1 + Z 1 | U, AX 2 + Z 2 ) + h ( AX 2 + Z 2 | U, BX 1 + Z 1 ) − λh ( BX 2 + Z 2 | U, BX 1 + Z 1 ) − ( λ − 1) I ( AX 2 + Z 2 ; BX 1 + Z 1 | U ) ✷✶

  51. ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ❛r❡ ●❛✉ss✐❛♥ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ✷✷

  52. ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ❛r❡ ●❛✉ss✐❛♥ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ❚❤❡r❡❢♦r❡ ✿ ✇❡ ❣❡t t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ✳ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ❙❡tt✐♥❣ U = ( U a , U b ) ✱ X + = X a + X b ❛♥❞ X − = X a − X b t❤❡ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t② √ √ 2 2 ②✐❡❧❞s � � 2 V = C µ X 1 ,X 2 [ h ( AX 1 + Z 1 , AX 2 + Z 2 ) − λh ( BX 1 + Z 1 , BX 2 + Z 2 )] � ( µ X + ,X − ) � � ≤ C µ X 1 [ h ( AX 1 + Z 1 ) − λh ( BX 1 + Z 1 )] � µ X + � � + C µ X 2 [ h ( AX 2 + Z 2 ) − λh ( BX 2 + Z 2 )] � µ X − − ( λ − 1) I ( AX − + Z 2 ; BX + + Z 1 | U a , U b ) ≤ V + V ✷✷

  53. ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ❛r❡ ●❛✉ss✐❛♥ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ❙❡tt✐♥❣ U = ( U a , U b ) ✱ X + = X a + X b ❛♥❞ X − = X a − X b t❤❡ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t② √ √ 2 2 ②✐❡❧❞s � � 2 V = C µ X 1 ,X 2 [ h ( AX 1 + Z 1 , AX 2 + Z 2 ) − λh ( BX 1 + Z 1 , BX 2 + Z 2 )] � ( µ X + ,X − ) � � ≤ C µ X 1 [ h ( AX 1 + Z 1 ) − λh ( BX 1 + Z 1 )] � µ X + � � + C µ X 2 [ h ( AX 2 + Z 2 ) − λh ( BX 2 + Z 2 )] � µ X − − ( λ − 1) I ( AX − + Z 2 ; BX + + Z 1 | U a , U b ) ≤ V + V ❚❤❡r❡❢♦r❡ ✿ ✇❡ ❣❡t t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ X + ⊥ X − ✳ ✷✷

  54. ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ✿ ❛r❡ ●❛✉ss✐❛♥ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ • X a ⊥ X b ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ • ( X a + X b ) ⊥ ( X a − X b ) ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ ✷✷

  55. ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ • X a ⊥ X b ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ • ( X a + X b ) ⊥ ( X a − X b ) ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ • ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ X a , X b ❛r❡ ●❛✉ss✐❛♥ ⋆ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ ⋆ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ✷✷

  56. ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t②✿ ❝t❞✳✳ ▲❡t ( U † , X † ) ❜❡ ❛ ♠❛①✐♠✐③❡r✱ ✐✳❡✳ V = max µ X C µ X [ h ( AX + Z ) − λh ( BX + Z )] = h ( AX † + Z | U † ) − λh ( BX † + Z | U † ) . ▲❡t ( X a , U a ) ❛♥❞ ( X b , U b ) ❜❡ ✐✳✐✳❞✳ ❛❝❝♦r❞✐♥❣ t♦ ( U † , X † ) ✳ ◆♦t❡ ✿ ❚❤✉s✱ ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ • X a ⊥ X b ✭❢r♦♠ ❝♦♥str✉❝t✐♦♥✮ • ( X a + X b ) ⊥ ( X a − X b ) ✭❢r♦♠ ♣r♦♦❢ ♦❢ s✉❜✲❛❞❞✐t✐✈✐t②✮ • ■♠♣❧✐❡s t❤❛t ❝♦♥❞✐t✐♦♥❡❞ ♦♥ ( U a , U b ) ✿ X a , X b ❛r❡ ●❛✉ss✐❛♥ ⋆ ❈❤❛r❛❝t❡r✐③❛t✐♦♥ ♦❢ ●❛✉ss✐❛♥s ✭❇❡r♥st❡✐♥ ✬✹✵s✮ ⋆ Pr♦♦❢✿ ❯s✐♥❣ ❝❤❛r❛❝t❡r✐st✐❝ ❢✉♥❝t✐♦♥s ✭❋♦✉r✐❡r tr❛♥s❢♦r♠s✮ ❚❤✐s t❡❝❤♥✐q✉❡ ❤❛s ❜❡❡♥ s✉❜s❡q✉❡♥t❧② ✉s❡❞ ❜② ♦t❤❡rs ✐♥ ✈❛r✐♦✉s ♦t❤❡r ✐♥st❛♥❝❡s✳ ◆♦t❡ ✿ ❚❤❡r❡ ❛r❡ s♦♠❡ s✐♠✐❧❛r✐t✐❡s ✇✐t❤ ✇♦r❦ ♦❢ ▲✐❡❜ ❛♥❞ ❇❛rt❤❡ ✭✾✵s✮ ❚❤❡② ❛❧s♦ ✉s❡ r♦t❛t✐♦♥s ✭❜✉t ♥♦t ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ ✐ts ❛❧❣❡❜r❛✮ ✷✷

  57. ❆✣r♠❛t✐✈❡ ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡❄ ❲❤② s❤♦✉❧❞ s♦♠❡♦♥❡ ❝❛r❡❄ ■❢ tr✉❡✱ s♦❧✈❡s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❩✲✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ❘❡❧❛t❡❞ t♦ r❡✈❡rs❡ ❊P■s✱ ❤②♣❡r♣❧❛♥❡ ❝♦♥❥❡❝t✉r❡✱ ❡t❝✳ ❆♥ ♦♣❡♥ q✉❡st✐♦♥ ❲❡ ❤❛✈❡ s❡❡♥ ✭②❡st❡r❞❛② ❛♥❞ t♦❞❛②✮ ❤♦✇ s✉❜✲❛❞❞✐t✐✈✐t② ✐♠♣❧✐❡s ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ❖♣❡♥ q✉❡st✐♦♥ ❋♦r α, a ∈ (0 , 1) ✱ ❞♦ ●❛✉ss✐❛♥s ♠❛①✐♠✐③❡ t❤❡ ❢✉♥❝t✐♦♥❛❧ αh ( X 2 + aX 1 + Z ) + (1 − α ) h ( X 1 + Z ) − h ( aX 1 + Z ) ♦✈❡r X 1 ⊥ X 2 ✱ s✉❜❥❡❝t t♦ E( X 2 1 ) ≤ P 1 ✱ E( X 2 2 ) ≤ P 2 ✳ ❍❡r❡ Z ∼ N (0 , 1) ✐s ✐♥❞❡♣❡♥❞❡♥t ♦❢ X 1 , X 2 ✳ ✷✸

  58. ❲❤② s❤♦✉❧❞ s♦♠❡♦♥❡ ❝❛r❡❄ ■❢ tr✉❡✱ s♦❧✈❡s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❩✲✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ❘❡❧❛t❡❞ t♦ r❡✈❡rs❡ ❊P■s✱ ❤②♣❡r♣❧❛♥❡ ❝♦♥❥❡❝t✉r❡✱ ❡t❝✳ ❆♥ ♦♣❡♥ q✉❡st✐♦♥ ❲❡ ❤❛✈❡ s❡❡♥ ✭②❡st❡r❞❛② ❛♥❞ t♦❞❛②✮ ❤♦✇ s✉❜✲❛❞❞✐t✐✈✐t② ✐♠♣❧✐❡s ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ❖♣❡♥ q✉❡st✐♦♥ ❋♦r α, a ∈ (0 , 1) ✱ ❞♦ ●❛✉ss✐❛♥s ♠❛①✐♠✐③❡ t❤❡ ❢✉♥❝t✐♦♥❛❧ αh ( X 2 + aX 1 + Z ) + (1 − α ) h ( X 1 + Z ) − h ( aX 1 + Z ) ♦✈❡r X 1 ⊥ X 2 ✱ s✉❜❥❡❝t t♦ E( X 2 1 ) ≤ P 1 ✱ E( X 2 2 ) ≤ P 2 ✳ ❍❡r❡ Z ∼ N (0 , 1) ✐s ✐♥❞❡♣❡♥❞❡♥t ♦❢ X 1 , X 2 ✳ ❆✣r♠❛t✐✈❡ ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡❄ � � C µ X 1 αh ( X 2 + aX 1 + Z ) + (1 − α ) h ( X 1 + Z ) − h ( aX 1 + Z ) ✷✸

  59. ❆♥ ♦♣❡♥ q✉❡st✐♦♥ ❲❡ ❤❛✈❡ s❡❡♥ ✭②❡st❡r❞❛② ❛♥❞ t♦❞❛②✮ ❤♦✇ s✉❜✲❛❞❞✐t✐✈✐t② ✐♠♣❧✐❡s ●❛✉ss✐❛♥ ♦♣t✐♠❛❧✐t② ❖♣❡♥ q✉❡st✐♦♥ ❋♦r α, a ∈ (0 , 1) ✱ ❞♦ ●❛✉ss✐❛♥s ♠❛①✐♠✐③❡ t❤❡ ❢✉♥❝t✐♦♥❛❧ αh ( X 2 + aX 1 + Z ) + (1 − α ) h ( X 1 + Z ) − h ( aX 1 + Z ) ♦✈❡r X 1 ⊥ X 2 ✱ s✉❜❥❡❝t t♦ E( X 2 1 ) ≤ P 1 ✱ E( X 2 2 ) ≤ P 2 ✳ ❍❡r❡ Z ∼ N (0 , 1) ✐s ✐♥❞❡♣❡♥❞❡♥t ♦❢ X 1 , X 2 ✳ ❆✣r♠❛t✐✈❡ ✐❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡❄ � � C µ X 1 αh ( X 2 + aX 1 + Z ) + (1 − α ) h ( X 1 + Z ) − h ( aX 1 + Z ) ❲❤② s❤♦✉❧❞ s♦♠❡♦♥❡ ❝❛r❡❄ • ■❢ tr✉❡✱ s♦❧✈❡s t❤❡ ❝❛♣❛❝✐t② r❡❣✐♦♥ ❢♦r t❤❡ ●❛✉ss✐❛♥ ❩✲✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ • ❘❡❧❛t❡❞ t♦ r❡✈❡rs❡ ❊P■s✱ ❤②♣❡r♣❧❛♥❡ ❝♦♥❥❡❝t✉r❡✱ ❡t❝✳ ✷✸

  60. ❖✉t❧✐♥❡ • ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❊st❛❜❧✐s❤✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❢♦r ▼■▼❖ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ • ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧✿ ❙✉❜✲♦♣t✐♠❛❧✐t② ♦❢ t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ r❡❣✐♦♥ • ❋❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ⋆ ❘❡❧❛t✐♦♥ t♦ ♣r♦❜❧❡♠s ♦❢ ✐♥t❡r❡st ✐♥ ♦t❤❡r ✜❡❧❞s ⋆ ❯♥✐❢②✐♥❣ ♦❜s❡r✈❛t✐♦♥s ❛♥❞ s♦♠❡ ❝♦♥❥❡❝t✉r❡s ✷✹

  61. ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❆❤❧s✇❡❞❡ ✬✼✹✮ X n Y n 1 1 W a ( y 1 | x 1 , x 2 ) ˆ M 1 ❊♥❝♦❞❡r ✶ ❉❡❝♦❞❡r ✶ M 1 Y n 2 ˆ W b ( y 2 | x 1 , x 2 ) M 2 ❊♥❝♦❞❡r ✷ ❉❡❝♦❞❡r ✷ M 2 X n 2 ✷✺

  62. ❋✐rst st❡♣✿ ❋✐♥❞ ❛ ❝❤❛♥♥❡❧ ❝❧❛ss ✇❤❡r❡ ❍❑ r❡❣✐♦♥ s✐♠♣❧✐✜❡s ❆◆❉ ②❡t ♥♦t t♦♦ tr✐✈✐❛❧ ❍❛♥✲❑♦❜❛②❛s❤✐ ❛❝❤✐❡✈❛❜❧❡ r❡❣✐♦♥ ✭✶✾✽✶✮ á ❧❛ ❈❤♦♥❣ ❡t✳ ❛❧✳ ❆ r❛t❡✲♣❛✐r ( R 1 , R 2 ) ✐s ❛❝❤✐❡✈❛❜❧❡ ❢♦r t❤❡ ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ✐❢ R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < I ( X 2 ; Y 2 | U 1 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | U 1 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , 2 R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , R 1 + 2 R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) + I ( X 1 , U 2 ; Y 1 | U 1 , Q ) ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( u 1 , x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 1 | ≤ | X 1 | + 4 ✱ | U 2 | ≤ | X 2 | + 4 ✱ ❛♥❞ | Q | ≤ 7 ✳ ❉❡♥♦t❡ t❤❡ ✭❝❧♦s✉r❡ ♦❢✮ r❡❣✐♦♥ ❛s R ( W a , W b ) ✳ ◆✉♠❡r✐❝❛❧❧② ✐♥❢❡❛s✐❜❧❡ t♦ ❝♦♠♣✉t❡ R ( W a W b ) ❡✈❡♥ ❢♦r ❣❡♥❡r✐❝ ❜✐♥❛r②✲✐♥♣✉t ❜✐♥❛r②✲♦✉t♣✉t ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s ✷✻

  63. ❍❛♥✲❑♦❜❛②❛s❤✐ ❛❝❤✐❡✈❛❜❧❡ r❡❣✐♦♥ ✭✶✾✽✶✮ á ❧❛ ❈❤♦♥❣ ❡t✳ ❛❧✳ ❆ r❛t❡✲♣❛✐r ( R 1 , R 2 ) ✐s ❛❝❤✐❡✈❛❜❧❡ ❢♦r t❤❡ ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ✐❢ R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < I ( X 2 ; Y 2 | U 1 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | U 1 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , 2 R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + I ( X 1 ; Y 1 | U 1 , U 2 , Q ) + I ( X 2 , U 1 ; Y 2 | U 2 , Q ) , R 1 + 2 R 2 < I ( X 2 , U 1 ; Y 2 | Q ) + I ( X 2 ; Y 2 | U 1 , U 2 , Q ) + I ( X 1 , U 2 ; Y 1 | U 1 , Q ) ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( u 1 , x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 1 | ≤ | X 1 | + 4 ✱ | U 2 | ≤ | X 2 | + 4 ✱ ❛♥❞ | Q | ≤ 7 ✳ ❉❡♥♦t❡ t❤❡ ✭❝❧♦s✉r❡ ♦❢✮ r❡❣✐♦♥ ❛s R ( W a , W b ) ✳ ◆✉♠❡r✐❝❛❧❧② ✐♥❢❡❛s✐❜❧❡ t♦ ❝♦♠♣✉t❡ R ( W a W b ) ❡✈❡♥ ❢♦r ❣❡♥❡r✐❝ ❜✐♥❛r②✲✐♥♣✉t ❜✐♥❛r②✲♦✉t♣✉t ✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧s ❋✐rst st❡♣✿ • ❋✐♥❞ ❛ ❝❤❛♥♥❡❧ ❝❧❛ss ✇❤❡r❡ ❍❑ r❡❣✐♦♥ s✐♠♣❧✐✜❡s ❆◆❉ ②❡t ♥♦t t♦♦ tr✐✈✐❛❧ ✷✻

  64. ❈❧❡❛♥ ❩ ■♥t❡r❢❡r❡♥❝❡ ❈❤❛♥♥❡❧ ✭❈❩■❈✮ ▼♦❞❡❧ X n Y n 1 1 ˆ M 1 W a ( y 1 | x 1 , x 2 ) ❊♥❝♦❞❡r ✶ ❉❡❝♦❞❡r ✶ M 1 Y n 2 = X n 2 ˆ M 2 ❊♥❝♦❞❡r ✷ ❉❡❝♦❞❡r ✷ M 2 X n 2 ❈❧❡❛♥ ❩✲✐♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧ ▲❡♠♠❛ ✿ ❆ r❛t❡✲♣❛✐r ( R 1 , R 2 ) ❜❡❧♦♥❣s t♦ ❍❛♥✲❑♦❜❛②❛s❤✐ r❡❣✐♦♥ ✐❢ ❛♥❞ ♦♥❧② ✐❢ R 1 < I ( X 1 ; Y 1 | U 2 , Q ) , R 2 < H ( X 2 | Q ) , R 1 + R 2 < I ( X 1 , U 2 ; Y 1 | Q ) + H ( X 2 | U 2 , Q ) , ❢♦r s♦♠❡ ♣♠❢ p ( q ) p ( x 1 | q ) p ( u 2 , x 2 | q ) ✱ ✇❤❡r❡ | U 2 | ≤ | X 2 | ❛♥❞ | Q | ≤ 2 ✳ ❉❡♥♦t❡ r❡❣✐♦♥✿ R ( W a ) ✷✼

  65. ▲❡♠♠❛ ✭s✉❜✲❛❞❞✐t✐✈✐t②✮ ✭◆❛✐r✲❳✐❛✲❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮✿ ■♠♣❧✐❡s ♦♣t✐♠❛❧✐t② ♦❢ ✱ ✳ ❋♦r ✱ ✐s ❣✐✈❡♥ ❜② ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❊q✉✐✈❛❧❡♥t t♦ t❡st ✐❢ S λ ( W a ⊗ W a ) = 2 S λ ( W a ) , ∀ W a , λ ≥ 0 , ✇❤❡r❡ S λ ( W a ) := ( R 1 ,R 2 ) ∈R ( W a ) λR 1 + R 2 . max ✷✽

  66. ▲❡♠♠❛ ✭s✉❜✲❛❞❞✐t✐✈✐t②✮ ✭◆❛✐r✲❳✐❛✲❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮✿ ■♠♣❧✐❡s ♦♣t✐♠❛❧✐t② ♦❢ ✱ ✳ ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❊q✉✐✈❛❧❡♥t t♦ t❡st ✐❢ S λ ( W a ⊗ W a ) = 2 S λ ( W a ) , ∀ W a , λ ≥ 0 , ✇❤❡r❡ S λ ( W a ) := ( R 1 ,R 2 ) ∈R ( W a ) λR 1 + R 2 . max ❋♦r λ ∈ [0 , 1] ✱ S λ ( W a ) ✐s ❣✐✈❡♥ ❜② � � (1 − λ ) H ( X 2 ) + λI ( X 1 , U 2 ; Y 1 ) + λH ( X 2 | U 2 ) max p 1 ( x 1 ) p 2 ( u 2 ,x 2 ) � � = max H ( X 2 ) + λI ( X 1 ; Y 1 ) p 1 ( x 1 ) p 2 ( x 2 ) ✷✽

  67. ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ❊q✉✐✈❛❧❡♥t t♦ t❡st ✐❢ S λ ( W a ⊗ W a ) = 2 S λ ( W a ) , ∀ W a , λ ≥ 0 , ✇❤❡r❡ S λ ( W a ) := ( R 1 ,R 2 ) ∈R ( W a ) λR 1 + R 2 . max ❋♦r λ ∈ [0 , 1] ✱ S λ ( W a ) ✐s ❣✐✈❡♥ ❜② � � (1 − λ ) H ( X 2 ) + λI ( X 1 , U 2 ; Y 1 ) + λH ( X 2 | U 2 ) max p 1 ( x 1 ) p 2 ( u 2 ,x 2 ) � � = max H ( X 2 ) + λI ( X 1 ; Y 1 ) p 1 ( x 1 ) p 2 ( x 2 ) ▲❡♠♠❛ ✭s✉❜✲❛❞❞✐t✐✈✐t②✮ ✭◆❛✐r✲❳✐❛✲❨❛③❞❛♥♣❛♥❛❤ ✬✶✺✮✿ H ( X 21 , X 22 ) + λI ( X 11 , X 12 ; Y 11 , Y 12 ) � � � � ≤ H ( X 21 ) + λI ( X 11 ; Y 11 ) + H ( X 22 ) + λI ( X 12 ; Y 12 ) − (1 − λ ) I ( X 21 ; X 22 ) . ■♠♣❧✐❡s ♦♣t✐♠❛❧✐t② ♦❢ S λ ( W a ) ✱ λ ∈ [0 , 1] ✳ ✷✽

  68. ◗✉❡st✐♦♥ ✿ ❈❛♥ ✇❡ ♥✉♠❡r✐❝❛❧❧② t❡st ✐❢ ❄ ✐s ❛ ❜✐♥❛r② r❛♥❞♦♠ ✈❛r✐❛❜❧❡ ✭✐✳❡✳ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ♦✈❡r s✐♥❣❧❡ ✈❛r✐❛❜❧❡✮ ✿ ❤❛s ❛t ♠♦st ✷ ✐♥✢❡①✐♦♥ ♣♦✐♥ts ❲❤❛t ❛❜♦✉t λ > 1 ❄ ❋♦r λ ≥ 1 ✱ S λ ( W a ) ✐s ❣✐✈❡♥ ❜② � � I ( X 1 , U 2 ; Y 1 ) + H ( X 2 | U 2 ) + ( λ − 1) I ( X 1 ; Y 1 | U 2 ) max p 1 ( x 1 ) p 2 ( u 2 ,x 2 ) � � I ( X 1 , X 2 ; Y 1 ) + C X 2 [( λ − 1) I ( X 1 ; Y 1 ) + H ( X 2 ) − I ( X 2 ; Y 1 | X 1 )] = max p 1 ( x 1 ) p 2 ( x 2 ) ✷✾

  69. ❲❤❛t ❛❜♦✉t λ > 1 ❄ ❋♦r λ ≥ 1 ✱ S λ ( W a ) ✐s ❣✐✈❡♥ ❜② � � I ( X 1 , U 2 ; Y 1 ) + H ( X 2 | U 2 ) + ( λ − 1) I ( X 1 ; Y 1 | U 2 ) max p 1 ( x 1 ) p 2 ( u 2 ,x 2 ) � � I ( X 1 , X 2 ; Y 1 ) + C X 2 [( λ − 1) I ( X 1 ; Y 1 ) + H ( X 2 ) − I ( X 2 ; Y 1 | X 1 )] = max p 1 ( x 1 ) p 2 ( x 2 ) ◗✉❡st✐♦♥ ✿ ❈❛♥ ✇❡ ♥✉♠❡r✐❝❛❧❧② t❡st ✐❢ S λ ( W a ⊗ W a ) = 2 S λ ( W a ) ❄ X 2 ✐s ❛ ❜✐♥❛r② r❛♥❞♦♠ ✈❛r✐❛❜❧❡ ✭✐✳❡✳ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ♦✈❡r s✐♥❣❧❡ ✈❛r✐❛❜❧❡✮ ( λ − 1) I ( X 1 ; Y 1 ) + H ( X 2 ) − I ( X 2 ; Y 1 | X 1 ) ✿ ❤❛s ❛t ♠♦st ✷ ✐♥✢❡①✐♦♥ ♣♦✐♥ts ✷✾

  70. ❲❤❛t ❛❜♦✉t λ > 1 ❄ H ( X 2 ) + ( λ − 1) H ( Y 1 ) − λH ( Y 1 | X 1 ) P 2 ( X 2 ) [ H ( X 2 ) + ( λ − 1) H ( Y 1 ) − λH ( Y 1 | X 1 )] C P ( X 2 ) ❚❤❡ s❤❛♣❡ ♦❢ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ❢♦r ❛ ❣❡♥❡r✐❝ ❜✐♥❛r② ❈❩■❈ ✷✾

  71. ❙✉❜✲♦♣t✐♠❛❧✐t② ♦❢ t❤❡ ❍❛♥✲❑♦❜❛②❛s❤✐ r❡❣✐♦♥ A ❍❑ 1 2 A ❚■◆ ( W ⊗ 2 ) W ( Y 1 = 0 | X 1 , X 2 ) λ ( W ) λ λ � 1 � 0 . 5 ✷ ✶✳✶✵✼✺✶✻ ✶✳✶✵✽✶✹✶ 1 0 � 0 . 12 � 0 . 89 ✾ ✶✳✵✼✹✹✽✹ ✶✳✵✼✺✺✹✹ 0 . 21 0 . 62 � 0 . 01 � 0 . 58 ✶✷ ✶✳✷✽✾✽✸✵ ✶✳✷✾✸✼✻✵ 0 . 20 0 . 74 � 0 . 78 � 0 . 07 ✶✹ ✶✳✹✷✻✺✷✻ ✶✳✹✸✷✹✶✾ 0 . 46 0 . 05 � 0 . 91 � 0 . 22 ✶✺ ✶✳✸✷✸✼✻✻ ✶✳✸✸✾✵✻✺ 0 . 66 0 . 15 � 0 . 91 � 0 . 13 ✶✻ ✶✳✺✶✺✹✷✶ ✶✳✺✸✹✼✷✹ 0 . 62 0 . 06 � 0 . 38 � 0 . 87 ✶✽ ✶✳✹✹✾✾✺✾ ✶✳✹✻✽✺✼✼ 0 . 12 0 . 79 ❈♦✉♥t❡r❡①❛♠♣❧❡s t♦ t❤❡ ♦♣t✐♠❛❧✐t② ♦❢ ❍❛♥✲❑♦❜❛②❛s❤✐ r❡❣✐♦♥✳ ◆♦t❡ ✿ ❋♦r t❤❡ ✜rst ❡①❛♠♣❧❡✱ ✇❡ ❝❛♥ ❝❛❧❝✉❧❛t❡ t❤❡ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ❛♥❛❧②t✐❝❛❧❧②✳ ✸✵

  72. ▲❡t ❛♥❞ r❡s♣❡❝t✐✈❡❧② ❞❡♥♦t❡ ❛♥❞ ✇❤❡r❡ ✐s t❤❡ ❜✐♥❛r② ❡♥tr♦♣② ❢✉♥❝t✐♦♥ P❛rt✐❝✉❧❛r ❈❤❛♥♥❡❧ 1 2 0 0 0 0 X 1 Y 1 X 1 Y 1 1 2 1 1 1 1 X 2 = 0 X 2 = 1 • ❲❡ ❝♦♠♣✉t❡ max HK λR 1 + R 2 ❢♦r λ = 2 � �� � max H ( Y 1 ) + H ( X 2 ) + 2 H ( Y 1 ) − H ( Y 1 | X 1 ) C p 1 ( x 1 ) p 2 ( x 2 ) p 2 ( x 2 ) ✸✶

  73. P❛rt✐❝✉❧❛r ❈❤❛♥♥❡❧ 1 2 0 0 0 0 X 1 Y 1 X 1 Y 1 1 2 1 1 1 1 X 2 = 0 X 2 = 1 • ❲❡ ❝♦♠♣✉t❡ max HK λR 1 + R 2 ❢♦r λ = 2 f ( p, q ) � �� � max H ( Y 1 ) + H ( X 2 ) + 2 H ( Y 1 ) − H ( Y 1 | X 1 ) C p 1 ( x 1 ) p 2 ( x 2 ) p 2 ( x 2 ) • ▲❡t p ❛♥❞ q r❡s♣❡❝t✐✈❡❧② ❞❡♥♦t❡ Pr ( X 1 = 0) ❛♥❞ Pr ( X 2 = 0) q ) − 2 ph b ( q + 1 p ) h b ( q ) + h b ( q + p f ( p, q ) = (1 − 2¯ 2 ¯ ) 2 ✇❤❡r❡ h b ( . ) ✐s t❤❡ ❜✐♥❛r② ❡♥tr♦♣② ❢✉♥❝t✐♦♥ ✸✶

  74. P❛rt✐❝✉❧❛r ❝❤❛♥♥❡❧ ❝♦♥t✐♥✉❡❞ f ( p, q ) ✐s ❝♦♥❝❛✈❡ ✐♥ q ❢♦r p ≥ 1 2 ❛♥❞ ❢♦r 0 ≤ p < 1 2  f ( p, q ) q > 1 − 2 p  q [ f ( p, q )] = C f ( p, 1 − 2 p ) − f ( p, 0) q + f ( p, 0) q ∈ [0 , 1 − 2 p ]  1 − 2 p ✸✷

  75. P❛rt✐❝✉❧❛r ❝❤❛♥♥❡❧ ❝♦♥t✐♥✉❡❞ f ( p, q ) ✐s ❝♦♥❝❛✈❡ ✐♥ q ❢♦r p ≥ 1 2 ❛♥❞ ❢♦r 0 ≤ p < 1 2  f ( p, q ) q > 1 − 2 p  q [ f ( p, q )] = C f ( p, 1 − 2 p ) − f ( p, 0) q + f ( p, 0) q ∈ [0 , 1 − 2 p ]  1 − 2 p ✵✳✸ ✵✳✷✺ ✵✳✷ ✵✳✶✺ ✵✳✶ f (0 . 2 , q ) ✵✳✵✺ C q [ f (0 . 2 , q )] q ✵ 0 0 . 1 0 . 2 0 . 3 0 . 4 0 . 5 0 . 6 0 . 7 0 . 8 0 . 9 1 ✸✷

  76. P❛rt✐❝✉❧❛r ❝❤❛♥♥❡❧ ❝♦♥t✐♥✉❡❞ f ( p, q ) ✐s ❝♦♥❝❛✈❡ ✐♥ q ❢♦r p ≥ 1 2 ❛♥❞ ❢♦r 0 ≤ p < 1 2  f ( p, q ) q > 1 − 2 p  q [ f ( p, q )] = C f ( p, 1 − 2 p ) − f ( p, 0) q + f ( p, 0) q ∈ [0 , 1 − 2 p ]  1 − 2 p ❈♦r♦❧❧❛r② ▼❛①✐♠✉♠ ♦❢ 2 R 1 + R 2 ❢♦r t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ r❡❣✐♦♥ ✐s ❡q✉❛❧ t♦ t❤❡ ♠❛①✐♠✉♠ ♦❢ T ( p, q ) ❢♦r ( p, q ) ∈ [0 , 1] × [0 , 1] ✱ ✇❤❡r❡  h b ( q + p 2 ¯ q ) + f ( p, q ) q ≥ min { 0 , 1 − 2 p }  T ( p, q ) = q ) + f ( p, 1 − 2 p ) − f ( p, 0) h b ( q + p 2 ¯ q + f ( p, 0) o.w.,  1 − 2 p q ) − 2 ph b ( q +1 p ) h b ( q ) + h b ( q + p ✇❤❡r❡ f ( p, q ) = (1 − 2¯ 2 ¯ 2 ) ✸✷

  77. P❧♦t ♦❢ T ( p, q ) ◆✉♠❡r✐❝❛❧ s❡❛r❝❤ ✐♥❞✐❝❛t❡s✿ max p,q T ( p, q ) = 1 . 107516 .. ❛t p = 0 . 5078 .. ❛♥❞ q = 0 . 4365 .. ✸✸

  78. P❛rt✐❝✉❧❛r ❝❤❛♥♥❡❧ ❝♦♥t✐♥✉❡❞ • ■♥t❡r✈❛❧ ❛r✐t❤♠❡t✐❝ ✐s ❛ ♠❡t❤♦❞ t♦ ♦❜t❛✐♥ ❢♦r♠❛❧ ❜♦✉♥❞s ❢♦r ❢✉♥❝t✐♦♥s ❝♦♥s✐st✐♥❣ ♦❢ ❜❛s✐❝ ❛r✐t❤♠❡t✐❝ ❢✉♥❝t✐♦♥s ❛♥❞ ❝♦♠♠♦♥❧② ✉s❡❞ ❢✉♥❝t✐♦♥s s✉❝❤ ❛s ❧♦❣❛r✐t❤♠s ❛♥❞ tr✐❣♦♥♦♠❡tr✐❝ ❢✉♥❝t✐♦♥s✳ • T ( p, q ) ♦♥❧② ✐♥❝❧✉❞❡s ❜❛s✐❝ ❛r✐t❤♠❡t✐❝ ❢✉♥❝t✐♦♥s ❛♥❞ ❧♦❣❛r✐t❤♠✳ • ❲❡ ✉s❡❞ ❏✉❧✐❛ ❜❛s❡❞ ✐♠♣❧❡♠❡♥t❛t✐♦♥ ♦❢ t❤✐s ❢♦r♠❛❧ ♠❡t❤♦❞ t♦ ♦❜t❛✐♥ max T ( p, q ) ∈ [1 . 10751 , 1 . 10769] • ❚❤❡ ✷✲❧❡tt❡r ❚■◆ ❛❝❤✐❡✈❡s 2 R 1 + R 2 = 1 . 108141 ❛t t❤❡ ❞✐str✐❜✉t✐♦♥ P (( X 11 , X 12 ) = (0 , 0)) = p P (( X 11 , X 12 ) = (1 , 1)) = 1 − p P (( X 21 , X 22 ) = (0 , 0)) = 0 . 36 q P (( X 21 , X 22 ) = (1 , 1)) = 1 − 1 . 64 q P (( X 21 , X 22 ) = (0 , 1)) = 0 . 64 q P (( X 21 , X 22 ) = (1 , 0)) = 0 . 64 q ✇❤❡r❡ p = 0 . 507829413 ✱ q = 0 . 436538150 • ❘❡♣❡t✐t✐♦♥ ❝♦❞✐♥❣ ❛❝r♦ss t✐♠❡ s❡❡♠s t♦ ♦✉t♣❡r❢♦r♠ ♠❡♠♦r②❧❡ss ❝♦❞✐♥❣ ✸✹

  79. ■❢ s✉❜✲❛❞❞✐t✐✈❡✱ t❤❡♥ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♦♣t✐♠❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ ■❢ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡✱ t❤❡♥ ♦♥❡ s❤♦✉❧❞ ❜❡ ❛❜❧❡ t♦ ❞❡❞✉❝❡ ❛ ❝❤❛♥♥❡❧ ✇❤❡r❡ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♥♦t ♦♣t✐♠❛❧ ❘❡♠❛r❦s✿ ❈♦♥❥❡❝t✉r❡❞ t♦ ❜❡ s✉❜✲❛❞❞✐t✐✈❡ ✭❆♥❛♥t❤❛r❛♠✲●♦❤❛r✐✲◆❛✐r ✬✶✸✮ ❚♦ ❡✈❛❧✉❛t❡ t❤❡ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ❙✉✣❝❡s t♦ ❝♦♥s✐❞❡r ✿ ✳ ❲❡ ❞✐❞ ♥♦t ❣❡t ❛♥② ❝♦♥tr❛❞✐❝t✐♦♥ t♦ s✉❜✲❛❞❞✐✈✐t② ❢♦r ❜✐♥❛r② ✐♥♣✉t ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ❈❛♥ ♣r♦✈❡ s✉❜✲❛❞❞✐t✐✈✐t② ✇❤❡♥ ♦r ✳ ❲❤❛t ❛❜♦✉t ▼❛rt♦♥✬s r❡❣✐♦♥ ❢♦r t❤❡ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ■s t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡ ♦r ✐s t❤❡r❡ ❛♥ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡❄ ▲❡t W a ( y | x ) ❛♥❞ W b ( z | x ) ❜❡ ❣✐✈❡♥ ❝❤❛♥♥❡❧s✱ α ∈ [0 , 1] ✱ ❛♥❞ λ ≥ 1 ✳ � � C µ X ( λ − α ) H ( Y ) − αH ( Z ) + max p ( u,v | x ) { λI ( U ; Y ) + I ( V ; Z ) − I ( U ; V ) } ✸✺

  80. ❘❡♠❛r❦s✿ ❈♦♥❥❡❝t✉r❡❞ t♦ ❜❡ s✉❜✲❛❞❞✐t✐✈❡ ✭❆♥❛♥t❤❛r❛♠✲●♦❤❛r✐✲◆❛✐r ✬✶✸✮ ❚♦ ❡✈❛❧✉❛t❡ t❤❡ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ❙✉✣❝❡s t♦ ❝♦♥s✐❞❡r ✿ ✳ ❲❡ ❞✐❞ ♥♦t ❣❡t ❛♥② ❝♦♥tr❛❞✐❝t✐♦♥ t♦ s✉❜✲❛❞❞✐✈✐t② ❢♦r ❜✐♥❛r② ✐♥♣✉t ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s ❈❛♥ ♣r♦✈❡ s✉❜✲❛❞❞✐t✐✈✐t② ✇❤❡♥ ♦r ✳ ❲❤❛t ❛❜♦✉t ▼❛rt♦♥✬s r❡❣✐♦♥ ❢♦r t❤❡ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ■s t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡ ♦r ✐s t❤❡r❡ ❛♥ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡❄ ▲❡t W a ( y | x ) ❛♥❞ W b ( z | x ) ❜❡ ❣✐✈❡♥ ❝❤❛♥♥❡❧s✱ α ∈ [0 , 1] ✱ ❛♥❞ λ ≥ 1 ✳ � � C µ X ( λ − α ) H ( Y ) − αH ( Z ) + max p ( u,v | x ) { λI ( U ; Y ) + I ( V ; Z ) − I ( U ; V ) } • ■❢ s✉❜✲❛❞❞✐t✐✈❡✱ t❤❡♥ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♦♣t✐♠❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ • ■❢ ∃ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡✱ t❤❡♥ ♦♥❡ s❤♦✉❧❞ ❜❡ ❛❜❧❡ t♦ ❞❡❞✉❝❡ ❛ ❝❤❛♥♥❡❧ ✇❤❡r❡ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♥♦t ♦♣t✐♠❛❧ ✸✺

  81. ❲❤❛t ❛❜♦✉t ▼❛rt♦♥✬s r❡❣✐♦♥ ❢♦r t❤❡ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧❄ ■s t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥❛❧ s✉❜✲❛❞❞✐t✐✈❡ ♦r ✐s t❤❡r❡ ❛♥ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡❄ ▲❡t W a ( y | x ) ❛♥❞ W b ( z | x ) ❜❡ ❣✐✈❡♥ ❝❤❛♥♥❡❧s✱ α ∈ [0 , 1] ✱ ❛♥❞ λ ≥ 1 ✳ � � C µ X ( λ − α ) H ( Y ) − αH ( Z ) + max p ( u,v | x ) { λI ( U ; Y ) + I ( V ; Z ) − I ( U ; V ) } • ■❢ s✉❜✲❛❞❞✐t✐✈❡✱ t❤❡♥ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♦♣t✐♠❛❧ ❢♦r ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ • ■❢ ∃ ❡①❛♠♣❧❡ ✇❤❡r❡ ✐t ✐s s✉♣❡r✲❛❞❞✐t✐✈❡✱ t❤❡♥ ♦♥❡ s❤♦✉❧❞ ❜❡ ❛❜❧❡ t♦ ❞❡❞✉❝❡ ❛ ❝❤❛♥♥❡❧ ✇❤❡r❡ ▼❛rt♦♥✬s r❡❣✐♦♥ ✐s ♥♦t ♦♣t✐♠❛❧ ❘❡♠❛r❦s✿ • ❈♦♥❥❡❝t✉r❡❞ t♦ ❜❡ s✉❜✲❛❞❞✐t✐✈❡ ✭❆♥❛♥t❤❛r❛♠✲●♦❤❛r✐✲◆❛✐r ✬✶✸✮ • ❚♦ ❡✈❛❧✉❛t❡ t❤❡ ❝♦♥❝❛✈❡ ❡♥✈❡❧♦♣❡ ⋆ ❙✉✣❝❡s t♦ ❝♦♥s✐❞❡r ( U, V ) ✿ | U | + | V | ≤ | X | + 1 ✳ ⋆ ❲❡ ❞✐❞ ♥♦t ❣❡t ❛♥② ❝♦♥tr❛❞✐❝t✐♦♥ t♦ s✉❜✲❛❞❞✐✈✐t② ❢♦r ❜✐♥❛r② ✐♥♣✉t ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧s • ❈❛♥ ♣r♦✈❡ s✉❜✲❛❞❞✐t✐✈✐t② ✇❤❡♥ α = 0 ♦r α = 1 ✳ ✸✺

  82. ❚❤✐s ✐❞❡❛ ✇❛s ❛❧s♦ ✉s❡❞ t♦ r❡s♦❧✈❡ ✽✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r t❤❡ ❣❡♥❡r❛❧ ✸✲r❡❝❡✐✈❡r ❉▼✲❇❈ ✇✐t❤ ♦♥❡ ♠❡ss❛❣❡ t♦ ❛❧❧ t❤r❡❡ r❡❝❡✐✈❡rs ❛♥❞ ❛♥♦t❤❡r ♠❡ss❛❣❡ t♦ t✇♦ r❡❝❡✐✈❡rs❄ ◆❖ ✭◆❛✐r✱❨❛③❞❛♥♣❛♥❛❤ ✬✶✼✮ ❘❡♠❛r❦s • ■❞❡❛✿ ❚♦ ❞❡♠♦♥str❛t❡ s✉♣❡r✲❛❞❞✐t✐✈✐t② • ❉✐✣❝✉❧t② ✿ ■❞❡♥t✐❢② ❛ s✉✣❝✐❡♥t❧② s✐♠♣❧❡ ❝❧❛ss ✇❤❡r❡ ⋆ ❊✈❛❧✉❛t✐♦♥ ♦❢ t❤❡ r❡❣✐♦♥ ✐s ♣♦ss✐❜❧❡ ✿ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ⋆ ❙✉♣❡r✲❛❞❞✐t✐✈✐t② ❤♦❧❞s ✸✻

  83. ❘❡♠❛r❦s • ■❞❡❛✿ ❚♦ ❞❡♠♦♥str❛t❡ s✉♣❡r✲❛❞❞✐t✐✈✐t② • ❉✐✣❝✉❧t② ✿ ■❞❡♥t✐❢② ❛ s✉✣❝✐❡♥t❧② s✐♠♣❧❡ ❝❧❛ss ✇❤❡r❡ ⋆ ❊✈❛❧✉❛t✐♦♥ ♦❢ t❤❡ r❡❣✐♦♥ ✐s ♣♦ss✐❜❧❡ ✿ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ⋆ ❙✉♣❡r✲❛❞❞✐t✐✈✐t② ❤♦❧❞s ❚❤✐s ✐❞❡❛ ✇❛s ❛❧s♦ ✉s❡❞ t♦ r❡s♦❧✈❡ ✽✳✷ ■s s✉♣❡r♣♦s✐t✐♦♥ ❝♦❞✐♥❣ ♦♣t✐♠❛❧ ❢♦r t❤❡ ❣❡♥❡r❛❧ ✸✲r❡❝❡✐✈❡r ❉▼✲❇❈ ✇✐t❤ ♦♥❡ ♠❡ss❛❣❡ t♦ ❛❧❧ t❤r❡❡ r❡❝❡✐✈❡rs ❛♥❞ ❛♥♦t❤❡r ♠❡ss❛❣❡ t♦ t✇♦ r❡❝❡✐✈❡rs❄ ◆❖ ✭◆❛✐r✱❨❛③❞❛♥♣❛♥❛❤ ✬✶✼✮ ✸✻

  84. ❖✉t❧✐♥❡ • ❇r♦❛❞❝❛st ❝❤❛♥♥❡❧✿ ❊st❛❜❧✐s❤✐♥❣ ♦♣t✐♠❛❧✐t② ♦❢ ▼❛rt♦♥✬s ❢♦r ▼■▼❖ ❜r♦❛❞❝❛st ❝❤❛♥♥❡❧ • ■♥t❡r❢❡r❡♥❝❡ ❝❤❛♥♥❡❧✿ ❙✉❜✲♦♣t✐♠❛❧✐t② ♦❢ t❤❡ ❍❛♥✕❑♦❜❛②❛s❤✐ r❡❣✐♦♥ • ❋❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ⋆ ❘❡❧❛t✐♦♥ t♦ ♣r♦❜❧❡♠s ♦❢ ✐♥t❡r❡st ✐♥ ♦t❤❡r ✜❡❧❞s ⋆ ❯♥✐❢②✐♥❣ ♦❜s❡r✈❛t✐♦♥s ❛♥❞ s♦♠❡ ❝♦♥❥❡❝t✉r❡s ✸✼

  85. ❯s✐♥❣ ❋❡♥❝❤❡❧ ❞✉❛❧✐t② t❤✐s ✐s s❛♠❡ ❛s ❆ s♣❡❝✐✜❝ ❢❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ❙❤♦✇s ✉♣ ✿ ❚❡st✐♥❣ t❤❡ ♦♣t✐♠❛❧✐t② ♦❢ ❝♦❞✐♥❣ s❝❤❡♠❡s ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ✭✉s✉❛❧❧②✮ r❡❞✉❝❡s t♦ t❡st✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ � � � C ν X , α S ∈ R . α S H ( X S ) S ⊆ [ n ] ✸✽

  86. ❆ s♣❡❝✐✜❝ ❢❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ❙❤♦✇s ✉♣ ✿ ❚❡st✐♥❣ t❤❡ ♦♣t✐♠❛❧✐t② ♦❢ ❝♦❞✐♥❣ s❝❤❡♠❡s ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ✭✉s✉❛❧❧②✮ r❡❞✉❝❡s t♦ t❡st✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ � � � C ν X , α S ∈ R . α S H ( X S ) S ⊆ [ n ] ❯s✐♥❣ ❋❡♥❝❤❡❧ ❞✉❛❧✐t② t❤✐s ✐s s❛♠❡ ❛s � G 1 ( γ 1 ) := max α S H ( X S ) − E( γ 1 ( X )) µ X S ⊆ [ n ] � α S H ( X S ) − E( γ 2 ( X )) G 2 ( γ 2 ) := max µ X S ⊆ [ n ] � G 12 ( γ 1 , γ 2 ) := max α S H ( X 1 S , X 2 S ) − E( γ 1 ( X 1 )) − E( γ 2 ( X 2 )) µ X 1 , X 2 S ⊆ [ n ] ■s G 12 ( γ 1 , γ 2 ) = G 1 ( γ 1 ) + G 2 ( γ 2 ) ∀ γ 1 , γ 2 ❄ ✐✳❡✳ ■s t❤❡ ♠❛①✐♠✐③❡r ♦❢ G 12 ❛ ♣r♦❞✉❝t ❞✐str✐❜✉t✐♦♥❄ ✸✽

  87. ❆ s♣❡❝✐✜❝ ❢❛♠✐❧② ♦❢ ♥♦♥✲❝♦♥✈❡① ♦♣t✐♠✐③❛t✐♦♥ ♣r♦❜❧❡♠s ❙❤♦✇s ✉♣ ✿ ❚❡st✐♥❣ t❤❡ ♦♣t✐♠❛❧✐t② ♦❢ ❝♦❞✐♥❣ s❝❤❡♠❡s ❚❡st✐♥❣ ♦♣t✐♠❛❧✐t② ✭✉s✉❛❧❧②✮ r❡❞✉❝❡s t♦ t❡st✐♥❣ s✉❜✲❛❞❞✐t✐✈✐t② ♦❢ � � � C ν X , α S ∈ R . α S H ( X S ) S ⊆ [ n ] ❯s✐♥❣ ❋❡♥❝❤❡❧ ❞✉❛❧✐t② t❤✐s ✐s s❛♠❡ ❛s � G 1 ( γ 1 ) := max α S H ( X S ) − E( γ 1 ( X )) µ X S ⊆ [ n ] � α S H ( X S ) − E( γ 2 ( X )) G 2 ( γ 2 ) := max µ X S ⊆ [ n ] � G 12 ( γ 1 , γ 2 ) := max α S H ( X 1 S , X 2 S ) − E( γ 1 ( X 1 )) − E( γ 2 ( X 2 )) µ X 1 , X 2 S ⊆ [ n ] ❆r❡ t❤❡r❡ ♦t❤❡r ✜❡❧❞s ✇❤❡r❡ t❤❡ s❛♠❡ ❢❛♠✐❧② s❤♦✇s ✉♣❄ ✸✽

  88. ❚❤✐s ✭s❡r❡♥❞✐♣✐t♦✉s✮ r❡❞✐s❝♦✈❡r② ♦❢ t❤❡ ❧✐♥❦ ❜❡t✇❡❡♥ ❤②♣❡r❝♦♥tr❛❝t✐✈✐t② ❛♥❞ ✐♥❢♦r♠❛t✐♦♥ ♠❡❛s✉r❡s ❛♥❞ t❤❡s❡ ❡q✉✐✈❛❧❡♥t ❝❤❛r❛❝t❡r✐③❛t✐♦♥s ✐s s♣✉rr✐♥❣ ❛ ❧♦t ♦❢ ✇♦r❦ ❍②♣❡r❝♦♥tr❛❝t✐✈✐t② ❙t✉❞✐❡❞ ✐♥ ❢✉♥❝t✐♦♥❛❧ ❛♥❛❧②s✐s✱ ❝s t❤❡♦r②✱ ❡t❝✳ ❉❡✜♥✐t✐♦♥ ( X, Y ) ∼ µ XY ✐s ( p, q ) ✲❤②♣❡r❝♦♥tr❛❝t✐✈❡ ❢♦r 1 ≤ q ≤ p ✐❢ � Tg � p ≤ � g � q ∀ g ( Y ) ✇❤❡r❡ T ✐s t❤❡ ▼❛r❦♦✈ ♦♣❡r❛t♦r ❝❤❛r❛❝t❡r✐③❡❞ ❜② µ Y | X 1 p ✳ ❍❡r❡ � Z � p = E ( | Z | p ) ✸✾

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend


More recommend