Is there a word for this?

There has to be, but I don't know what it is, and I wish to be informed. Especially you, science-y types. So, today apparently someone came out with a study which says that CEOs with big heads are great. No, really. Now, this sort of thing happens all the time. It's often reported as 'having a wide head makes you a great CEO!', and then boards of directors throw out all their selection criteria and just hire the applicant with the biggest head, and then they wonder why it doesn't turn out terribly well. What's really happening in this kind of case, of course, is that the science of choosing a good CEO (or whatever the context happens to be) has become so well-developed, and so shared by everyone actually involved in choosing CEOs, that either: a) factors which are very unimportant compared to other factors, but have a genuine effect, have their apparent effect magnified because the selection processes in use filter out all the more significant factors so, imagine intelligence accounts for 80% of good-CEO-ness, social skills 15%, business experience 4%, and miscellaneous 1%, of which 'having a big head' is probably 0.5%. But boards all know about intelligence, social skills, and business experience, so they pick intelligent, socially-skilled and experienced people to be CEOs; the factors that account for 1% of good-CEO-ness are the only ones that now *vary* in the sample set, so their apparent influence becomes greatly magnified, and shallow thinkers believe that having a big head makes you a great CEO. or, b) all of the above except that having a big head is not a determining factor in being a good CEO *at all* and it's sheer randomness at work: out of all the completely unimportant attributes of CEOs that vary, one which happened by complete chance to coincide with 'good-CEO-ness' in the sample set is 'having a big head'. I'm sure this happens all the time, and I'm sure statisticians are aware of it and try to account for it and it's completely muffed by the general press, as is usually the case with Hard Science Stuff: but I don't know if there's a general term for the effect. Anyone?