# statistically significant from 0



## Sac

Hola,

La frase completa es ésta: 

The average slope between 3 and 12 months is not statistically significant from 0 (p=0.45).

Éste es mi intento: 

El promedio de la pendiente entre los meses 3 y 12 no es significativo estadísticamente de 0 (p = 0,45).

Pero me suena muy raro, no recuerdo mucho de estadística, qué opinan uds? 

Saludos.


----------



## greenheyes

Creo que quiere decir " estadísticamente, no se diferencia significativamente de 0"


----------



## Outsider

Sac said:


> La frase completa es ésta:
> 
> The average slope between 3 and 12 months is not statistically significant from 0 (p=0.45).


Seguramente, la frase tiene un error, y debería ser "The average slope between 3 and 12 months is not statistically *different* from 0 (p=0.45)".


----------



## mhp

Outsider said:


> Seguramente, la frase tiene un error, y debería ser "The average slope between 3 and 12 months is not statistically *different* from 0 (p=0.45)".


    That replacement would change the meaning of the sentence. If you say “it is not (statistically or otherwise) different from zero” that suggests that (statistically or otherwise) it is zero. Here, ‘significant’ refers to rounding error when a certain number of significant figures are considered in a measurement. Also see Google Scholar: significant from zero.


----------



## triumphraptor

I have to disagree with mhp politely, and agree with Outsider. This is not about rounding errors, and this phrase is very common in empirical statistical testing. It is called "Testing the Null Hypothesis"

"Not statistically significant from zero (p=0.45)" means that there is a 0.55 probability that the slope is NOT zero, and a 0.45 probability that it *is*. It means your investigation/experiment failed to find strong evidence either way.

Prefiero "estadísticamente, no se diferencia significativamente de 0". El otro frase me suena un poco raro tambien..

You might also hear "was not significantly different from zero at the 5% level" (which means p=0.05).   Depending on you field, ''proof'' is considered to exist if you can make conclusions at the 5% level (usually in social sciences) or the 1% level (often in large-sample studies in medicine).

Hope this helps!

Dave


----------



## mhp

triumphraptor said:


> "Not statistically significant from zero (p=0.45)"  means that there is a 0.55 probability that the slope is NOT zero, and a 0.45 probability that it *is*.



Yes. I see that now.


----------



## Outsider

You are both right. I think the phrase they were looking for is "not *significantly* different from zero". Or, alternatively, "the difference is not statistically different from zero".


----------



## 0scar

A mi me preocupa la tradución de _average slope_ 

_La diferencia promedio/desviación media entre  3 y 12 meses no es  estadísticamente significatva (p = 0,45)/estadisticamente es de una probabilidad cercana a cero  (p=0.45) _


----------



## Outsider

Yo diría "el pendiente medio de la recta".

"El pendiente medio entre los 3 y los 12 meses no difiere significativamente de 0 (p=0,45)."


----------



## triumphraptor

Sorry to harp on about this.. but (since we're on the record and other people may look this up), there is a difference between merely significant, and *statistically* significant. The latter is not a matter of opinion. For example, there may be a statistically significant difference between the heights of oak trees in England and Spain.. but it is not significant in my view. The difference can be *extremely* small, (and thus insignificant). But if you are very sure it is not zero, it is *statistically* significant.

I've always disliked the use of the word "significant" when used with "statistically". We need a better word in English, like "distinguishable".

Politicians, and occasionally journalists (and other bad people) love to play on the confusion between these two terms. If a scientist says some effect is statistically significant, it doesn't mean that it is large or important. It simply means that it wasn't zero, with great certainty.

I scientist might say "There was a statistically significant different in depression rates between those who use the internet and those who don't". But the effect may be miniscule: the scientist may just have had a large enough sample to find the effect.  If the effect is that - say - one more person in a billion gets depressed because of their internet use....well, that's not significant in any 'normal' use of the word.

People with nefarious or unwitting motives will often take these two terms and confuse them to make some point they want to make such as: "This proves the internet is bad for you".

Many apologies for the long post - I just wanted to be sure that one of the (many) semantic shortcomings of common English usage doesn't get propagated!

gracias y lo siento Sac - yo se que esta no estaba tu pregunta!

Dave.


----------

