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܈ऺ͔Βͷֶश
ճϞσϧ͔Βਪఆͨ͠ਖ਼ղΛར༻ͯ͠ྨϞσϧΛֶश
20
V. C. Raykar, S. Yu, L. H. Zhao, G. H. Valadez, C. Florin, L. Bogoni, and L. Moy: Learning from crowds. Journal of Machine Learning Research, 2010.
ྨϞσϧ
fw
(xi
) = Pr [yi
= 1 ∣ xi] =
1
1 + exp(−w⊤xi
)
ྨϞσϧͷֶशखॱʢऩଋ͢Δ·Ͱ܁Γฦ͢ʣ
&TUFQ
ճऀࠞಉߦྻΛݻఆͯ͠ਖ਼ղΛਪఆʢ%BXJE4LFOFͱಉ༷ʣ
.TUFQ
ਪఆͨ͠ਖ਼ղΛ༻͍ͯճऀࠞಉߦྻͱྨϞσϧΛߋ৽
௨ৗͷ܇࿅σʔλ {(xi
, yi
)} {(xi
, yi1
, yi2
, …)}
܈ऺ͔Βͷֶशͷ܇࿅σʔλ
ճϞσϧ
Pr[yij
∣ yi
= 1] = αyij
j
(1 − αj
)(1−yij
)
Pr[yij
∣ yi
= 0] = β(1−yij
)
j
(1 − βj
)yij