TDEE for Swimming and Running

I find TDEE for running to be higher
when compared with a comparable swim.

Therefore, I am puzzled how people can
say: 1 Mile Swim = 4 Mile Run

The only thing I could find on where
this statement might come from
was a reference to Dr. Cooper
and an aerobic chart.

Anyhow, this just seems to go against
my own personal experience.

Does anyone have any valid scientific
research backing up such a claim?
What information I do have contradicts
such a claim(that is, from TDEE data).

--
conrad