text: Title: probabilities_ outcome not consistent with get_document_info output
  Body: Hi Maarten,
  
  I found that `probabilities_` outcome is not always the same with the outcome of `get_document_info`.
  
  `topic_model.probabilities_[0]` gave me the following:
  
  `array([0.31045925, 0.0031012 , 0.00162018, 0.00349846, 0.0039572 ,
         0.01974048, 0.00788453, 0.00418387, 0.00252376, 0.00240863,
         0.00308729, 0.00263459, 0.00250224, 0.00254411, 0.00254329,
         0.00283324, 0.00229805, 0.00638228, 0.00281222, 0.0028788 ,
         0.00298958, 0.0030663 , 0.00246619, 0.00387198, 0.00227671,
         0.00254577, 0.00245718, 0.0026639 , 0.00243602, 0.00419228,
         0.00243791, 0.00244527, 0.00384736, 0.00285853, 0.00214743,
         0.00218918, 0.0029944 ])`
  
  From this output it seems that the dominant topic would be Topic 0.
  
  However, `get_document_info` gave me this:
  
  Document                   在中国 嫦娥五号 探月工程 顺利实施 之际 美国 在航天 领域 频频 动作 退出_开放天空条...  
  Topic                                                                      5
  Name                                                      5_太空_卫星_外空_外空_攻防对抗
  Representation             [太空, 卫星, 外空, 外空_攻防对抗, 外空_攻防对抗 准备, 外空安全, 发射, 航天...
  Representative_Docs        [进入 世纪 以来 国际社会 围绕 外层空间 争夺 日益 激烈 外空安全 形势 日趋_紧张 ...
  Top_n_words                太空 - 卫星 - 外空 - 外空_攻防对抗 - 外空_攻防对抗 准备 - 外空安全 - 发...
  Probability                                                         0.310459
  Representative_document                                                False
  Name: 0, dtype: object
  
  This output shows the same highest `Probability` (which is 0.310459) but assigns the document to Topic 5 instead of Topic 0.
  
  Any solutions to this issue? Thanks much for the help!
  
  
  
  
  
  