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Anonymous
Anonymous
14 years ago

We most often watch for
We most often watch for f'(x)=0 in anticipation of an inflection point, with the hope that this signals a local extremum. I don’t believe that there is any fundamental reason that we could not see f'(x)->0 as a signal that we are going asymptotic.

EJ
EJ
14 years ago
Reply to  Anonymous

SDnonSerfer wrote:We most
[quote=SDnonSerfer]We most often watch for f'(x)=0 in anticipation of an inflection point, with the hope that this signals a local extremum. I don’t believe that there is any fundamental reason that we could not see f'(x)->0 as a signal that we are going asymptotic.[/quote]

f'(x) = 0 is a local minimum or maximum
f”(x) = 0 are inflection points

From the graph, f'(x) is definitely positive, however it does appear that f”(x) may be 0. Doubt this means an immediate change in trend, based on previous data scatter.

sdduuuude
14 years ago
Reply to  EJ

EJ, I almost posted the exact
EJ, I almost posted the exact same comment.
Assuming x = # of jobs, yes f”(x) = 0 is an inflection point in the jobs vs. time graph.

But, I think he was trying to say we are at an inflection point of the growth rate, which is f”'(jobs) = f”(growth) = 0. I think.

creative_cpa
14 years ago

Non-seasonally adjusted
Non-seasonally adjusted numbers show that the civilian labor force in all of California dropped 48,000 more between October 2009 and November 2009. The ranks of the employed dropped another 21,000 and the ranks of the unemployed dropped 28,000. So, it seems the entire drop in the California unemployment rate between October and November can be explained by unemployed people leaving the state. More importantly, every month there are fewer people employed in California. If the last employed person in California lost his job, would you opine that things are looking up because the job losses are over? When looking at year-over-year trends, it is also important to look at the aggregate numbers.

(former)FormerSanDiegan
Reply to  creative_cpa

creative_cpa
[quote=creative_cpa]Non-seasonally adjusted numbers show that the civilian labor force in all of California dropped 48,000 more between October 2009 and November 2009. The ranks of the employed dropped another 21,000 and the ranks of the unemployed dropped 28,000. So, it seems the entire drop in the California unemployment rate between October and November can be explained by unemployed people leaving the state. More importantly, every month there are fewer people employed in California. If the last employed person in California lost his job, would you opine that things are looking up because the job losses are over? When looking at year-over-year trends, it is also important to look at the aggregate numbers.[/quote]

When rebuffing an article, it is also important to address the appropriate geographical area. The article addressed San Diego.

Edit : I see Rich beat me to the punch.

creative_cpa
14 years ago

Yes, I am aware that I used
Yes, I am aware that I used the broader geographic area as an example. But my statements are still relevant if you only look at the San Diego numbers. In November, San Diego lost 2,700 people from its workforce. This was comprised of 3,000 more employed (which is mostly seasonal retail if you look at the details), offset by 5,600 fewer unemployed. So most of the drop in the unemployment rate comes from unemployed people leaving the County, not job growth.

But why focus so narrowly on only San Diego County? The numbers developed by California are based upon the political boundaries of San Diego County, not economic spheres of influence. If economic influence were considered, Temecula and parts of Southern Orange County should be included.

My point remains. It is interesting to look at your first derivative computations to find inflection points, but do not exclude the big picture. Imagine you are on a roller coaster ride and you have reached the bottom of a dip and the car starts to climb to the top of the next peak. Suddenly the earth opens up and the entire roller coaster, cars and all, starts dropping into the bowels of the earth. Would you just look at the track ahead of you and smile smugly because you are going up to the next peak?

EconProf
14 years ago

Those are fair criticisms of
Those are fair criticisms of CPA. But the
broader point remains…CA’s future looks bleak if it is in the throes of an outmigration. Why buy RE in a state that drives out its middle class to states with more hospitable business and tax climates.

EconProf
14 years ago

Those are fair criticisms of
Those are fair criticisms of CPA. But the
broader point remains…CA’s future looks bleak if it is in the throes of an outmigration. Why buy RE in a state that drives out its middle class to states with more hospitable business and tax climates.

outtamojo
14 years ago
Reply to  EconProf

“Why buy RE in a state that
“Why buy RE in a state that drives out its middle class to states with more hospitable business and tax climates.”

‘Cause we like it here?