Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [hypothesis-testing]

Hypothesis testing assesses whether data are inconsistent with a given hypothesis rather than being an effect of random fluctuations.

0
votes
0answers
18 views

Prove Zero Mean Hypothesis

I have a stochastic process for which I can compute a final outcome that is real valued. I know that the process has a relatively high variance and is costly to obtain more data points. (which I know ...
0
votes
0answers
34 views

Rating Scale Data: MoE vs Chi-Square vs WMW Rank Sum Test

I am working with Likelihood to Recommend metric that's measured on a scale of 1-10. The objective is to test for statistically significant improvement/decline (period over period) in the metric. On a ...
1
vote
0answers
21 views

Comparing Test and Control Lift in Proportion

I have two groups - a test/treated and control group - for which I am trying to assess whether the lift or percent change in proportion from a pre to post period between the two groups are unequal. I'...
2
votes
1answer
63 views

UMAU confidence interval for $\theta$ in a shifted exponential distribution

Suppose $X_1,X_2,\ldots,X_n$ is a random sample drawn from the distribution $$f_{\theta}(x)=e^{-(x-\theta)}\mathbf1_{x>\theta}$$ It can be shown that there exist some $c_{\alpha}, d_{\alpha}$ ...
0
votes
0answers
16 views

Relationship between chisquare test for trend and linear regression

In his book "Medical Statsitics, Fourth Edition", Martin bland explains that the chisquare test for trend can be used to evaluate a trend in a contingency table. He uses the following example: ...
14
votes
5answers
1k views

How do I compute whether my linear regression has a statistically significant difference from a known theoretical line?

I have some data which is fit along a roughly linear line: When I do a linear regression of these values, I get a linear equation: $$y = 0.997x-0.0136$$ In an ideal world, the equation should be $y ...
0
votes
1answer
30 views

A question about ANOVA

Question: My problem: Regarding the above question, a solution set was provided(although it was not explained by anyone). There the problem was solved by "One way ANOVA" model, Yij=u+eij, where ...
0
votes
0answers
36 views

Hypothesis testing for a known parameter value vs. for an estimated parameter value

I will motivate this question with 2 examples: Cointegration coefficient known vs. unknown The expectations theory of the term structure of interest rates establishes that the cointegration ...
0
votes
1answer
31 views

How to use bootstrapping to compare two non-normal datasets

I have two data sets - one control and one treatment. I wish to test whether the difference between their means is significant or not (approx 30 data values in each set). The distributions of both of ...
1
vote
1answer
30 views

Where is my potential flaw in my Z-test of Proportions?

I was working through this z-test of proportions example I found online. The online example solutions says that the difference between the groups is statistically significant, whereas I concluded it ...
1
vote
1answer
12 views

If through a procedure I am able to decrease the type 1 error in a statistical test, what implications does it have for statistical power?

In a testing procedure, say I am able to reduce my type 1 error, and that is the only thing it reduces. Am I able to make any conclusions about my statistical power, which is defined as 1 minus the ...
0
votes
0answers
14 views

How to compare two sets of time dependent proportions?

I am doing a sentiment analysis task about the people's attitudes towards transportation services in Hong Kong. I collected Tweets near the railway stations and see if there is any difference between ...
0
votes
0answers
7 views

Statistical test to validate score of perceptual speech quality

We would like to evaluate an algorithmic score of the perceived quality of speech after compression. The experiment will be to get a set of speech samples with different compression setings or ...
1
vote
0answers
26 views

How to Use Exploratory Data Analysis To Criticize Pre-Existing Hypotheses

Obviously, exploratory data analysis is a useful tool that can be used to support the hypothesis generation process in the social sciences. Especially in the age of big data. But, my coursework never ...
0
votes
1answer
38 views

What test for a 4-level categorical variable and a continuous variable?

I'm currently doing research on whether image quality affects engagement. Image quality is given in 4 categories (bad, benchmark, semi-professional and commercial level) and engagement is in how many ...
0
votes
0answers
25 views

how to use Likert Scale to prove hypothesis

How to use data collected from likert scale (five point) to prove hypothesis. For example. Hypothesis 1: Internet marketing is cost efficient. Statement 1: internet marketing required less budget. ...
0
votes
1answer
51 views

Transposing data: from repeated measures to independent samples

Assume that I conducted an experiment with 20 questions. The questions 1-10 are Type A questions whereas questions 11-20 are Type B questions. I am wondering whether two types of questions differ ...
0
votes
0answers
31 views

Multiple comparisons correction in between-subject classification analysis

I am working with a dataset of 46 subjects (23 controls and 23 patients) fmri brain t-maps each with 4 experimental conditions. The main purpose of my analysis is to find the highest classification ...
1
vote
0answers
26 views

Goodness-of-fit test when the sample space is monotonically increasing [closed]

I came across this paper which develops a GoF test on data drawn from a circular sample space (i.e. it has cyclical support). I am now wondering if there is a parallel to monotonic supports (or if ...
0
votes
0answers
12 views

Goodness-of-fit test applied to tuples in sequences/samples, instead of raw data

High level problem: I have two sequences of data. The first one is the reference, the truth, the second is one which contains missed values (due to measurement errors). I want a test which can ...
4
votes
1answer
89 views

How to perform over-dispersion test where null is quasi-Poisson

If I understand correctly, a quasi Poisson regression assumes roughly that $$ \mbox{E}\left[y\left|x\right.\right] = \exp{\left(x^{\top}\beta\right)}, \quad \mbox{VAR}\left(y\left|x\right.\right) = \...
0
votes
0answers
48 views

Bayesian hypothesis test: Type I and II errors

In a Bayesian hypothesis test between two alternatives A and B, what is the probability of making a type I and type II error? This question has been asked many times on this forum in various formats: ...
1
vote
0answers
34 views

Replicating a wrong analysis

A study measures the performance of patients and controls in two tasks. In task 1, a t-test reveals no significant differences between patients and controls. In task 2, a t-test reveals significant ...
0
votes
0answers
15 views

which test to use

I'm wondering which statistics should I use. I’ve conducted an acceptability judgment task using 7 point scale for 8 different conditions. My study has a 2*2*2 factorial design with two level for each ...
1
vote
2answers
49 views

How is the standard deviation in this coin tossing experiment calculated?

I'm reading Hypothesis Testing: The Basics, there is such an experiment: So, we have a coin. Our null hypothesis is that this coin is fair. We flip it 100 times and it comes up heads 51 times. Do ...
1
vote
1answer
41 views

Which statistical test to use? Not really paired, not entirely unpaired

I am setting up an experiment where I would like to determine whether there exists a difference between the participants' average self reported mental effort in some condition A and condition B. The ...
2
votes
0answers
35 views

Is this a proper use of the Karlin-Rubin UMP test theorem?

For iid $X_1,...,X_n$ and the unknown parameter $\theta>1$, suppose that the likelihood function of a particular sample is given by: $$L(x;\theta)=log(\theta)^n\theta^{{n-\sum_{{i=1}}^nx_i}} I(x_{(...
1
vote
2answers
70 views

How to determine sample size for Chi-squared test?

Similar questions have been asked here on CV, however I have not found a solution to my specific question yet. I am trying to plan a sample size for chi-squared test. However, I struggle to find the ...
3
votes
1answer
50 views

Transitivity of statistical significance

Say I have three sets of observations, $A$, $B$, and $C$ (say, the heights of Australians, Americans and Brits). I assume that they are all normally distributed, independent etc. I perform two-sided ...
0
votes
0answers
39 views

How to calculate studentized bootstrap pvalue for H0 assuming % difference between population means?

First of all I'd like to mention, that I've read at least 2 great discussions on the site, which helped me a lot. Very thorough explanations of H0 data generation are presented here and here. But ...
1
vote
0answers
31 views

Understanding equivalence testing. Why there are two hypothesis?

I have to two groups and I would like to test that difference between means of these two groups is at least 0.02. I am using TOSTER R package. Here are details: ...
0
votes
0answers
11 views

Sound unit testing of convergence of an implementation of a stochastic algorithm

(My statistics knowledge comes mainly from computer science, so I might be overthinking the following...) I have implementations of several stochastic optimization algorithms (evolutionary algorithms,...
0
votes
0answers
15 views

Break down a 2-by-3 within within ANOVA into two 2-by-2 within within ANOVA

I have data that may be arrayed as a 2 (Time: A1 vs. A2) by 3 (Difficulty: B1, B2, B3) within-within factorial. But I'm not interested in the comparison of difficulty B2 and B3 over Time. Is it ...
2
votes
1answer
84 views

Wilcoxon signed-rank test or One Sample t-test?

I conducted a training session and for each of my users, I measured pre and post score (before and after training session). Each of my users (n=28) is measured twice, so my data is paired: Data: <...
0
votes
0answers
16 views

What statistical to use - variability between but not within

I have a data set where each line represents a participant's response to a series of questions (e.g., attitudes towards democracy, life satisfaction). Participants were recruited from different ...
0
votes
0answers
23 views

Confidence interval of one tailed Z-test

In an intelligence test of boys and girls, the question has asked to find if the boys and girls are equally intelligent against the alternative that girls are more intelligent than boys. While I have ...
2
votes
1answer
38 views

Why replication studies use two-tailed tests?

I have been searching replication studies and I found that all of them use two-tailed tests. For example: Open Science Collaboration. (2015). Estimating the reproducibility of psychological science....
1
vote
1answer
37 views

Logical Hypothesis Modification

I performed an experiment with a treatment and a control group. It just so happened that my treatment could be modified to either increase or decrease my dependent variable. So, I decided to test two ...
10
votes
5answers
1k views

Why do we need alternative hypothesis?

When we do testing we end up with two outcomes. 1) We reject null hypothesis 2) We fail to reject null hypothesis. We do not talk about accepting alternative hypotheses. If we do not talk about ...
0
votes
0answers
26 views

One-sided variance test in r [duplicate]

I would like to compare variances of two independent samples (of different sizes) from two unknown distributions. It seems I should use a one-sided nonparametric test. Bartlett's and Fligner's tests ...
0
votes
0answers
24 views

test of relation when one variable is itself a mean?

What is an appropriate test to see if there is a relationship between two things, where one of them is itself obtained by averaging human rankings. As an example, there are good and bad bottles of ...
0
votes
1answer
91 views

Setting up contrasts in lmer?

0 I have 139 subjects (ID), with measurements taken at two time points (Time1, Time2), at 148 brain regions, a dependent measure called volume, and a covariate called thickness. Each subject has 148 ...
1
vote
0answers
25 views

Solution verification for a hypothesis testing question

I am posting this question as a solution checking. Let $X_1,...,X_{30}$ be a random sample from the exponential distribution with unknown mean $\mu\in \{1,1/\delta\}$ (where $\delta>1)$. Consider ...
0
votes
1answer
23 views

Comparing main effects and interactions on the same significance scale

When we collect genomics/metabolomics/proteomics data (many variables) in a between-by-within 2-way experimental design, we are often interested in which variables change differently between groups (...
0
votes
0answers
19 views

Information gain or regression for measuring to what extent a continuous quantity detemines a discrete one?

I have a small population S and two quantities P and Q associated to its members. P is integer valued (say, age taking integer values between 1 and 20) and Q real valued (say, height in meters). I can ...
1
vote
1answer
30 views

Are there statistical tests for testing multiple sample proportion?

For categorical variable testing, we have chi-square test. For example, we want to test if a dice is fair (assuming sample has [6,5,7,7,6,5] and ...
1
vote
0answers
28 views

What test should one use when dealing with different treatments in plant clones?

In an experiment involving plant clones there are: 20+ treatments, 5 technical replicates for each treatment (plant clones in which the treatments were tested). Variable of interest is Biomass. Due ...
0
votes
1answer
24 views

Should I adjust for family-wise error when doing many logistic regressions and t tests

In my biomarker analysis, there are 100 biomarkers. Each biomarker is measured at 4 different time points. I'm looking for any biomarker that is associated with outcome variable at any timepoints. ...
0
votes
2answers
30 views

Paired t-test with inequality in $H_0$

I have read that paired $t$-test works assuming a null hypothesis with equality, i.e: $$H_0 : \mu = \mu_0 $$ Is there any way to do the same test with an inequality, such as: $$H_0 : \mu \geq \mu_0 $$ ...
0
votes
1answer
31 views

How to measure risk of a Type 2 error in A/B tests

I'm conducting A/B tests where outcomes are binary (success or failure in control and experiment populations). The assessment of the risk of a Type 1 error is relatively straightforward: given an ...