Wayne Grudem's survey of 2,336+ uses of kephale — Cohick's misleading summary of his work

Wayne Grudem surveyed over 2,000 examples of kephale in the ancient world. Cohick summarizes this as finding that only 2.1% of the time kephale should be translated as 'leader or authority over.' But this statistic includes literal uses of 'head' (physical head), which are obviously not what Paul means. When you exclude literal uses, Grudem found that 16.2% of metaphorical uses mean 'person of superior rank, ruler, or ruling part.' Cohick's summary involves 'statistical trickery.'