All Questions

I'm currently writing a project proposal in which i've been told i need to estimate the sample size i require. Im planning to look at the effect of culture time (split into three groups) on IVF ...

I have a dataset of precincts and results of parties on different elections (let's focus on two : 2008). After reading this article I really wanted to use linear regression to answer the question : ...

I have been using the crch package for modelling censored data with the tobit model. I noticed early on that the errors (by far) are not normally distributed by ...

Given the p-value is less than 0.05 does negative Z score in two-sided Cochran-Armitage test implies the presence of an increasing trend?

I ran Croston's Method on this data(Sales) with h=3 ...

I'm currently working on image classification, i want to divide the input image into sub-regions(patches) and apply a deep convolutional neural network (CNN) to train and classify each patch ...

I have the equation, Y = A*B*C/(D*E) Where A, B, C, D and E are the certain parameters of 1000 samples (say groundwater samples). ...

I'm using the forecast R package. I have the same dilemma as How to forecast daily time series with weekends and holidays?. I understand that the answers consensus ...

I stumpled upon the definition of a prediction interval from https://www.statisticshowto.datasciencecentral.com/prediction-interval/ In my setup I have a type of tree-based regression model with non-...

My textbook, Introduction to Probability, by Blitzstein and Hwang, provides the following problem: Let $X = V + W$ and $Y = V + Z$ where $V$, $W$, and $Z$ are independent $\text{Pois}(\lambda)$ ...

Consider the random effects ANOVA model below (notation based on Snijders and Bosker, 1999), where $j$ represents a group and $i$ an individual: $$ Y_{ij} = \mu + U_j + R_{ij}, \qquad var(Y_{ij}) = \...

I need to find clusters in a very large amount of data (>2M data points), and I was looking for ways to speed up the usual algorithms, i.e. k-Means, DBSCAN, ... Is there any major issue, especially ...

You are guessing the contents of two envelopes. Let Ui be the event that you guess correctly. Your probability of guessing correctly for each envelope is P(U1) = P(U2) = 3/4. U1 and U2 may or may not ...

I hope you would be able to help me! I am working on a LMM in SPSS right now and I've gotten to the point where I don't really know what to do. I am looking into comfort (so that is my DV, measured ...

I hope someone can help. Please let me know if my question is not clear. I have compositional data, where there are three variables which sum to 100% for each row, something like this: ...

I have text samples pre-split in training / test for binary sentiment classification. I have a suspicion that the test set was sampled from a different domain than the training set. There are several ...

To briefly summarize, I have a bootstrapped data set that needs to be corrected for multiple comparisons. The figure below provides a snapshot of one set of the data. The x-axis is in bins of 60ms. ...

I have columns 'Longitude', 'Lattitude' and 'Battery' in my dataframe. I want to define a function if the difference between alternate battery value is more than a threshold, it should return 2 ...

For a metropolis hastings algorithm, suppose that the stationary distribution is defined as the Gibbs Boltzmann distribution $\pi_T(x)= \frac{1}{Z_T}e^{-\frac{V(x)}{T} }$ where $Z_T = \sum_{y\in V} e^{...

I have a good amount of variables, where some/most of them are highly correlated. Like roughly 80 variables, and then maybe 50 are correlated in groups. So 20 of the 50 are highly correlated, and the ...

What is the support of some function $F$ and why do we care about it? Is it of major significance for distribution functions?

I'm following hydman's advice for using fourier terms when fitting a linear regression model to the taylor time-series (with the very long seasonality of 336). My ...

This is the question: There are particular readers for swipe cards, Under normal operating conditions, there is a small probability of 0.02 that swiping a card fails to open the entrance - some of ...

can i conduct/estimate/ an incidence rate in case control study and also is it possible to analysis survival from case control study?..as my knowledge incidence rate will be best ok with cohort study,,...

I have calculated hettest using STATA and i have found two models have no Heteroscedasticity problem. but i can not identify which one is the best model for my data. can you please help me out? I ...

I'm working on Introduction to Probability Theory by Joseph Blitzstein. Definition 3.2.1(Discrete random variable). A random variable $X$ is said to be discrete if there is a finite list of values $...

Working with the Golub dataset, I am attempting to use the Wilcoxon two-sample test to find the genes that have a higher mean expression value in the AML group as compared to the ALL group. What is ...

I am trying to forecast the battery charge for the next 2 days. I have data for 3 days with 5 mins interval. I have tried the below code: import statsmodels.api as sm arima_mod = sm.tsa.ARIMA(...

as picture shows it says A, B are independent which means P(A,B) = P(A)P(B). then isn't pmi always 0? because log1 = 0? what am i assuming wrong here?

What are the odds Ive met my other half? Thing is I already know I have with this undeniable experience we had when our souls actually collided together as we were one. I just want to know what ...

I'm struggling to find a model that will best fit this data. The dependent variable is the ranking of a observation based on how many votes it received based of a list of choices (number of votes is ...

I have a correlation matrix of 40 random variables: $C_{ij}$, $1 \leq i,j \leq 40$ I want to partition the 40 variables into two groups (of 20 each) such that the average correlation differs by most ...

So I have this dataset where I have species community data from a variety of sites. I’m trying to explain what are the factors that drive the variation in these data. For each site, I have a ...

Using the "Example Dataset," complete the following: Based on a normal distribution curve, calculate the probability of an individual being 60 years or older in this population. SPSS formulas ...

Suppose one has an n × 2 matrix X (the independent variables) and a n × 1 vector y (the dependent variable). In a standard multiple linear regression setting, we solve for the 2 × 1 beta vector that ...

can i use logistic regression in discrete feature types problem. Since recently i knew that the expression for logistic regression is derived from guassian naive bayes and we can use guassian naive ...

I am working with MLB data with around 15000 observations for seasonal player stat. The data frame's structure looks like this (I'm making up the stats): ...

I have sets of data that have number of goods produced by 2 machines, A & B for 2 months. Each machines has two numbers that is plan value and actual value. I'm not really familiar with hypothesis ...

In mathematics, the multinomial theorem describes how to expand a power of a sum in terms of powers of the terms in that sum. It is the generalization of the binomial theorem from binomials to ...

A large data containing the amount of SO2 concentration from the exhaust of cars in the USA is available. Let's say I am a car company agent and the USA government asked me to come up with a "maximum ...

The organizers of a banquet at a restaurant have ordered 10 place settings, but they have invited 13 people. Past experience indicates that 15% of the people who are invited independently decide not ...

I have two random variables $X$ and $Y$ with given (mean, variance) as $(\mu_{X}, \sigma_{X})$ and $(\mu_{Y}, \sigma_{Y})$, respectively. These random variables have their truncated counterparts: $tr(...

Say I have a multivariate normal vector $r$~$N(\mu , \Sigma )$ and I observe that $ y \equiv Pr + \epsilon = Q$ where $P$ is a matrix and $Q$ a vector and $\epsilon$~$N(0 , \Omega )$. Now I ...

How do I convert the $\text{MAD}$ (median absolute deviation from the median) of data that is drawn from a log-normal distribution to the standard deviation of a log-normal distribution? To clarify, ...

Can someone explain how confidence intervals for ARIMA forecasts are derived? I can't seem to find any good explanation of it. From what I've read it seems like because an ARIMA process can be ...

Multinomial logistic regression have assume the IIA (independence of irrelevant alternatives (IIA), IIA assumption: difference logit and probit); but I'm wondering if using Neural network in which the ...

I have a dataframe (DF) that consists of 2 variables with ~43500 observations. The first variable is a numeric (1-6), the other is a factor with 2 levels (PRE & POST). Why does R give a different ...

I'm a newbie to statistics, so I apologize if this question is trivial. I'm trying to build a distribution that can predict a specific set of images. But first, I need a baseline - so, I decided to ...

I'm trying to translate this thing into a working algorithm. The paper here describes the algorithm implemented in MatLab. There is an alleged python translation here. but I never managed, or saw ...

I am comparing the blitz frequency for a football team by down (1,2,3) How can I determine if the frequency for blitzing on first down is significant compared second and third down...etc. I have the ...