Rick, the reason that he presents is so obvious that it almost
hurts! The middle child or children have to share time with either
the first or last (or both if just 3). So what he is saying is that
the first child most assuredly has 1 or 2 yrs (typically I think) of
exclusive time. The middle child has no exclusive time and the last
child has some exclusive time when the 2nd child leaves.
···
On 05/30/2016 08:03 PM, Richard Marken
wrote:
[From Rick Marken (2016.05.30.1900)]
On Mon, May 30, 2016 at 3:35 AM, Alex
Gomez-Marin agomezmarin@gmail.com
wrote:
RM: Thanks for this Alex. I got my PhD at UCSB and it looks
like Gerd is making his presentation in the same room where I
gave my PhD talk.
Anyway, I see why you wanted us to take
a look at this. I didn;t watch the whole thing but Gerd’s 1/N
“Heuristic” looks a lot like a reference specification – in
the first example, a reference for the amount of time parents
spend with each child. I like the idea but I didn’t follow his
explanation of how the “heuristic” explains the shape of the
data for families with different numbers of kids with
different spacing between the kids.
RM: I like the idea a lot -- we would
say that he is modeling the parents as controlling for
allocating an equal time to the kids. But I don’t understand
why this doesn’t predict equal but overall less time for all
kids when there are different numbers of kids. I think I’m
missing what his assumption is about what the parents are
actually controlling for – that is, what is the controlled
variable? What is being made to match the heuristic?
Best
Rick
–
Richard S. Marken
Author, with Timothy A. Carey,
of Controlling
People: The Paradoxical Nature of Being
Human.
https://www.youtube.com/watch?v=Oo7sWUtApr4
Hey Rick, thanks.
BTW, noting what I actually wrote rather shocked me... or at least
the comment that I made. I had already noted that you stated that
you had not read the whole thing so my ‘…is so obvious…’ remark
must be understood as not having any reference to an opinion of your
comprehension!
Great point on the gaze heuristic. I did sort of ponder that for a
moment. I noted that I had not seen anything (even yet) on just
what that heuristic actually is beyond the loose reference to
‘maintaining a constant angle.’ Like yourself, is seriously doubt
that the fielder example is such a case or at least would typically
be such a case.
I don't know if this is 'way out on a limb' but I suspect that a
fielder probably controls head position and eye rotation in the
socket to do something like maintain the image of the ball centered
in the visual image. I think that it could well be more complex
than that where there might yet another object in the visual plane
that also must be tracked (where neither would be centered) but
essentially the changes in eye position and head position required
to maintain the ball at some referenced point in the full perceived
image would then be the input to yet another control system that
would, presumably through another heuristic, correct running
velocity to keep the ball’s visual position at the reference point
without the head or eye position sensors having to make changes.
I fully realize that even if what I just said about that is close to
what is true that it is still a gross oversimplification. Since
anyone that has successfully caught as opposed to falling down or
being hit by the ball realizes that in most cases the head has to
tilt back when the ball gets close to overhead just to see it.
···
On 05/31/2016 03:59 PM, Richard Marken
wrote:
[From
Rick Marken (2016.05.31.1500)]
RM: Thanks to Bill Leach and Vyv Huddy for explaining the
1/N “investment in child” heuristic.
On Mon, May 30,
2016 at 10:05 PM, Bill Leach <> wrote:
BL: Rick, the reason that he
presents is so obvious that it almost hurts!
Vyv
(31.05.2016 935 BST)]
VH:
He says that the first born and last
born are alone with the parents for a
certain amount of time (41.30). So there
is an assumption the children are born
in sequence and then fly the nest in
sequence. This means N increases for
each born and then decreases as
children leave. For families with more
than two children the middle born are
never alone so the average N is always
higher for them than for the first or
last born.
RM: Yes, it is quite simple. I guess my problem was
not carefully reading the y-axis label: “Child care
received over 18 years (hours)”. I thought they were
just measuring “investment” using hours during
childhood, which I think lasts until 12 at most, so
that all kids are in the house at the same time. The
fact that they managed to measure hours over 18 years
for each kid is amazing. The study must have started
quite some time ago.
RM: So their hypothesis is simply that parents try
to control for spending an equal amount of time with
each kid. A side effect of this is that the first and
last kid get more time spent with them from birth to
18 years assuming that all kids move out at 18. So the
dependent variable in this study – child care
received over 18 years (hours) – is assumed to be a
side effect of controlling for equal time with each
kid.
RM: It seems that a far easier way to test this
“equal time with each kid” (1/N) hypothesis would be
to monitor the amount of time parents of 2, 3 or 4
kids spend with each kid, perhaps measured over a
month.
VH:
Rick - what did you think of the “gaze
heuristic”?
RM: I've seen this hypothesis about the controlled
variable before. It’s on the right track, but it
obviously can’t be gaze (angle of the eyes/head) that
is controlled; it’s got to be a consequence of the
direction of gaze – visual angle – that is actually
controlled. I think they choose gaze as the variable
that is controlled because they just can’t get their
heads around the fact that organisms control input,
not output.
RM: By the way, can you think of a way to show that
gaze is not the variable that is controlled when
moving to intercept a ball (or avoid a boat coming at
you)? Hint: it would involve doing the Test for the
Controlled Variable.
Best
Rick
–
Richard S. Marken
Author, with Timothy A.
Carey, of Controlling
People: The Paradoxical Nature of
Being Human.
wrleach@cableone.net