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Comment other options ... (Score 1) 1067

I've often used "1" as a drop in when dividing by zero. also the logarithm of zero, i usually am working with information units, so it's plnp, and if p = 0, i just say that plnp = 0, and that's kind of like saying ln0 = 1.

i think mathematically infinity or negative infinity would make the most sense, unless its 0/0, in which case you'd apply l'hopital's rule. but i don't think the computers going to do that. another way is you could create another number system, that would run a tally of divides by zeros or multiplies by infinities, minus multiplies by zeros or divides by infinity. (and flipping the sign on negative infinity.)

Comment definitely c ironically the most object-orientatd (Score 1) 211

definitely c ironically the most modern programming language of the bunch.

maybe some day apple will finally get with the times and use an existing popular modern object orientated programming language like c++ or java.

you know, shortcut the whole process f making a feature-incomplete idiosyncratic and verbose programming programing language with inconsistent syntax and skip ahead to what everyone else had half a century ago.

why oh why don't they just use c++ or java?


Comment author evidences how bad U.S. science literacy is (Score 1) 795

the author shows by his very writing of the article just how bad science education is in the u.s. that is, he himself is a victim of the very low standards and the lack of teaching and emphasis on philosophy of science. the author should be ashamed and embarassed for being a shining example of everything that is wrong and antiquated with science education in america. his philosophy belongs to the pre-socratics; the sophists. there is nothing new in what he is saying, it is embarrassingly old. and embarrasingly banal.

if the article proves anything it's by way of example: the author is an excellent example of the people that our education system has left behind.

Comment planing to fail? (Score 1) 269

so what i get from the article.

1) they start by using a measure that's not at all even correlated with what they're interested in.
2) they then completely switch the measure, so then you have two completely unrelated filters on the data - and the data (dna) is very high dimensional, so your final result set is of course going to be miniscule and effectively random. and woe and behold, that's what they got.
3) on top of that they looked at the correlation between the first filter and the second and found woe and behold their method has no chance at all of telling them what they want to know - which we already knew in step 1.

so... uh... do they see what's wrong with their methodology? could it be more obvious? this was botched really badly.

Comment it varies wildly (Score 1) 2

it will vary widely depending on a number of things, including database indexes, system tables, machine specs, operating system, machine specs, recent table usage, table size, whether an execution plan is cached etc.

* machine specs - obviously, memory, cpu, hard drive bandwidth and seek time, etc.
* operating system - this will determine the memory paging, process threading, disk caching, etc.
* indexes - an execute statement on indexes vs not an indexes will make orders of magnitude difference, especially for larger tables
* recent table usage - determines whether the database is paged into memory.
* table size - determines how much of the tabe is paged into memory, and how many comparisions it will need to do to get a resultset, etc.
* system tables - contains optimization parameters that will effect performance and execution plan creation, such as how many rows are expected in the table. if these are off from reality, the database could use a poorly performing execution plan. system tables can also effect paging and other global parameters that effect performance.
* whether an execution plan is cached - determines whether the database will have to re-design an execution plan

all these things are going to add so much variance that it's gong to totally swamp any chance of apples-to-apples comparision.

to do a real comparision you really have to look at it on the logical level rather than the empirical level. what database algorithms will optimize better? etc.

all in all, you're probably just not doing it right. they should be about the same, except in exceptional cases.

Submission + - When Beliefs and Facts Collide

schnell writes: A New York Times article discusses a recent Yale study that shows that contrary to popular belief, increased scientific literacy does not correspond to increased belief in accepted scientific findings when it contradicts their religious or political views. The article notes that this is true across the political/religious spectrum and "factual and scientific evidence is often ineffective at reducing misperceptions and can even backfire on issues like weapons of mass destruction, health care reform and vaccines." So what is to be done? The article suggests that "we need to try to break the association between identity and factual beliefs on high-profile issues – for instance, by making clear that you can believe in human-induced climate change and still be a conservative Republican." But given the propensity of all humans towards cognitive bias and even magical thinking, should we just resign ourselves to the idea that democracies will never make their decisions based purely on science?

Submission + - Democracy crusaders scrambling to cross crowd funding finish line 1

SingleEntendre writes: Time is running out for the Mayday PAC to reach its latest crowd funding goal of $5M. The total currently stands at $4.5M. Led by Harvard Law Professor Lawrence Lessig, the Mayday PAC seeks to reduce the influence of money in US politics by 2016, primarily by identifying and supporting congressional candidates who share this vision. If phase 2 is successful, with matching funds the total raised will be $12M. A self-imposed deadline arrives at of midnight tonight, July 4th, Hawaii-Aleutian Standard Time (HAST).

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