DEIM Forum 15 A5-1 35 855 1- E-mail: {yamahei,satoh}@ce.slis.tsukuba.ac.jp Twitter Twitter 1. Twitter 1 Twitter Twitter Twitter [15] 1 1 5 1 3 7 3 1https://twitter.com/ https://twitter.com/who to follow/interests 3http://naojcamp.mtk.nao.ac.jp/phenomena/151/ Number of tweets May 1, 1 weekday Annular Solar Eclipse : 3: 6: 9: 1: 15: 18: 1: : time 1 1 5 1 [1]

Twitter 3 5 6. Twitter. 1 Twitter Weng [1] Twitter PageRank TwitterRank Cha [] Twitter 1 Pal [7] authority non-authority authority Sae-Trumper [8]. Twitter [1] [13] Yamaguchi [11] Twitter 3. 3. 1 i s n i,s S N i = {n i,1, n i,,, n i,s} n i,s µ i σ i N i µ i σ i µ i = 1 S n i,s, σ i = 1 S (n i,s µ i ). (1) 1 i,s i,s = n i,s µ i σ i. () i,s s i s b i,s 1 if i,s > 3σ i, b i,s = otherwise, i B i = {b i,1, b i,,, b i,s} 3. (3) 1 [1] 3.. 1 [1]

3.. [3] 1 i,s i,s 3. 3 3. i s b i,s s k p s,k i k S b (i, k) S b (i, k) = b i,s p s,k. () i k s S b (i, k) 1 i s i,s S (i, k) = i,s p s,k. (5) i s i,s k s k Mean 15 1 5 5 1 15 Standard deviation µ i σ i.. 1 1 5 1 13 3 1 Twitter Search API s 1 µ i σ i 1 1. 51,889 1 µ i σ i 1 9 61,6 1 51,89. 3 1 5 1 1 6 6 AKB8 1 1 31 13 1 1 13 3 8 http://search.twitter.com/search.json

Number of bursts 5 5 35 3 5 15 1 5 1-5 Annular solar eclipse 3 AKB8 general election New year WBC 1-6 1-7 1-8 1-9 1-1 1-11 1-1 13-1 13-13-3 13-13-5 WBC. 3 i,s α β [] α = 5 β =.1 K 1 [9] 1%.58 6 s p s,k 1 5 1 (a)(b)(e)(f) (c)(d) (f) 1 9 5 (a)(b)(e)(f) (c)(d) 1 3.. 3 6 S b S i m(i) m(i) = S b i,s rel(s, i) S bi,s (6) rel(s, i) i s 1 1 6 i m(i) = 1 m(i) = ndcg [5] ndcg ndcg l = DCG l (7) IDCG l l m(ir) 1 DCG l = log (1 + r) r=1 i r r IDCG l l DCG l l 1 < = l < =. 5 ndcg ndcg.71 (a) ndcg.9 (d) (b)(c)(d)(e)(f) S b (b)(c)(f) (a)(d)(e) 1 Twitter (a) @eva information (d) @Nintendo i,s 5 6 i,s i,s i,s (a) i,s 1 5 1 11 1 1 11

.9.8.7.6.5..3..1 1-5.9.8.7.6.5..3..1 1-5.9.8.7.6.5..3..1 1-5 1-6 1-7 1-8 1-9 1-1 1-6 1-7 1-8 1-9 1-1 1-6 1-7 1-8 1-9 1-1 1-11 (a) 1-11 (c) 1-11 (e) Spearman s ρ =.667 1-1 13-1 13-13-3 13-13-5 Spearman s ρ =.68 1-1 13-1 13-13-3 13-13-5 Spearman s ρ =.81 1-1 13-1 13-13-3 13-13-5.8.7.6.5..3..1 1-5.9.8.7.6.5..3..1 1-5.7.6.5..3..1 1-6 1-7 1-8 1-9 1-1 1-6 1-7 1-8 1-9 1-1 1-5 1-6 1-7 1-8 1-9 1-1 1-11 (b) 1-11 (d) 1-11 (f) Spearman s ρ =.685 1-1 13-1 13-13-3 13-13-5 Spearman s ρ =.885 1-1 13-1 13-13-3 13-13-5 Spearman s ρ =.99 1-1 13-1 13-13-3 13-13-5 1 (a) (b) (c) (d) (e) (f) 1 #eva #FNS #chukoi #NintendoDirectJP # #AKB8 #ntv #fujitv # #nyaruko # #AKB 3 #join eva #agqr #tx kodokugurume #agqr #ntv #AKBvote1 # #TFBJP #tokyomx #followback # #akbsenkyo 5 #evangellion # #tvtokyo #E3 # #akb8 ndcg@ (a) (b) (c) (d) (e) (f) S b.731.99.91.938.799.958.69.913.919.95.86.87 S.71.87.813.939.789.958.738.87.86.97.88.951.71.89.865.9.86.98 (d) i,s i,s 5. 5. 1 (a) ndcg@.8 6 5 S b i,s S ndcg (c) S b S.1 ndcg (c) S (c) 1 9 13 1 [11] i,s i,s

Cosine similarity.9.8.7.6.5..3..1 1-5.9.8.7.6.5..3..1 1-5.9.8.7.6.5..3..1 1-6 1-7 1-8 1-9 1-1 1-11 1-1 13-1 13-13-3 13-13-5 (a) @eva information i,s 1-6 1-7 1-8 5 1-9 1-1 1-11 1-1 5.5 3.5 3.5 1.5 1.5 -.5 value.9.8.7.6.5..3..1 1-5 1-6 1-7 1-8 1-9 1-1 1-11 1-1 13-1 13-13-3 13-13-5 (a) i,s (a) S () (d) @Nintendo i,s 6 13-1 13-13-3 13-13-5 7 6 5 3 1-1 value.9.8.7.6.5..3..1 1-5 1-6 1-7 1-8 1-9 1-1 1-11 1-1 13-1 13-13-3 13-13-5 (d) i,s (d) S b () Pearson s r =.8 Cosine similarity.7.6.5..3. 18 16 1 1 1 8 6-1 1 8 6 - Pearson s r =.3 value value.5 1 1.5.5 3 3.5 Proposal score (S :).1..3..5.6.7.8.9 Proposal score (S b :) (a) 7 (d) (f) ndcg (f) 1 9 (f) 1 AKB8 1 9 18 AKB8 9th 5 AKB8 (f) ndcg (d) 13 6 @Nintendo 13 17 3 Nintendo Direct Luigi special 6 5. 56 5http://ja.wikipedia.org/wiki/AKB8 9th 6http://ja.wikipedia.org/wiki/Nintendo Direct

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