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4 votes
1 answer
107 views

Check if a coin flips randomly, but it can have a different number of sides each toss

I would like to check if a coin flips randomly, based on observational data. The catch is, the coin can have two sides, but also three, four, up to nine. The number of sides differs in each ...
Nucular's user avatar
  • 453
1 vote
0 answers
440 views

Compute a Monte Carlo estimate. Which of the variances (of $\hat{\theta}$ and $\hat{\theta}^{*}$) is smaller, and why?

Compute a Monte Carlo estimate $\hat{\theta}$ of $$ \theta = \int_{0}^{0.5} e^{-x} dx $$ by sampling from Uniform$(0, 0.5)$, and estimate the variance of $\hat{\theta}$. Find another Monte Carlo ...
Daniel Salinas's user avatar
1 vote
0 answers
33 views

Generate data for significance testing

I want to generate a data set with a pre-specified significance level. Let's say we have 2 covariates x1, x2, and an outcome variable y. We fit a linear regression model as follow: ...
Rasel Biswas's user avatar
1 vote
1 answer
466 views

How to interpret p-values in terms of correlation?

I have one datamatrix and a single column(let's say it fvector). I had find the spearman's correlation of each column from datamatrix with fvector i had setted the parameters as p <0.05 and i got ...
Razeun's user avatar
  • 11
2 votes
1 answer
730 views

Which statistical tests can I use to analyse significant difference between the means of non-random samples? [duplicate]

I want to compare the means of non-random samples to population mean. However, most standard tests (eg. t-tests, ANOVA, Welch test etc.) are based on the assumption that samples are randomly obtained ...
Maria Sahakyan's user avatar
2 votes
1 answer
247 views

Variable is not statistically significant in single variable linear regression but is significant in multiple regression

I had a friend ask me about this question, and I'm not 100% sure about the data she's using due to the sensitivity/privacy of the data (other than it's medical data). Sorry for not providing context, ...
Jane Sully's user avatar
  • 1,030
0 votes
1 answer
98 views

How to test the difference of two linear regression slopes with 2 independent and one dependent variable

I am trying to determine if the CO2 emissions growth rate of developing countries is higher than the growth rate of developed countries. So essentially I need to compare two linear regression slopes ...
Santiago Arellano's user avatar
2 votes
3 answers
49 views

Suitable multiple testing procedure for three very correlated phenotypes

I have ran an analysis using polygenic risk scores including genetic variants at different p-value thresholds and have the following outcomes: IQ ages 8 and 9, strengths and difficulties questionnaire ...
rkl's user avatar
  • 21
5 votes
1 answer
7k views

When to switch off the continuity correction in chisq.test function?

From this Research paper Table1 Association of RAD51-AS1 expression with clinicopathological features of EOC patients I see that p-value is calculated based on Chi-...
stack_learner's user avatar
2 votes
2 answers
4k views

Create an A/B Sample Size Calculator using Evan Miller's Post

To learn more about A/B Testing sample sizes selection I am attempting to use Evan Miller's popular blog-post to recreate a sample size calculator (https://www.evanmiller.org/sequential-ab-testing....
sczopek's user avatar
  • 31
0 votes
1 answer
264 views

What is the analytical test to run in case of 1 measure for three groups?

I have this case where the data look like that Trial Person 1 person 2 1 4.7. 3.8 2 7.1. 6.3 3 5.4. 4.5 I want ...
Omar113's user avatar
  • 232
2 votes
0 answers
529 views

Are there any quantitative metrics for how representative a sample is?

I'm interested in selecting a sample that is representative of a population. Additionally, I want to be able to quantitatively measure the representativeness of a sample. For example, is there a way ...
Tunk's user avatar
  • 151
1 vote
1 answer
23 views

2 Independent, 1 Dependent Analysis through SAS. Should I create a surface?

I have 12 runs of thermal data that each generate a matrix. I've added noise to my systematic data to simulate my detector. My output for each of these is a 500x500 matrix where the vertical axis is ...
TallnGinger's user avatar
0 votes
1 answer
40 views

Understanding the meaning of random when working with measures repeated at time=1,2,3,4

This stems from a recent exercise in an undergrad course, where we measured average resting heart rate(fH), and fH while holding breath of durations between 0-20s,20-40s,40-60s, etc. Not only could ...
Jacob Nowatzke's user avatar
2 votes
1 answer
13k views

how to calculate fold change when we have replicate

I have obtained genes with ratios. As an small example you can see my data below ...
Nik Bernou's user avatar
1 vote
1 answer
493 views

how to find similarity based on only one column value

I am not sure if it is possible and that is why I am asking the question here. I have a data looks like below ...
nik's user avatar
  • 105
2 votes
2 answers
1k views

The value of an Effect Size

I calculated a Cohen's d value of d= -2.1. I understand that there are small, medium, and large effect sizes. But in my case the d value is negative? Would it still be considered large since abs(-2.1)...
HM_7's user avatar
  • 46
0 votes
1 answer
48 views

What tests to analyze the following hypotheses with nominal data?

I have a set of questionnaire data to analyze the working culture for respondents. (There are four existing cultures; a,b,c and d) Variables including Gender, Organization, Public/Private Sector, ...
user108297's user avatar
3 votes
0 answers
530 views

Is this simple paired-sample permutation test valid?

I have about 10 pairs of scores, $(x_1, y_1),~ ...,~(x_{10}, y_{10})$, with all $x_i$ and $y_i$ being between 0.0 and 1.0. I'm interested in testing whether the mean difference over pairs is ...
rd11's user avatar
  • 179
2 votes
0 answers
396 views

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: ...
Mark Ramotowski's user avatar
1 vote
0 answers
46 views

Sample size when using GPS-trackers to analyze movement of reindeers

If one were to try and analyze the movement of ~2 500 reindeers before and after a (man-made) change in landscape have occured. Specifically how spread out the herd is, both as a whole and if there ...
Druleful's user avatar
2 votes
2 answers
786 views

Test for statistical significance in performance variability

I'm analysing data collected from a call centre activity in which agents are calling prospective leads. For each call made, if the lead coverts the call is a success and if the lead does not convert ...
RDJ's user avatar
  • 535
2 votes
0 answers
846 views

How would I determine statistical significance for ad impressions?

I'm programatically adding keywords to bid on. Some keywords will trigger ads and impressions, and some impressions will trigger clicks. Clicks / impressions = CTR (click-through-rate). Clicks cost. ...
Chloe's user avatar
  • 267
1 vote
2 answers
868 views

Compare lists of genes

I have two lists of differentially expressed genes: the list 1 was derived from the universe A of total genes while the list 2 was derived from the universe B of total genes. A number of genes is in ...
NewUsr_stat's user avatar
5 votes
2 answers
2k views

Testing if distribution is similar between two groups

I have a variable young that is equal to 1 if a participant is less than 25 years old. I then have a list of of each participant'...
LF12's user avatar
  • 539
1 vote
1 answer
88 views

What statistical analysis should I use for my study?

In my psych class we were testing to see if groups of men or groups of women would be more helpful in an emergency situation (we are testing for the bystander effect), and we are testing to see if ...
sophia's user avatar
  • 11
2 votes
1 answer
1k views

When is appropriate to combine two treatment groups from one study into a composite whole for a meta-analysis?

The treatment groups I would like to combine appear to be virtually the same, at least by generic label for each group, e.g., groups with the same treatment but implemented at different sites or ...
Angie's user avatar
  • 21
0 votes
2 answers
12k views

Comparison between Two Groups

One of my demographic variable is age. Age is measured as continues data not categorical. If I want to test differences between two groups to determine whether there is significant difference between ...
Kanaan's user avatar
  • 3
8 votes
2 answers
10k views

How to statistically compare two algorithms across three datasets in feature selection and classification?

Problem background: As part of my research, I have written two algorithms that can select a set of features from a data set (gene expression data from cancer patients). These features are then tested ...
revolusions's user avatar
-1 votes
1 answer
750 views

How to provide statistical evidence that an experimental method is providing higher mean percentages?

I performed an experiment using two different methods. The data are percentages and higher percentages indicate a better method. The results were as follows: ...
conarch's user avatar
  • 11
1 vote
0 answers
288 views

Dixon test for outlier but which one is an outlier?

Following my previous question, I used Dixon test for outliers with the help of Michael Chernick answer. So now I have pvalues for say 10 numbers (basically 10 patients). But I have around 50k pvalues ...
Vikas's user avatar
  • 227