M.I.5¾ wrote:
> "Mentalguy2k8" wrote in message
> news:mN74l.32197$er1.30363@newsfe18.ams2...
>>
>> "Norman Wells" wrote in message
>> news:gG74l.54521$Ci.8166@newsfe10.ams2...
>>> judith wrote:
>>>> I frequent that rather odd place uk.rec.cycling - one of the
>>>> phrases which is used time and time again is above - as in:
>>>>
>>>> "No-one has ever proved that cycle helmets make cycling any safer
>>>> at the population level"
>>>>
>>>> "population-level studies that show little or no positive
>>>> effects of large secular changes in helmet wearing.
>>>>
>>>> despite asking what people think the phrase means no one has said.
>>>>
>>>> Guesses - suggestions?
>>>>
>>>> Can the "population" be any size you choose?
>>>
>>> In statistics, the term 'population' means the entire aggregation of
>>> items from which samples can be drawn. So, for example, if all of
>>> the 60 million people living in the UK are possible cyclists then
>>> the relevant 'population' for any statistical survey is 60 million.
> And the person doing the talking (Norman) doesn't know anything about
> anything at all as he frequently demonstrates to this group (though
> rather less so of late).
How would you know? You keep saying you've killfiled me!
I think I've actually got a secret shadow who can't keep the cat in the bag.
> He clearly knows nothing of statistics
> because the whole point of using a sample to predict something about
> the population as a whole is that the sample can be deliberately
> biased in a number of ways so that the prediction is in fact what you
> want to prove rather than any meaningful analysis.
Well, that's statistics put away for good then. Can't play with them any
more.
> The confidence
> level is thus nearer zero than anything in the 90 percent range.
Such a pity that mathematical concepts are a foreign land to the uneducated.
> But of course the OP didn't ask what 'population' meant but what
> 'population level' meant.
Well, actually, the question was 'Can the "population" be any size you
choose?'.
At least I attempted to answer it.
Which is rather more than you, whatever you thought the question was.
> Now watch Norman demonstrate that he doesn't understand the concept
> of a killfile either as he directs a probably wrong answer at me in
> spite of the fact that I won't see it (unless someone who hasn't
> killfiled him is stupid enough to respond).
Oh gosh, I clearly don't understand! I thought a killfile meant the person
using it was deaf to those in it. I didn't think it meant those in it
weren't allowed to speak.
Sorry, my mistake obviously.
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