I just concluded a long, and understandably fairly contentious phone conversation with John McIntyre of Real Clear Politics.
John strongly disputes the notion that he is cherry-picking polls to achieve a particular partisan result (pro-GOP or otherwise).
It is clear to me that there is substantial subjectivity in how RCP selects the polls to include in its averages. RCP does not publish an FAQ, or any other set of standards. Nor, in my conversation with John, was he willing to articulate one. In my view, the fact that RCP does not disclose a set of standards means ipso facto that they are making judgment calls -- that there is some subjectivity involved -- in how their polls are selected.
However, it does not necessarily follow that these judgment calls reflect any deliberate partisan leaning, i.e. any "bias". That is a much stronger accusation, and it is the one that John objects to. I take John at his word that this is not the case. I hope to have a spirited rivalry with RCP, but my post this morning may have made things too personal.
At the same time, I believe that RCP leaves themselves open to this type of accusation until and unless they improve their level of disclosure. I have strongly encouraged John to publish an FAQ or other set of standards on his website.