Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [statistical-significance]

Statistical significance is a characteristic of a statistic viewed in light of a null hypothesis and a given significance level. It reflects whether the statistic belongs to the rejection region (is statistically significant) or the acceptance region (is not statistically significant).

Statistical significance is a characteristic of a statistic viewed in light of an (implicit or explicit) null hypothesis and a given significance level. It reflects whether the statistic belongs to the rejection region or the acceptance region defined by the null hypothesis and the significance level. The statistic is then statistically significant or not statistically significant, respectively.

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Statistical test to tell whether two samples are pulled from the same population?

Let's say I have two samples. If I want to tell whether they are pulled from different populations, I can run a t-test. But let's say I want to test whether the samples are from the same population. How does one do this? That is, how do I calculate…
user1566200
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Interpretation of non-significant results as "trends"

Recently, two different co-workers have used a kind of argument about differences between conditions that seems incorrect to me. Both of these co-workers use statistics, but they are not statisticians. I am a novice in statistics. In both cases, I…
amdex
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Convention for symbols indicating statistical significance?

This question might probably also fit into Academia.SX. I'm writing my first paper in life sciences and I'm very often seeing asterisks as indicators for statistical significance (*). I'm wondering if there's a convention on which symbol, and how…
Eekhoorn
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How do I calculate if the degree of overlap between two lists is significant?

If I have two lists A and B, both of which are subsets of a much larger list C, how can I determine if the degree of overlap of A and B is greater than I would expect by chance? Should I just randomly select elements from C of the same lengths as…
Stew
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Could it be shown statistically that cars are used as murder weapons?

I heard a story recently in which someone said if they wanted to kill somebody (and get away with it) they would do it with their car. They cited various statistics about the number of auto-related deaths (including car-on-pedestrians) coupled with…
sfletche
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Practical vs Statistical significance

In a nutshell, what would be the main differences between practical and statistical significance? What would be the relative importance of each in drawing scientific inferences, for example?
pkg77x7
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Olympics - Hungary Has Double Digit Lead in Gold? (Population Relative)

I created a Web page that pulls in live Olympic medal results from Thompson Reuters and worldwide population counts from the CIA. The results are interesting to me - Hungary has a double digit lead in gold medals over the rest of the world. Also,…
Ronnie Royston
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Can you say that you reject the null at the 95% level?

I know that you reject the null at the 5% significance level. But I read someone writing that they reject at the 95% level. I assume the confidence level. But can you technically say that?
Hans Brecker
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Is it ever good to increase significance level?

Suppose you are using $\alpha = 0.01$ as the significance level. IF you are not getting significant results, is it better to increase the significance level to $\alpha = 0.05$?
Thomy Ja
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A Stats 101 question with a real world application

This is probably a far too basic question for this board - but on the other hand, I know I'll get good answers. "Stats 101" is a metaphor, by the way. I'm asking for help with my work, not my homework! I am looking at aggregate financial data for…
Vince Kueter
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Statistical Significance of a Subset

I have looked around and haven't been able to find an answer to this question. Seems like an easy question, so maybe it's just a matter of looking in the wrong place. I have a data set representing performance of assets across a large region. The…
Kevin Presley
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Is statistical insignificance fatal?

I apologize if this question has been done to death, but as a non-statistician I really don't know what is the bottom line takeaway. I am looking at a sample of 30,000 individuals who were the subject of an economic intervention. This intervention…
tom russell
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Statistically significant difference

I am reading a medical paper, where it says: There was a statistically significant improvement in dyspnea in the IPC group at 6 months, with a mean difference in VAS score between the IPC group and the talc group of −14.0 mm (95% CI, −25.2 to −2.8…
STRICKLAND_7
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Real world performance of p<0.005 compared with 0.05

Within scientific literature, there is a tentative proposal to change the significance level from p=0.05 to p=0.005 http://www.nature.com/articles/s41562-017-0189-z I understand there is a lot of nuance to this proposal and don't necessarily want to…
conor rochford
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Statistical test to compare two ratios from two independent models

What statistical test can I use to compare two ratios from two independent samples. The ratios are after to before results. I need to compare the after/before ratios for two independent models and show whether they are have significant difference or…
pom
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