All Questions
Tagged with statistical-significance chi-squared-test
104 questions with no upvoted or accepted answers
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Is 'Significance test for Lasso' justified?
Lockhart et al described a "Significance test for the lasso", the motivating example for which is forward variable selection in a linear regression. In their Figures 1 and 2 they show Q-Q plots of a ...
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21k
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Comparing two percentages
How would I go about comparing two percentage figures from two different sample sizes? For example:
Sample 1 - 10% (220,510 out of 2,205,100) of respondents answered "yes",
Sample 2 - 31% (12 out ...
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4
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2k
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Z-Test Versus Chi-Square Test
I need to test whether response rate for Test B is larger than response Rate for Test A (i.e. AB Test).
Null Hypothesis: is Response Rate (Test B) <> Response Rate (Test A).
Alternative ...
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3
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50
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Question about using the chi-square test on an astronaut dataset to determine if over 1000 hours in space and early mortality are related
I am analyzing an astronaut dataset to try and determine if a high number of hours flown in space (>1000) by an astronaut is related to premature death (which I defined as dying before the age of ...
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3
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4
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Is there an association between the work status of the college students and the challenges facing them?
So I am supposed to do a study about the online learning obstacles. now the research question is as stated as follows:"Is there an association between the work status of the college students and ...
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Chi-square test vs. McNemar's test - which test is right for this highly usual situation?
Here is, I would assume, a fairly common situation: I would like to know which test to use to assess whether the tendency to answer "Yes" on question 1 of a questionnaire is associated with ...
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3
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1
answer
547
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Chi-square test with replicate nested
I have a question about how to analyse count data with replicates nested in each treatment. For example, imagine temperature can influence the sex ratio of mosquito larva emerged from eggs. I have two ...
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2
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128
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Post hoc after a 2xN chi-squared test
I have two groups of people, and I want to determine if there's a significant difference based on their language. My data consist of word frequencies (how many times a person sayed a given word in a ...
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79
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global significance of glm model
I am a beginner regarding GLMs and R. I have built the following glm model:
...
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2
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62
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Statistical Significance of a Comparison of Percentages
I'm looking at a comparison of percentages pre/during covid and I'm trying to work out how to show if there is a statistical difference between groups. I'm not sure which statistical test to use and/...
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2
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Which statistical test for two group proportions over two time periods? 100% sampling, capped membership. Independent groups over time
I'm comparing the number of male and female hires at a city in the 1980's to the number of male and female hires in the 1990's. I'm looking for whether the percentage of females increased ...
user252085
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Sample size estimation with known mean (optimal value), unknown stdv
quick question on sample size estimation. Let's say i play a game of poker, where i have 2 options, play or don't play. In the long run, the optimal strategy is to play 15% of all times, dependent on ...
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2
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46
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Statistical test for comparing cutoff values in independent samples
A binary diagnostic test currently uses the same cutoff value (level of biomarker) for males and females when determining disease vs non-disease (D+/D-). However, I suspect that the level of biomarker ...
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2
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357
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Statistical Significance of the "Cost per Conversion"
I am trying to optimize our AdWords ads and running some statistical tests. I use a chi-squared test and Fisher's exact test for conversion rate data; for example the click-through-rate (CTR) or the ...
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Cross-tabs: Can residuals in table be interpreted if chi-square statistic not significant?
I'm examining a series of 2 x 5 cross-tabs / contingency tables. I have taken the approach of: (1) determining whether the chi-square statistic (test of independence) is significant (i.e., p < .05),...
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371
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Testing for a significant difference between 2 groups
Question 1
Two equally sized patches of the night sky are examined:
Patch A contains $100$ stars
Patch B contains $110$ stars
Is there a significant difference between these two patches of night ...
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2
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1
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696
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How do I test for differences in cost per acquisition (CPA) in an A/B test?
How would I go about testing for differences in cost per acquisition (CPA) in an A/B test?
I'm a huge novice and am unsure if I would use some kind of t-test or chi-square test (or neither) to ...
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2
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1
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How to choose good data to avoid a useless Chi Squared test?
In this video, Khan Academy is teaching Chi Squared test with an example: https://www.youtube.com/watch?v=hpWdDmgsIRE
Given 3 medicine, $herb_1$, $herb_2$, and $placebo$, we give these to 3 different ...
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396
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Calculating the Chi Squared from combinations of subgroups
Let's say I can calculate the chi squared p-value of different categorical variables and summarise them into a table like so:
Initial Data:
...
- 539
2
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0
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37
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Comparing means of two samples, one with 2million+ samples, other with only 200
I have two sets of data and a metric associated with each of them, I want to see if one category of data (e.g. males) have a tendency to have ahigher metric associated with it than the other category (...
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A/B Testing (Pearson Ch-Square Test) with Unequal Sample Sizes
We have run A/B tests in the past using a 50/50 split, and have used the power prop function for calculating the sample size using the power.prop.test in R. My question is how do I calculate what my ...
2
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Visualise significant differences in a contingency table?
I'm working with pandas and scipy, and I would like to find a quick way to visualise unusual values in a contingency table.
Say this is my contingency table:
...
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2
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79
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How to test for a home bias in a data set?
I'm trying to think how I can test a data set I have, for transactions between buyers and sellers, for a home bias. My hypothesis is that buyers would rather buy from a merchant from their home ...
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277
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significance test to use for multiple conversions in an A/B test
What is the proper way to measure significance in an A/B test, when a visitor can potentially "convert" more than once?
I understand a chi-square test or z-test are most often used for A/B testing, ...
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1
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0
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How to statistically validate samplers? Is Chi-Square test relevant for synthetic data?
I am developing sampling procedures for different kinds of discrete objects (rankings, sets, etc.). In most cases I know the theoretical distribution of the objects I'm sampling. My idea is thus to ...
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Correct statistical test to model user preferences among multiple models
My problem involves comparing the performance of machine learning models to how good each model's recommendation is.
The way I'll design the experiment is as follows:
I'll send out a form to multiple ...
1
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0
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51
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How do I determine which events occurred significantly more during a certain operating mode?
I have data of $N$ different event $E_n$ occurring at times $t_{n,i}$. So any event $E_n$ could have occurred any number of times.
Normally the system operates in operating mode A. Sometimes the ...
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1
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1
answer
47
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Hypothesis testing: formulation and rejection
Suppose I want to compare a book A with a book B to see if a particular word occurs significantly more or less often in either book. If I use the chi-square test (α = 0.05, one degree of freedom, ...
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1
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189
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Calculating Critical Value for Mixture of Two Chi-Square Distributions
Let's say I have a statistic X which is distributed as a mixture of two chi-square distributions; $$X \sim 0.5\chi^2_1 + 0.5\chi^2_2.$$
I'm wondering how I can calculate the critical value(and p-value)...
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Test to determine if difference in revenue percentage is significant between days of week
I work with data for a mobile app and the analytics system records the dollar sum of user purchases made on each day. My task is to determine whether there is any statistically significant difference ...
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1k
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Bootstrap method for chi squared test of independence
I really need some advice about using the chi-squared test of independence.
I want to use the bootstrap-chi-squared method for conditional independence testing. The problem is that the DOF is really ...
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1
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1
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Multiple Hypothesis Tests - Chi Square
I want to write a method to test multiple hypothesese for a pair of schools . I want to consider all possible pairs of words (Research Thesis Proposal AI Analytics), and test the hypothesis that ...
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1
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78
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How to check for a biased/irregular number of occurrences of a given pattern in a sequence of numbers?
As a heads up, my knowledge of statistics and probability is minimal at best but I need help on something for an application I’m building.
Ok I have a sequence of values either 0 or 1 that might look ...
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Proper Test for Type of Data
Warning: I have not done any statistical analysis since 2012.
Problem: I have a list of lists of lists: Each of the $289$ ($17\times 17$) element is $\{\phi_{j,1},\phi_{j,2},f(\phi_{j,1},\phi_{j,2}),\{...
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508
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Difference between Chi^2, Chi^2/dof and R^2
I have radioactive decay experiment (so the model is y = Ae^(-kt)) results and am (slowly) teaching myself mathematica to plot this. I want to output some measure for the goodness of fit, but am ...
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Testing for potential discrimination
Apologies, I know this is incredibly simple but it's been a while since I was in school!
I'd like to run a significance test on the (dummy) data in the table attached to ascertain whether there has ...
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1
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0
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Significance of single classification change across multiple time slices (archaeology)
I'm trying to determine if I'm correctly testing for significance of the change in artifact type presence across several time periods.
In an archaeological survey, stone tool artifacts were cataloged ...
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Why can chi squared not be used when the two variables are measured with means?
I am taking an introductory to statistics class and I have found most of it to be pretty easy, but there is one thing I do not quite understand. The problem is given like this: There are two different ...
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significantly more down-regulated genes than up-regulated genes
I would like to test if my dataset has significantly more down-regulated genes than up-regulated genes.
In my set of significant genes (BH-corrected) I have 20 up-regulated genes and 69 down-...
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Are there any assumptions about row/column margins in a chi2 test?
I just learned that most tests of associations on 2x2 tables have assumptions about row and column margins being fixed or not.
Is there any similar assumption when it comes to chi2 tests? Can I do ...
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What statistical test could I use to compare categories of two data sets (for enrichment) with hugely different sample size?
I have some biological variant effect prediction data. This data can be split into categories based on the biological effect each variant has. I've turned this into two data sets: One is the "full" ...
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What kind of test of significance can I use on ordinal data?
I have several variables that consist of ordinal categories (i.e. no fruit consumption, 1 portion a day, 2 portions, etc.) and I would like to test whether they differ significantly with respect to a ...
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Can you do chi-square test of independence on quantized continuous random variables?
Say I have a sample with m observations, each observation has two features X and Y which are continuous random variables. I'm interested in knowing if you can bin X and Y each into N quantiles, ...
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Problem of Critical Region and Significance Level (Statistics)
An investment adviser states that the risk (standard deviation) when investing in a certain instrument is greater than $3.$ To corroborate the validity of this statement, he plans to realize: $H_0: \...
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1k
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Fisher's exact / Chi-squared tests with repeated/dependent observations
I have a dataset (structure explained below) for which I want to perform some tests on 2x2-tables.
The data is generated from a (randomized) experiment, and structured as follows:
I have n subjects, ...
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Test for positional amino acid enrichment
I have a question about which statistical test to use for a particular research question. I am studying protein binding motifs (amino acid sequences that other proteins bind to), typically these ...
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Independence on only some cells of the contingency table
I have two discrete variables with three values each, A,B, and C for one, and D,E, and F, for the other (for around 500 objects).
I am only interested to reject independence in three cells of the ...
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Chi Test to compare the volume distributions of 2 samples
I have 2 samples and i want to check whether their distributions are similar (or not).
The samples are distributed in the following way (they are banded into 'scores'):
How do i check the whether ...
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207
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Help with preference test
I need some help choosing the statistical test to calculate if the bee families have a preference for a straw size.
To summarize the project, I am looking at 4 bee families
Osmia-Megachile-...
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79
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coincide by more than chance?
I have an issue where I want to see if two events may coincide by more than chance.
For instance given the following data I may hypothesise that "Alice" and "Bob" come into the office together more ...
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