English: This slide deck introduces amazing graphs which are drawn by listed Japanese companies in 2021.
Japanese: このスライドでは2021年に上場企業によって描かれたすごいグラフを紹介します。
English: This slide deck introduces amazing graphs which are drawn by listed Japanese companies in 2021.
Japanese: このスライドでは2021年に上場企業によって描かれたすごいグラフを紹介します。
Similar to 位置情報SNSのチェックインデータを用いたユーザの傾向の分析と位置予測 (20)
10. よくある手法
10
A B C D
E F G H
I J K L
M N O P
Q R S T
R -> N -> J -> I -> E -> A
L -> H -> C -> G -> J -> N -> R -> Q
M -> N -> K -> G -> D
メッシュ化して、どこに行ったかをシーケンスとして表した研究が多かった。
よく使われていた手法を2つほど紹介
• 頻出パターン: シーケンシャルパターンマイニング
• 軌跡類似度: シーケンスアラインメント
38. DPMU (Diffusion-type Periodic Model with similar Users)
• 同じ時間帯の分布を平均することで特定時刻にどこにいるか
を確率で表すモデルを構築
• 予測するにあたって予測対象ユーザと近いユーザの分布も利
用
38
time
・・
・
k+1(1day) k+2(1day)k(1day)
In the result, we changed checkin sequence to the probability distribution of user location.
This distribution is defined in continuous time.
I don’t have much time today, let me skip the detail of previous research.
Let me move on how to predict users’ location from the user distribution.
From now on, I’ll explain why our previous methods doesn’t suit to prediction and how to improve it.
As we defined, expansion of user distribution is limited between checkins.
But, after last checkin, the distribution is expanding as time advances because it moves like a free particle.
There is no constraint after last checkin.
In other word, the distribution becomes close to uniform eventually.
Prediction model predicts users’ future locations. We have to predict user’s location after last checkin.
So, the distribution is not adequate to predict user location.
We can’t use the model for prediction model as it is.
Some previous researches found that users’ check-ins appears regularly.
Especially, daily regularity is prominently observable.
So, we use daily regularity in our prediction model.
This is how to create the prediction model with users’ daily regularity.
We discretized the distribution into hours.
We grouped the distribution by days and average the probability distributions.
As the results, we have 24 spatial distributions for each user.