Statistical significance refers to the probability that, if, in the population from which this sample were drawn the true effect were 0 (or some hypothesized value) a test statistic as extreme or more extreme than the one gotten in the sample could have occurred.

learn more… | top users | synonyms (2)

2
votes
0answers
16 views

pvalues of glm coefficients and heavy tailed distributed residuals

I've seen this post but I have still some additional questions. I have a glm model with a continous response and a couple of hunderd predictors (which represents different conditions). I want to know ...
2
votes
2answers
121 views

How to check statistical significance

I am not at all good in statistics and totally new here. My doubt may be very simple or foolish, please don't mind. I am from Civil Engineering background. In an experimental work, I am comparing ...
0
votes
2answers
57 views

Which statistical test to look for performance difference in two samples? [on hold]

I am trying to find if there is any difference in performance between two sampled groups. ...
0
votes
0answers
34 views

Which statistical test to use on mean data?

I have sets of data from two sample A and B. the data in sample A and B are the average mean of the population sample. Examle, sample A has list of data. each data in he sample is a an average value ...
0
votes
0answers
7 views

How do I test whether there is a deviation in mutual fund investor strategy depending on movement of market indices, etc?

Im fairly new to the world of statistics and econometrics. I have done a years worth of study for both in the UoL international program. Im working on a project this summer to see whether the ...
0
votes
0answers
32 views

Which statistical test should I use for my report which has Two sets of data?

I have collected data from load testing a website. The basic Idea here is that, a website hosting on a server is tested by increasing number of virtual users. Example, there are 5 iterations in each ...
1
vote
0answers
18 views

suitable statistics to replace box plot [on hold]

I am applying few classification methods on a set of images. Currently, I have experimental results in box-plots and want some statistical method to report them in my dissertation. Problem ...
1
vote
0answers
24 views

How do you test if there is a statistically significant change in variance using dependent variarables?

Given a group of subjects and a value measured across a baseline period and a measure period, how do I test if the spread of the data is statistically significantly different?
0
votes
0answers
18 views

Insignificant slope coefficients

While calculating the value of the dependent variable why do we take into account even the variable whose slope coefficients were not significantly different than zero? Is my understanding correct ...
3
votes
1answer
58 views

Most accepted theory to analyse trend in data series

I have pollutant concentration for long period I want to determine trend. I have read some of the question answers in this blog regarding same . I have few queries. What is most accepted theory to ...
2
votes
0answers
23 views

Dvoretzky–Kiefer–Wolfowitz inequality hold for discrete distributions?

I am wondering whether Dvoretzky–Kiefer–Wolfowitz inequality holds for discrete distributions? Any comments or references would be greatly appreciated.
1
vote
0answers
11 views

Significance level in terms of modeling error

Let's imagine I have a regression model with numeric output or a binary classification model with probability output (probability of a sample to belong to class 1). I predict values for pairs $A_1$ ...
0
votes
0answers
9 views

How to calculate the probability of a sample to get a specific pattern, given all samples and features?

I have a data aggregation tool, which collects information on many samples (clusters of molecules in this case). So it can create a sparse matrix of NxM binary values (N answers of 0 or 1 for M ...
2
votes
0answers
13 views

Why would standardized betas be high (e.g. .66) but non-significant in moderated regression?

Running a moderated regression using PROCESS macro in SPSS (issue replicated by running the same moderation using mean-centered variables in SPSS linear regression command box), I am finding that the ...
1
vote
0answers
27 views

Classifying groups using statistical significance

I am really struggling to get my head around some sample questions of my quant class. The exam is looming and I cant grasp what must be a basic concept. Sample A service provider has identified ...
0
votes
0answers
13 views

Indicator regressions: standard errors

Hi I am estimating a regression of Y on X where both Y and X are indicator variables, that is, they take values 1 or 0. The model is $Y=\beta*X+\epsilon$ (without constant). I use OLS to estimate the ...
0
votes
0answers
14 views

Estimating treatment effects on unequal groups

The setup is quasi-experimental: treatment and control groups, chosen ahead of time, are given a pre-test and a post-test. They are close to equal in size, and while membership was selected based on ...
0
votes
0answers
9 views

ANCOVA model with non-significant variables performs better?

I'm running an ANCOVA test with 2 dichotomus and 1 ordinal variable as fixed factors and 2 continuous variables as covariates. I was advised to remove any non significant factors because with them ...
0
votes
0answers
11 views

Interpretation of non-significant parameters in significant Cox-model as prognostic factors

I want to analyze predictive factors for patient survival after surgery. I have variables that are based on investigations at the time of the surgery, known predictive factors (age, KPS) and data on ...
0
votes
1answer
30 views

Statistical test for classification models

I have 3 models from which, for each model, I train a classifier and then evaluate it, currently using stratified 10-fold cross validation and then take the mean accuracy ratio of these from each ...
1
vote
0answers
19 views

What to display for differences of medians of discrete variables?

I am using the Mann-Withney U test to compare two samples of count data. In several situations, I find that there is a significant difference between the populations, but when I estimate the CI for ...
0
votes
1answer
22 views

Is it common practice to correct for multiple comparisons with multiple ANOVAs?

I gave three groups of participants (say groups A, B, and C) different treatments, then gave all groups the same questionnaire. The questionnaire has ~50 questions. I then run ANOVA on each of the ...
7
votes
2answers
123 views

Aside from Durbin-Watson, what hypothesis tests can produce inconclusive results?

The Durbin-Watson test statistic can lie in an inconclusive region, where it is not possible either to reject or fail to reject the null hypothesis (in this case, of zero autocorrelation). What other ...
0
votes
1answer
22 views

Confidence intervals for percentage share of multiple response

If I have a sample of 100, who give responses to a set of multiple response variables, say for example, the brands they have purchased in the last 12 months. How can I calculate the confidence ...
1
vote
2answers
51 views

Comparing frequencies

I'm trying to find the right test to use to compare 3 frequencies. Basically, in my research, 3 separate user interface prototypes were given to the same sample (10 people) and particular tasks needed ...
2
votes
0answers
24 views

Position Based statistics in DNA sequence

Let's say you have a DNA sequence with 21 positions, each of which can have one of four nucleotides (A,C,G,T). For example, If I see lot of C's and G's (called 'GC content') at 19th position in all ...
4
votes
2answers
28 views

Help find a statistical test for proportion of a binary outcome with repeated measures

Here is an illustration of my problem: I have two stimuli (A and B) given to a number of subjects. Each subject is sequentially subjected to both stimuli 5 times (AAAAABBBBB or BBBBBAAAAA, but not ...
2
votes
1answer
30 views

Bonferroni Correction for Post Hoc Analysis in ANOVA & Regression

As we know, if we are doing many tests or multiple comparison, we don't use the same $\alpha$ value and use some $\alpha$ correction methods like Bonferroni. This is done because when we do multiple ...
1
vote
0answers
25 views

Likelihood of burning for a type of vegetation - which test to use?

I have six categories of vegetation, their total surface and the percentage of surface that has burned. I want to say eg. "coniferous vegetation burns more often on a statistically significant level". ...
2
votes
0answers
35 views

Statistical Significance?

I'm wondering if there is some sort of statistical significance test that would suit my data, or whether I have to depend solely on descriptive statistics. Here's what I've got: Thirty six students ...
1
vote
1answer
42 views

Proving similarity between two rankings

We are seeking a comparison of two different rankings of the same 3 systems Background: We have conducted a test of 3 different systems. Participants experienced a system and rated it on a 7-point ...
0
votes
0answers
8 views

Interpreting a significant interaction with only 1 out of 3 dummy variables (arising from same categorical variable)?

I'm running logistic regression analyses (paired observations - we cluster on ID code (=xtlogit in STATA)) with: dependent variable: trust (0/1). independent variable: - eye pictures ...
0
votes
0answers
34 views

Efficient statistical test to compare two multivariate distributions

I am looking for a test to assert the "equality" of two multivariate discrete distributions, $\mathbf{A}=\{A_1,\dots,A_k\}$ and $\mathbf{B}=\{B_1,\dots,B_k\}$ for which I do observe two samples ...
1
vote
0answers
31 views

Two dimensional Kolmogorov-Smirnov test

For a one dimensional Kolmogorov-Smirnov test there is a theoretical result, one can compare his or her test results directly by theoretical one, which is infinite sum (notice this formula is for big ...
0
votes
0answers
4 views

Test statistics for MAPE

I am working with longitudinal panel data where I use variables of the first panel wave as training data in a regression to predict the consecutive waves. To compare different prediction approaches I ...
4
votes
2answers
40 views

Appropriate visualization for the Wilcoxon signed rank test

I have question regarding the Wilcoxon test and if the results can be represented visually. I had 10 participants in my experiment where by I asked participants to read sentences and then they ...
0
votes
0answers
18 views

Intuition behind Whites reality check

Assume you mined some strategy following a simple rule based approach with positive performance measures over the last 30 years from a giant parameter space. Now you want to find out how likely it is ...
0
votes
0answers
15 views

Chi-square and subsequent comparisons

I have the following dataset and would like to find out firstly if I'm using the correct tests. The data are hospital admissions data for cause X and admissions data for all admissions. If an ...
0
votes
1answer
35 views

Is my Interpretation of this statistical distribution correct? [closed]

The torque of shld flx action was between 8Nm to 10NM for 10% of the time Is my interpretation correct? If so how do I determine torque for one of the 19 activities?
0
votes
0answers
22 views

How would I calculate the t-statistic for this data and then determine if it's significant?

Say we want to test the hypothesis that a control group of cancer patients would report higher mean pain ratings than an experimental group receiving special massage treatments. Group 1: Mean = 78.1 ...
3
votes
1answer
64 views

How to analyze if only N and means are available?

I have data on following experiment: Sample taken from each of 5 normals and 5 patients All normal samples are pooled and mixed together. Similarly all patient samples are also mixed ...
0
votes
0answers
11 views

Is there a way to determine if commonalities between two sets are significant?

I have two sets of genes that I want to compare, and I'm wondering whether the common members between the two sets are significant. Is there a way to derive a p-value to deem the common set to be ...
3
votes
1answer
26 views

Calculate Significance between samples with skewed data

Background: I have a sample that is very left skewed. The mean of this sample is 4.01 (min = 1, max = 5). I would like to know whether or not a subset of this sample is significantly different than ...
0
votes
1answer
86 views

When is Variance Statistically Significant?

This may seem like a rudimentary question relative to other posts, but how do I determine whether the variance is statistically significant? For example, let's say I have a population of 10000. I ...
0
votes
0answers
16 views

Losing power by doing repeated measure instead of standard anova

I have an experiment with one within subjects factor. It has 3 levels: sleep deprived (24 hours), sleep deprived (12 hours), not sleep deprived. Over the course of 6 weeks we run a counterbalanced ...
0
votes
0answers
11 views

Manufacturing Process Validation - Sample size calculation

I am new to manufacturing process. Can someone help me to determine the sample size required to perform Manufacturing Process Validation? I know nothing about six sigma, so simple answers are highly ...
5
votes
1answer
45 views

Is it possible to calculate Q1, Median, Q3, StDev from already aggregated data?

We have data that will get aggregated per hour into the following values Q1 Median Mean Q3 Standard Deviation Max Min Count of Values So the data will look more or like this in the end. ...
0
votes
0answers
10 views

Results from petest do not match documentation

I am trying to use the petest function in R (http://www.inside-r.org/packages/cran/lmtest/docs/petest) to decide between a log or a linear model. The documentation, and the referred textbook, both ...
1
vote
0answers
41 views

How to show whether a hypothesis is true or not

I have the following hypothesis: "The higher the number of translation-stable words between a pair of countries, the higher the correlation between the happiness scores of their words". note: ...
2
votes
2answers
72 views

Example of interpretation of logistic regression

I was looking at a paper by Pell JS 2009, regarding smoking and survival following acute coronary syndrome. Part of the analysis carried out in the paper was a logistic regression with results as ...