How can a person be "half jewish". Its like saying a person is "half-Christian" or "half-Muslim". Either you are, or you aren't...
If only your father is Jewish are you Jewish? If your mother is Jewish you are Jewish but are you as Jewish as when both your parents are Jewish?
But "Jewish" is a religion they say, nothing to do with genes.

Most Jews in Israel are atheist, so they say, so wtf...