Related to the posts of the last couple of days on “modeling” to “simplify complex situations…
“If you ask a physicist how long it would take for a marble to fall from the top of a ten-storey building, she will answer the question by assuming that the marble falls in a vacuum. Of course, this assumption is false. In fact, the building is surrounded by air, which exerts friction on the falling marble and slows it down. Yet the physicist will correctly point out that friction on the marble is so small that its effect is negligible. Assuming that the marble falls in a vacuum greatly simplifies the problem without substantially affecting the answer.”
Department of Fisheries and Oceans has developed a range of different computer models for modeling salmon run sizes (e.g. “simplifying complex situations): I think they’re working towards one per species… (see previous posts on to see some of these brilliant tools in action…)
Justice Cohen: ummm... I think it's supposed to be "in a vacuum"
–click the image to see it a bit bigger–