Hypothesis testing assesses whether data support a given hypothesis rather than being an effect of random fluctuations or some other process described by an alternative hypothesis.

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What is the intuition for dependence assumption in Benjamini and Hochberg (1995)?

For dealing with multiple testing, Benjamini and Hochberg (1995) assume that the tests are independent. Benjamini and Yekutieli (2001) show that (1) the 1995 result also holds under (I think) weaker ...
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Multiple comparisons on nested subsets of data for a non-parametric test

My problem: I'm using data sets where some are nested in a non-parametric test that expects independent data sets. How can I correct for that in a way that is reasonable? Or even better: What would ...
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19 views

Testing if points on a line are over/under dispersed

I have a series of about 1000 points on a chromosome and I want to know if they are clumped, over-dispersed, or neither. The chromosome can be viewed as a 1-dimensional. I've looked over some ...
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29 views

Point hypothesis and equivalence hypothesis at once

Sometimes researchers (especially in collaborations) have two opposite but sound theories: There is a difference between two groups or there is only negligible difference. Now they ask their ...
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15 views

What can I do to if I have a nominal dependent variable and scale independent variables?

Our dependent variable is a nominal variable that asks respondents "would you share this video?" with the responses being either yes or no. The hypotheses we are testing are all relational directional ...
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8 views

How To Determine Association Plot in R and p-value

I have created a contingency table and an association plot in R and I am not quite sure how to interpret it. Here is my contingency table: ...
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13 views

Statistical test Comparison of

I have some ordinal data (no. of exits from opiate treatment, by type (planned unplanned exits etc.). I want to know if last years figures have a statistical probability of being different from ...
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23 views

Compare two small groups (population vs sample) over time

I am studying banks behaviour according to 6 financial rations throughout a 3-years period. I have 32 observations separated into two groups: large (6) and medium-sized banks (26). However, since in ...
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How to compare 4 independent means when there is no dependent variable?

There is one other question similar to mine (Compare independent numeric vectors (means) in R), but has not been answered (1 year has passed), so I'm repeating the question here. I have obtained exam ...
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31 views

AB testing vs testing the null hypothesis

I'm trying to understand the difference between testing the null hypothesis (i.e. testing that the probability of a "goal" is the same across 2 different populations, similar to prop.test in R) an ...
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2answers
115 views

Why am I getting inconsistent results from Wilcoxon signed rank test and Kruskal-Wallis test?

I am doing a study on 3 drugs, comparing response pre-post treatment. My objective is to know if these drugs are effective and which one is better. I used non parametric tests since the results ...
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69 views

Can Mann-Whitney test be used for post-hoc comparisons after Kruskal-Wallis?

I have a simulation where an animal is placed in a hostile environment and timed to see how long it can survive using some approach to survival. There are three approaches it can use to survive. I ran ...
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15 views

Difference test for beta–binomial variables

Let $X \sim \textrm{Beta–Binomial}(\alpha_1, \beta_1, n)$ and $Y \sim \textrm{Beta–Binomial}(\alpha_2, \beta_2, n)$ and write $\mu_1 = \frac{\alpha_1}{\alpha_1 + \beta_1}$, $\phi_1 = \alpha_1 ...
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31 views

How to Test if the Difference between Two Means from Different Samples are Significant?

here are distributions of four samples: and the following is the table of data: I would like to test: (1) if the difference between means of "Give" and "Work-Give" samples is significant; and (2) ...
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35 views

Hypothesis Testing using dichotomous and 7-point Likert scale

I am working on testing the following hypothesis: H1: People who are worried about their health will consume yogurt H0: People who are worried about their health will not consume yogurt I have ...
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50 views

How can I test if there is a correlation between a score and a likert scale?

I'm having difficulty finding out what I can do with my data set. It comes from a french reading test that have 30 multiple choice questions. For each of these questions: I have the facility value ...
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65 views

MHT: Pre-Selecting statistical tests without Bias

Summary: The last formula boxed in red (which is a modified log likelihood from logistic regression) is a special non-differentiable loss function that is adapted to contain a Bonferroni correction in ...
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1answer
25 views

Multiple hypothesis testing with FDR in R - FDRtool and p.adjust

i am very new to this field, so please bear with me. I have 600 parameters, on which i perform simple pairwise x,y correlations.For adjustment of the p-values ive been stuck between two R-packages. ...
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3answers
130 views

Should I use t-test on highly skewed and discrete data?

I have samples from a highly skewed dataset about users' participation (e.g.: number of posts), that have different sizes (but not less than 200) and I want to compare their mean. For that, I'm using ...
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21 views

Statistical tests

Can someone please explain the difference between difference test and correlation test? I am confused because e.g. if a mean of one group (males) is significantly different from the other (females), ...
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Comparing transaction counts between samples

I have a treatment group and two control groups for customers and the count of their transactions: ...
2
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1answer
42 views

Wald test and Type III test don't agree?

I am having trouble understanding the output here. In the green table, it seems like SAS is saying "Gender F" and "Gender M" are not significant. However, in the blue table, seems like it's saying ...
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4answers
263 views

How exactly does null hypothesis testing work

I'm trying to gain a better understanding of how null hypothesis testing works. I have 3 questions related to the code below: Am I right in saying the probability of each t value in ...
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26 views

Multiple Sample Equality-of-Distributions Test For Panel Data

Suppose I have repeated time observations for 800 meter sprint for a group of athletes over the course of a season. I would like to test the hypothesis that all the times are drawn from the same ...
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1answer
48 views

Difference of means when population mean is known?

I’ve approached a unique problem, and I want to make sure that I am going about the test that I am running in the correct way. Here’s a brief background: The goal of this project is to automate an ...
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how to test if a proportion of alleles is different between conditions?

I am in doubt about which type of test I could performed on my data. I have a data frame of the following type: contig, pos, A1, A2, Ctrl_A1, Ctrl_A2, Treat_A1, Treat_A2 comp1293557_c0_seq1, 284, ...
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26 views

Rank of a matrix in regression hypothesis test?

In going over some example problems from class notes, I came across the following problem: "Suppose we have a regression model $y=\beta_0+\beta_1x_1+\beta_2x_2+\beta_3x_4+\beta_4x_4+\epsilon$. We ...
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17 views

Interpreting the Johansen cointegration test output

I am running the Johansen cointegration test using 2 non-stationary time-series, as suggested by the literature. The output I got is the following: ...
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14 views

What is the procedure to compare two different period time series

I am currently working on the task that I would like to compare two different period time series like Sales in 2012 vs Sales in 2013. Kindly suggest me any statistical procedure.
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648 views

Should I use t-test on highly skewed data ? Scientific proof, please?

I have samples from a highly skewed (looking like an exponential distribution) dataset about users' participation (e.g.: number of posts), that have different sizes (but not less than 200) and I want ...
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2answers
38 views

Likelihood ratio test to determine if average number of accidents has dropped?

I can't find any worked (non-trivial) practical example for a likelihood ratio test, believe me I have spent hours looking. Here is a question I've been trying to complete but I can't get any further. ...
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1answer
69 views

Too many p-value less than 0.0001 is alarming?

Can anyone explain why having too many p-value less than 0.001 is alarming? Like what happens to my model right now: All independent variables are categorical except for Calendar_Year. There are ...
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41 views

Test hypothesis point process is Poisson

I have some data and I would like to test the hypothesis that they come from a homogeneous Poisson process. I can of course look at the inter event times and test if these are exponentially ...
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22 views

Chi-squared test with scipy: what's the difference between chi2_contingency and chisquare?

I'd like to run a chi-squared test in Python with scipy. I've created code to do this, but I don't know if what I'm doing is right, because the scipy docs are quite sparse. Background first: I have ...
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Cooccurence of Two Categorical Variables

I am trying to calculate if there is a dependence between two categorical columns, or a significant cooccurence of two categorical variables. Let's say I have columns A and B, and and out of 200K ...
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22 views

How do we perform a two-tailed z-test when we *do* know the population mean of the intervention sample?

I am in the process of working through the Udacity course Intro to Inferential Statistics. In Lesson 9: Hypothesis Testing, the following example is given. Say that we record survey data from all ...
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39 views

Constrained Maximization and Likelihood Ratio Tests for Nested Linear Models

Suppose $\boldsymbol \beta \in \mathbb{R}^k$ is a vector of coefficients for a generalized linear model with $g \left[ E(Y|X) \right] = X\beta$ for a link function $g$ and I wish to test the composite ...
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34 views

Find significance level of hypothesis

I'm given two random sample datasets of sample size n=20, where the first dataset represents the weights of random boys, and second group represents weights of random girls. I need to find the ...
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37 views

Is the population of blue-eyed Martians decreasing?

Suppose that we want to test the hypothesis that the proportion of blue-eyed martians has been decreasing throughout the 20th century. Unfortunately, the Martian population fluctuates highly, so every ...
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22 views

Is the population of blue-eyed Martians decreasing? What about their number of brown tentacles? [closed]

Suppose that we want to test the hypothesis that the proportion of blue-eyed martians has been decreasing throughout the 20th century. Unfortunately, the Martian population fluctuates highly, so every ...
2
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1answer
19 views

Multiple-sample z-test for proportions

Let's say I want to do a multiple-sample z-test for proportions. Is there any way to rank them? How would I compare more than two samples at once?
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50 views

Does $\Pr(\text{Type I error})$ ever not equal $\alpha$ with continuous data?

This question: Comparing and contrasting, p-values, significance levels and type I error cites exceptions that arise when using discrete data. Are there other exceptions with continuous data as well?
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Testing association between exposure and disease

In a particular example from the book Epidemiologic Research by Kleinbaum [example 15.1], I have three problems. Consider the data in table 01. These data pertain to a follow-up study concerning the ...
2
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1answer
36 views

Approximating sample distribution standard deviation

I've seen in video lessons that if the sample size is big enough (n>30) sample distribution standard deviation can be approximated by sample standard deviation. How do we get the sample distribution ...
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70 views

Is it possible to accept the alternative hypothesis?

I'm aware of several related questions here (e.g., Hypothesis testing terminology surrounding null, Is it possible to prove a null hypothesis?) but I don't know the definitive answer for my question ...
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1answer
47 views

Is this method of finding the confidence interval correct?

Suppose that we have 2 sets of data $X = x_1, \dots, x_n$ and $Y = y_1, \dots, y_m$ and a test $T$ that tests the null hypothesis that these data come from a distribution with the same median. $T$ can ...
3
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1answer
50 views

What exactly does a Type III test do?

I'm having trouble understanding what exactly Type III test statistic does. Here is what I got from my book: "Type III" tests test for the significance of each explanatory variable, under the ...
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2answers
102 views

Two-Sample t-Test for Equal Means with unequal variances for large samples

How can I perform a two sample test of means with unequal variances for a very large sample in R? In case of large samples the statistic will asymptotically follow a normal distribution. Which R ...
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22 views

Out-of-sample vs. test set

Someone asked me if I did out-of-time testing (which I assume is just out-of-sample testing but with a timeline element). But if I have a test set, is that not essentially the same as out-of-sample ...
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What does “(scores mapped into 1:m using rounded scores)” from the 1-sample permutation test mean?

I'm trying to do an exact paired permutation test. What does this "mapping" mean? ...