Questions tagged [binomial-distribution]
The binomial distribution gives the frequencies of "successes" in a fixed number of independent "trials". Use this tag for questions about data that might be binomially distributed or for questions about the theory of this distribution.
2,461 questions
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How to justify that testing 20 sprinklers (out of ≤5000) is a statistically meaningful sample?
In fire-protection maintenance, we often need to test a sample of sprinklers that have been in service for about 25 years.
Each test is pass/fail, and the parameter of interest is the failure ...
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Fitting of data when datapoints come from binomial distribution
I have the following question. I have some data $p(x)$ where each datapoint comes from averaging 100 independent binary experiments. Although it is irrelevant for the question, I am measuring quantum ...
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Residual issues in binomial GLMM when including random effect
I'm working on a dataset of ~2900 fish, where the visually estimated sex was compared to the true sex. In about 10% of the cases (≈260 fish), the estimation was wrong (deviation = TRUE).
I'd like to ...
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Two ideas to include measurment errors in a Binomial Test with different results
I have a measurement with two possible outcomes, let's say 0 and 1. If the outcome of the measurement is 1, the true value is always 1. If the outcome of the measurement is 0, there is a chance of 1% ...
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Estimating and interpreting causal effect of a continuous exposure variable on binary outcome using double machine learning
I'm using double machine learning in the structural causal modeling (SCM) framework to evaluate the effect of diet on dispersal in birds. I'm adjusting for confounding variables using the backdoor ...
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Sample size calculation for a test on proportions
I'm not sure whether I'm assessing this problem correctly.
Suppose I want do demonstrate that an adverse event occurs in less than 20% of the participants (but I hope/assume that it actually NEVER ...
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glmmTMB warns of false convergence with betabinomial models but no with bin or negbin models
I've been looking for the best distribution to fit a glmm model to my data. The best seems to be a betabinomial model, but it gives a warning about false convergence, which is caused by large z values:...
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Why does glmer give a "nearly unidentifiable, rescale variables" message and glmmTMB does not, when fitting a binomial model?
I was fitting the following binary glmm with glmer:
...
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Predicting global outcomes with logistic model
I have a database of many employees, and i want to estimate how many are going to retire next year, based on many retired last year. So i thought about a logistic model like
glm(retire ~ age2025 + ...
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Why are the point estimates of estimated marginal means from a Bayesian binomial GLMM so different in the presence of residual covariance?
As the question title says, I am confused why the estimated marginal means (obtained using emmeans()) for a Bayesian binomial generalized linear mixed model are so ...
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Understanding outputs, should we calibrate probabilities obtained in logistic regression models such as GAM INLA?
I am developing a species distribution model for a rare, data-scarce species. To explore the effect of sample prevalence, I fitted several models with different presence–absence ratios by randomly ...
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How to determine the variance and distribution type of data when fitting GLM in R
To select the correct type of data distribution (Poisson, quasi-Poisson, double Poisson regression, generalized Poisson regression, gamma, binomial distribution, negative binomial distribution, etc.), ...
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Bounding the Tail of a Sum of Dependent Bernoulli Variables via Conditional Expectations
I'm working on a problem that arises in a physics context and involves probabilistic modeling using binary outcomes. I'm not a mathematician by training, so apologies in advance if I miss standard ...
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Tail bounds for bivariate binomial distribution
I'm interested in estimating the joint upper tail probability of two correlated binomial random variables, say:
$$
X \sim \mathrm{Bin}(n, p_1), \quad Y \sim \mathrm{Bin}(n, p_2),
$$
such that $corr_{...
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emmeans output for binomial GLMM : why values are all higher than observations?
I want to test whether the probability of a shoot to flower depends on two factors (Modality and Group). To do this, I've used a GLMM with a binomial distribution and added a random term to account ...
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Different ratios (3755 vs 1.04) for overdispersion ratio using different methods - check_overdispersion vs manually - why?
I have a model and when testing for overdispersion I used manual method and also check_overdispersion from the Performance package, and got massively different ratios (although both were overdispersed....
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Please help me understand an example in a section 'Sampling Methods and Distributions'
It is one example in rudimentary statistics class.
A professor writes a statistics test and estimates that 90% of
test takers will complete the test in 1 hour or less. She gives the
test to a class ...
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Why does centering and scaling change my model (binomial response glmm) coefficients' p-values, but just scaling doesn't? [duplicate]
I have a glmm in R with 4 fixed effects, 4 interaction effects, 2 random effects, and a binomial response variable. I have two versions of this model, both with the same model strucure:
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Confidence Interval for Population with Disproportionate Stratified Random Sample
I am reviewing data from a stratified random sample to describe the proportion of the total population exhibiting Trait A ($p_A$). Due to time/resource constraints, I conducted a disproportionate SRS ...
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Plotting min and max bit-error rate at at a given confidence level using Binomial CDF. Why are my values are swapped? [closed]
I am writing a Python function to calculate the minimum or maximum bit-error rate (BER) in a system for a given number of transmitted bits, number of errors, and desired confidence level. I ...
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Beta-binomial vs binomial GLMM for modeling longitudinal 0–30 day substance use outcomes: DHARMa, dispersion, zero-inflation, prediction issues
Context : I’m working with a longitudinal cohort of patients followed for substance use disorders (n ≈ 3300 observations, 900 subjects). The outcome is the number of days of substance use over the ...
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Unbalanced number of observations in the levels of predictors in binomial GLM
I'm running a binomial GLM to test for the effect of context (3 levels) and identity (4 levels) on the occurrence (absence/presence) of a phenomenon (specific type of vocalization). The context -> ...
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What statistical test should be used? (binomially distributed variable, low probability, insufficient number of tries)
I am sorry for such a vague title, but I'll try to give a good example for my problem.
Suppose, in their blood people have red and white blood cells and may (or may not) have a very small fraction (...
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Testing for Binomial distribution
I have two different processes where I want to test whether they are well approximated by a binomial distribution. My data consists of lots of triples of the form (N= number of trials, p=success ...
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Maximum likelihood for binomial variables
Let's say we have two binomial variables $Y_1$, $Y_2$ such that for $Y_1$ number of trials $n = 103$ and number of successes $k = 51$ and for $Y_2$ number of trials $n = 53$ and number of successes $k ...
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How is the threshold determined in the Monobit Test, and why is it larger for a 1% significance level than for 5%?
In the Monobit Test for randomness, the threshold for passing or failing is based on a confidence interval. I understand that a 1% significance level (99% confidence) results in a larger threshold ...
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Does p=1/2 always lead to the worst-case sample size for Clopper-Pearson interval?
I want to give an a priori bound on the number of samples needed to obtain a confidence interval where the (a) expected width, and (b) worst-case width is $\leq \varepsilon$ using the Clopper-Pearson ...
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Binomial MLE, unknown number of trials (Casella and Berger, Example 7.2.9)
Let $X_1, \ldots, X_n$ be a random sample from a $\text{Binomial}(k,p)$ population where $p$ is known and $k$ is unknown. The likelihood function is
$$ L(k|\mathbf{x}, p) = \prod_{i=1}^{n} \binom{k}{...
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Model selection for fixed effect and crossed random effect structure in glmer
I'm new to (generalized) linear mixed effects models. Any help would be appreciated!
Below is my study design with dummy data. I'm exploring the effects of the parameters I manipulated in game 1 on ...
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How to model a binary outcome with three possible exposure variables and multiple levels of nesting?
I have an odd animal study design which was based on one performed in the literature, but my modifications resulted in a very complex structure...
I'm using R with the ...
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How do I make an M-estimator out of a GLM if the variance depends on a dispersion?
This question is also posted on Mathematics Stack Exchange https://math.stackexchange.com/questions/5038432/how-do-i-make-an-m-estimator-out-of-a-glm-if-the-variance-depends-on-a-dispersio.
A ...
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differentiating the normalization term of a Binomial Distribution to get the variance [closed]
I am working through exercise 2.4 in Bishop's Pattern Recognition and Machine Learning. The problem asks to differentiate the normalization condition with respect to u to obtain an expression for the ...
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Confidence interval for the number of unique items seen after $j$ days
Suppose I have 100 fish in a pond.
Each day, I decide how many fish I want to catch - a random number between 1-10
Each fish has an equal probability of being caught on any day.
No new fish can enter ...
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Determine sample size for validating success probability of Bernoulli process
Given a process producing a product with some constant defect rate $d$, I want to estimate the minimum sample size $n$ to confirm with a probability greater than or equal to $\alpha$ that the defect ...
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What qualifies as "near-zero" random effect variance in GLMM?
I'm trying to better understand how to select random effects in a binomial GLMM. Currently, I'm using a forward-selection approach with AIC and likelihood ratio tests, but I'm also interested in ...
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What params to use on GLM from statsmodels
I am modeling how a a chemical reaction yield (Y) depends on the ratio between reagents (X). The higher the ratio, the higher the reagent conversion, with a clear inflection at around 1.5. Below is ...
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How to compute confidence intervals for changes in sales, returns, and return rates in independent auction experiments?
Question
Suppose I am organizing a car auction and conducting two independent experiments:
Auction A is conducted 1000 times.
Auction B is conducted 1000 times.
(For instance, I change the auctioneer ...
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What is the distribution of a windowed-sum binomial process?
Let's say I am flipping a fair coin.
If I do m independent trials of n flips, I expect the total flips of each trial to be ...
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Binomial confidence interval over the number of trials
I have a process which succeeds with known probability $p$, and fails with probability $q = 1-p$. The process is repeated a finite, but unknown, number of times $n$.
Given a number of successes $r$ (...
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The binomial distribution - can the IID assumption be relaxed?
I have done some reading and have re-written my question to make it a little more precise ( I hope ).
It is known from previous surveys that 50% residents oppose a policy. It is decided to contact ...
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Correct binomial GLMM for temporal trends in species occurrences
I have a dataset with 80 species which were sampled in about 120 water bodies at two time periods (historical / recent). Only presence/absence of the species in each water body is considered. The data ...
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What is the probability that some card will end up as the top 10 $k$ times after $n$ shuffles?
I'm trying to calculate the probability that after, $n$ shuffles, some card ends up within the top 10 places $k$ times. I think I have got the answer, but I think I might be missing something.
So with ...
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How to verify and report results from a glm with family = quasibinomial?
I estimated a glm with the family = quasibinomial. My dependent variable is continuous survival rate, which ranges from 0 to 1 with (like: 0, 0,1, 0,2.....,1). My ...
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Is a sequential binomial sample a multinomial sample?
Say I have N particles and I remove a fraction $f_1$ of these obtaining $k_1$ particles as
$$ k_1 \sim \text{Binomial}(N,f_1) $$
and from these selected $k_1$ I have another Binomial draw of $k_2$ ...
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Head First Statistics Book: error in hypothesis test?
Chapter 13 in the book Head First Statistics deals with hypothesis testing. Its example is like the below:
A drug (called snorecull) cures snore at a rate, 0.9. Then, one gets
the below results.
...
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Determining number of observations be within confidence threshold
I have a model which has an accuracy of $A$. It makes a prediction with $Y$ confidence about a number of samples. Samples are observed many times, but not all are observed equally. So my data looks ...
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What's the difference between Binomial model versus Poisson model with an offset for GLM
I am working with binned data indexed by $( i = 1, \ldots, n )$, where for each bin $i$, I have:
$( X_i )$: the number of successes
$( N_i )$: the total number of trials
I want to model the ...
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Can an Election be Modelled with a Binomial Distribution [closed]
In my province there was an election recently. In one area the conservative candidate led by 103 votes compared to the progressive candidate. Each received over 8500 votes. The other parties combined ...
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Binomial test for 1:1 ratio (Python) [duplicate]
I have collected data on gender ratios that looks like this:
These are counts. I evaluated 100 employees from each company, each department. And then evaluated whether they're Male or Female.
...
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Binomial test for finding ratios
I have tried reading about the concept here:
https://www.ncl.ac.uk/webtemplate/ask-assets/external/maths-resources/statistics/hypothesis-testing/hypothesis-testing-with-the-binomial-distribution.html
...