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Luminosity Functions

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Old August 17th 07, 10:53 PM posted to sci.astro.research
Steve Willner
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Default Luminosity Functions

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In article ,
"PoorRichard" writes:
My question is, what approach for computing a (meaningful) LF is

As it happens, I recently had to study LF calculations. The best
single source I found was the paper by Willmer (1997, AJ, 114, 898).

The bottom line is that there is no single "best" method. Questions
to ask: how many objects in your sample? Are they clustered? Do you
want to avoid binning the data? Are you willing to assume a
Schechter function or other functional form?

Among non-parametric methods, good old 1/V_max may be your only
choice if you have fewer than a thousand objects, but it requires
binning the data and is biased by clustering. If you have enough
objects, the Lynden-Bell C- method avoids these problems. If you are
willing to adopt a functional form in advance, maximum likelihood
(such as the STY method) is the way to go. Ideally you would try
more than one method and make sure they agree or at least that you
understand why not if they don't.

Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
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Old August 24th 07, 09:07 AM posted to sci.astro.research
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Posts: 6
Default Luminosity Functions

"Steve Willner" wrote in message
As it happens, I recently had to study LF calculations. The best
single source I found was the paper by Willmer (1997, AJ, 114, 898).

Hello. I read that paper by Willmer yesterday. An awesome resource, thank

[Mod. note: quoted text trimmed -- mjh]

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