All Questions

0
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0answers
2 views

estimate equal distribution of few points on a line

I am trying to find the best solution to estimate equal distribution of points over a line. I know I can use relative SD or similar, but I was wondering if there are more "specific" methods that can ...
0
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0answers
3 views

Confidence intervals for state space models

i'm looking for on how to calculate the following ICs: smoothing, on-line filter and prediction on state space models. I'm not able to find any formula about them or any matlab command/class. Thanks....
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0answers
3 views

Re-scaling of exponentially distributed random numbers

I am trying to generate $M$ random numbers which are exponentially distributed and whose sum adds up to $N$ (for simplicity, $N=1$). I found that the generated numbers are initially exponentially ...
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0answers
4 views

How to deal with repeated words in training and testing set using CART?

I have a dataset where a child read a passage out loud. Each row is one word (I’m order of the passage). I have a 1/0 for whether they read the word incorrectly or correctly. I’m trying to predict ...
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0answers
8 views

Likelihood ratio statistic lognormal

I want to determine the LRS lambda of a lognormal distribution under H0: the variances are equal. What I have so far is the following: $H0: \sigma^2 = \sigma_{o}^{2}$ $H1: \sigma^2 =! \sigma_{o}^{2}...
1
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0answers
6 views

Test to compare means of non independent samples with repeated measures

I am struggling a little to know if I am comparing independent or not independent data and I am not sure what kind of test I should use. Here is the pitch : I would like to compare latencies between ...
1
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0answers
9 views

How to calculate the mean over uneven observation times?

Possibly a very basic question, but I would really appreciate clarification from those with a strong background in stats/epi. I have a number of human patient medical records. They are retrospective ...
0
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0answers
8 views

Extreme Value Simulation from Copulas with Monte Carlo

I'm trying to simulate the tail values from a multivariate distribution using copulas. I'm using Vine Copula package of R to derive the suitable copula for my data and I generate random samples out of ...
0
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0answers
5 views

Mediation, All significant but negative total effect, positive direct effect, negative indirect effect - Help!

I am doing a mediation analysis using PROCESS, and need some help with the below: Total effect of X on Y ...
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0answers
3 views

Statistical analysis of multiple trials (3 categories) at 3 time periods for 2 group of subjects

I am confused about statistical analysis of an experiment in which there are two groups of subjects i.e. experimental & control. Each group goes through a treatment and multiple readings of ...
0
votes
1answer
10 views

Question related to poisson process [on hold]

Customers arrive at a bank at a Poisson rate of λ. Let M(t) be the number of customers who enter the bank by time t only to make deposits to their accounts. Suppose that, independent of other ...
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0answers
4 views

Beta Coefficient for Gaussian Process with Non-Zero Mean

I'm reading through Rasmussen & Williams (2006)'s book on Gaussian Processes, specifically on section 2.7 on incorporating explicit basis function. I am confused on how the analytical solution $\...
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0answers
10 views

Comparer deux groupes [on hold]

J'ai deux groupe classe, un qui a reçu un cours de mathématique en utilisant la tablette et un autre ayant reçu un enseignement traditionnel. Je dois voir si la tablette a aidé les élèves à obtenir ...
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0answers
14 views

Estimation of NegEntropy in MATLAB

I am trying to evaluate the different ICA algorithms using MATLAB. To do that, one of the measure which I use is to estimate the non-gaussianity using NegEntropy. I am trying to find a function which ...
0
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0answers
3 views

Measuring effects of IV (constant) on DV

I have an independent variable (a bias) that is technically a constant. I want to measure the effects of the IV on the DV. How do I do this? I'm using SPSS. Let's say, participants produced A or B ...
0
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0answers
10 views

StepAIC with tslm function in R

I wish to forecast a timeseries and so I use something like this : Suppose I have a data xtrain with V1,V2,V3,V4 as the attribues. Then, I will create a model as follows : form=as.formula(train ~ ...
-1
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0answers
8 views

Most influencer city

My Problem goes like this: Suppose the cities of world, each city has a degree of economic collaboration with other cities. I need to detect communities such that the degrees among different cities ...
1
vote
2answers
18 views

R-Squared for a non linear curve

At the start, please forgive me if my question is too elementary. I am fitting a non-linear curve. Say a parabola. The data points I have are close to a parabola and the best output I get is a ...
0
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0answers
6 views

Local Significance test for composite anomalies

Suppose I have the following 20 points: ...
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0answers
8 views

Moderation analysis with non-significant main effects but significant interaction

I am doing a simple moderation analysis with one independent variable (IV), one moderator (M) and one dependent variable (DV). Results indicate that a regression model containing both main effects (...
0
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0answers
7 views

Which statistical tool would be useful to check whether a variable has changed significantly over years

I have precipitation data of around 40 years of 10 stations but some missing data in the middle. I want to check whether the precipitation has changed significantly over the decades in the region so ...
4
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0answers
22 views

How to show a UMVUE exists only if $g(p)$ is a polynomial of degree at most $n$?

Let $X\sim Bin(n,p)$. The problem is to show that a UMVUE can exist for $g(p)$ only if $g(p)$ is a polynomial in $p$ of degree at most $n$. For the case when $g(p) = \frac{1}{p}$ we can show that it ...
0
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0answers
7 views

BayesFactor anovaBF syntax

I want to get Bayes factors for ANOVAs that are analogous to the classical F-tests, and I just want to make sure I understand correctly how to write the syntax, especially regarding subject IDs. For ...
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0answers
3 views

hoc test and pearson corelation

Please can you help me how to report post hoc multiple comparison? is it write to report them in that way (M=...., SD=......), i wrote them in that way. And another question how can I report a ...
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0answers
10 views

How to transform Beta distribution of second kind into Beta distribution of first kind?

! I tried to solve it in a way but I can't complete in as I don't get any idea how to integrate the Beta kind two integrand within a finite boundary.
0
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0answers
9 views

Use of adjusted R^2 when regressing using overlapping data

Context: Taking time series levels and converting to 10 day changes in levels. Then doing a linear regression on the 10 day changes over a period of time eg 500 overlapping samples, where Y is the ...
0
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0answers
6 views

measurements with gaussian error

I'm reading a printed document(learning material) which says "Person A made measurements of a quantity, with Gaussian errors". To me this expression seems odd and the meaning is unclear. Is that a ...
0
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0answers
11 views

confidence interval for the variance with unknown distribution

Let $X_i \sim \text{iid}(\mu, \sigma^2)$ (the question does not specify whether or not $\mu$ and $\sigma^2$ are known). I have to show the confidence interval for the variance. Since $X_i$ is not ...
1
vote
1answer
16 views

Making the mindset transition - projection in OLS regression

For example, the space spanned by the columns in $$\mathbf{X} = \begin{bmatrix} 0 & 0 \\ 1 & 0 \\ 0 & 1 \end{bmatrix}$$ is the y-z plane. Further, $$\mathbf{X'X} = \begin{bmatrix} 1 &...
0
votes
0answers
7 views

Select coefficients of significance for user ratings

I create an application with some social interaction between users. Users will have ratings that determines your recommendations - users are recommended to users with the same rating.Total rating of ...
0
votes
0answers
8 views

ROC curve with symmetrical kernel

I am trying to use kernels with ROC curve, and 'm succeed to plot them but now my query is about theoretical grounds, i.e. its bias, var, etc. I want to evaluate the theorems (1 & 2) in Pulit (...
0
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0answers
7 views

Measures of discrepancy between the kernel density estimator f^ and the true density f

My understanding is that, density estimation is the construction of an estimate, based on observed data, of an unobservable underlying probability density function. So my question is, how does L2 ...
0
votes
0answers
3 views

Should a factor analysis (for construct validity) be performed in a section of a test that is meant to measure knowledge in a specific subject?

As a part of a study, a survey to measure the impact of an environmental education project is being developed, and to do so, factor analysis and principal component analysis are being performed for ...
2
votes
1answer
15 views

Weighted Categorical Variable

Consider for example I have a retrospective data that contains one categorical variable Race and one other variable Weight <...
0
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0answers
23 views

Statistics: what kind of test to use to test this hypothesis?

I am unsure what kind of a hypothesis test to use in my case: So we are filling 500 ml bottles with water; It's a known fact that before a max of 3% of all the bottles could be under-filled; Now I ...
0
votes
0answers
12 views

Relation between prior odds and the prior distribution of each parameter

When comparing models using Bayes factors in Bayesian statistics, one typically present the prior probability of each competing model in odds form. How do those prior odds compare to the prior ...
0
votes
0answers
7 views

Why is K-means prone to unequal size or density of clusters?

I have read in many articles like https://codeahoy.com/2017/02/19/cluster-analysis-using-k-means-explained/ and https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0162259#pone-...
0
votes
0answers
18 views

why Isn’t my neural network model working well for deep architecture compared to shallaow? [duplicate]

I’ve recently started learning about neural networks and currently am working on a NN to classify images of a cat vs non cat. I’ve built an option of customizing the number hidden layers and nodes per ...
0
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0answers
9 views

Conditional Covariance Problem

Suppose we have independent (not necessarily identical) normally distributed random variables X, Y. If we're given that, upon sampling each variable, X is some multiple a of Y (i.e. x = ay), what is ...
-1
votes
0answers
10 views

LASSO regression of continious data in R

I am not familiar with LASSO regression in R and generally with the field of statistics. I want to perform LASSO regression with continious variables. I tried everything that exists in google and in ...
0
votes
0answers
16 views

t-test comparing two slopes, specifically when slope values are small

I am performing a t-test to compare two slopes, each fit to independent X,Y data. Does the nature of this test change depending on the range of slopes being compared? For example, is comparing a ...
0
votes
0answers
8 views

Which emmeans to choose between full and main effect mixed effect models with heteroscedasticity corrected

I have a split splot full factorial design : 3 blocks, each block contains 4 plots for factor E and each plot is divided into 3 subplots for factor F. I use a mixed effect model with random effects on ...
2
votes
1answer
58 views

Inclusion of standard error in regression equation

$$ \begin{alignat}{14} P = 11&.32 &+ 0&.71 \,\text{PASN} &+ 1&.54 \,\text{DIS} &- 1&.02 \,\text{DIS}^2 &+ 3&.44 \,\text{FUEL} &+ 1&.36 \,\text{FIRST} &...
2
votes
1answer
26 views

Why is random sampling a non-differentiable operation?

This answer states that we cannot back-propagate through a random node. So, in the case of VAEs, you have the reparametrisation trick, which shifts the source of randomness to another variable ...
1
vote
3answers
26 views

Commonly used example data sets

Is there a place where one can get standard example data for various statistics tools to try on? For example, if one is learning about ARIMA models, where would one get data that can be modelled well ...
2
votes
0answers
12 views

Probability of sparse spectrum

Consider a vector $v$ such that $v \sim \mathrm{Unif}(\mathbb{S}^{d-1})$, the uniform distribution on the unit sphere in $d$ dimensions. Question: is there an upper bound on the probability that $v$ ...
1
vote
1answer
14 views

Is this a crossover design?

I am working with collaborators who are conducting an education research study to see if there is a difference in learning outcomes between two learning experiences, one with a technology tool (let’s ...
0
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0answers
6 views

What is an appropriate technique for large number of correlated predictor variables with interactions?

I want to allow the effects of a large number of continuous predictor variables to be different depending on which treatment group the individual is a part of. If I had only three continuous ...
0
votes
0answers
21 views

Longitudinal analysis of incidence rates

I am wondering how to conduct longitudinal analysis of incidence rates. A population was followed 5 years (2001-2005), and in each year "person-years" and "event" were calculated. Now I am ...

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