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Preselection and processing of attributes
We should also only keep those attributes that we think could help the classifier
in determining the good from the not-so-good answers. Certainly, we need the
identification-related attributes to assign the correct answers to the questions.
Read the following attributes:
Chapter 5
• The PostType attribute, for example, is only necessary to distinguish
between questions and answers. Furthermore, we can distinguish between
them later by checking for the ParentId attribute. So, we keep it for
questions too, and set it to 1.
• The CreationDate attribute could be interesting to determine the time span
between posting the question and posting the individual answers, so we
keep it.
• The Score attribute is, of course, important as an indicator of the
community's evaluation.
• The ViewCount attribute, in contrast, is most likely of no use for our task.
Even if it is able to help the classifier distinguish between good and bad, we
will not have this information at the time when an answer is being submitted.
We will ignore it.
• The Body attribute obviously contains the most important information. As it
is encoded in HTML, we will have to decode it to plain text.
• The OwnerUserId attribute is useful only if we will take the user-dependent
features into account, which we won't. Although we drop it here, we
encourage you to use it (maybe in connection with users.xml) to build a
better classifier.
• The Title attribute is also ignored here, although it could add some more
information about the question.
• The CommentCount attribute is also ignored. Similar to ViewCount, it could
help the classifier with posts that were posted a while ago (more comments
are equal to more ambiguous posts). It will, however, not help the classifier
at the time that an answer is posted.
• The AcceptedAnswerId attribute is similar to the Score attribute, that is, it is
an indicator of a post's quality. As we will access this per answer, instead of
keeping this attribute, we will create a new attribute, IsAccepted, which will
be 0 or 1 for answers and ignored for questions (ParentId = 1).
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