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Running Simulink Model and changing parameters automatically from command window in MATLAB

I am generating fault datasets by Simulink Model in MATLAB for fault classification using Machine Learning. Everything works well with manual settings. I want to run Simulink Model directly from the ...
0 votes
0 answers
4 views

Statistically compare two algorithm outputs

I want to test the efficiency of two different algorithms. I have two random samples from the same population. On one sample, I run Algorithm X; on another sample, I run Algorithm Y. There are 30 ...
  • 1
0 votes
0 answers
2 views

Testing equality of mean responses

In the context of linear regression, we know that $E(y|x_0)$ for a given new data $x_0$ is estimated by $\hat{y_0}=x_0^t\hat{\beta}$. If given another set of new observations $x_1$, is there a way to ...
0 votes
0 answers
11 views

Forecasting at very granular level (sparse data) - how to aggregate or disaggregate?

I am trying to forecast the number of orders of laptops, which can have different combinations of features, like with x Ram, y color, z CPU, 13inc, etc, at the week level. And for this, I have my ...
  • 1
0 votes
0 answers
5 views

Difference in differences with multiple treatments

I work with a large unit-day (i,t) panel and want to estimate how the timing of treatment (A) affects the effectiveness of treatment (B), but I can't get my mind around how to do this correctly. What ...
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0 answers
8 views

Gradient Descent Algorithm: For multiple local minimum which one to pick

This might be a newbie question, but it is from a newbie. If there are multiple local minimums, and the function converges at various local minima, which local minima to pick for optimization? Do we ...
  • 101
0 votes
0 answers
6 views

Binned resampling of correlated data with bootstrap method

The goal Compute the Binder cumulant defined as the estimator $$\text{B.C.}=\frac{\langle x^4\rangle}{\langle x^2\rangle^2} $$ and its statistical error on a sample of normally distributed data points ...
2 votes
0 answers
9 views

kNN Classifier Asymptotic Error Rate versus Bayes Error Rate

Suppose we are in the realm of $M$ class classification, $M \in \mathbb{N}$. I have seen the following result stated many times, but only proven for the case $k = 1$. I would like to prove it for ...
  • 163
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0 answers
4 views

How to count number of false positives and false negatives in object detection

I've got a rather simple question for you, however to which I can't find a proper answer. Let's have a simple setting which is visualized in the image below. We've got one object of class A in the ...
  • 11
3 votes
0 answers
13 views

Remove Additive Zero Mean Gaussian Noise

I have six values, and each value is corrupted by Additive-Zero-Mean-Gaussian Noise with var = 0.05). Each value is range from 0 to 1. Is there anyway for me to remove these additive noise?
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1 vote
0 answers
8 views

What is the information plane theorem for an autoencoder neural network?

Slide 8 (about 19 minutes into the video) of the Stanford Seminar - Information Theory of Deep Learning, Naftali Tishby has the following (rather informally stated) theorem. Theorem (Information ...
  • 4,500
2 votes
0 answers
16 views

KL-Divergence on Uniform Distribution, is this correct?

P1 is uniform of [0, 0.5], P2 is uniform of [0, 1] What is the KL-divergence(P1 || P2)? Attempt: KL(P1||P2) = integral of log(1/2) = integral of log(1/2) from 0 to 0.5 = log(1/2)* 0.5 . KL(P2||P1) = ...
  • 217
0 votes
0 answers
4 views

Interpretation of the results of a multi-levek meta-analysis with metafor

I have noticed that the topic has been already threated in other questions but I am still struggling about one specific issues. In details, FC_Feedstock <- rma.mv(yi = EF, ...
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0 answers
3 views

Probability of completing a task on time given a start delay

I am trying to model the probability of completing a task in time given the scheduled time and a starting delay. In the plot below, the x-axis (deviation from schedule) is the ...
0 votes
0 answers
7 views

Creating synthetic data for time series, Hidden Markov Model

Suppose that I have a task of classifying a time series. I decide to use Hidden Markov Model $\lambda(A, B, \pi)$, where $A$ is a transition matrix, $B$ is an emission probability, $\pi$ is an initial ...
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1 vote
0 answers
13 views

Best fit line of bivariate normal data passes through extrema of level sets

I am learning about the idea of correlation in statistics, and I came across the following Statement: the best fit line of bivariate normal data passes through extrema of level sets. That is, if $(X,Y)...
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0 answers
6 views

Johnson-Neyman plots for glmer models (logistic, mixed effects) in R against non-zero values

Note: this is a different question from the one I asked here, but I'm using the same example model. I have an R glmer (logisitc mixed-effects) model that looks ...
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0 votes
0 answers
11 views

Which is the likelihood function of the logit model? [duplicate]

I'm wondering which is the likelihood function for a logit model and how I can derive it. Thanks!
0 votes
0 answers
8 views

3d hausdorff distance for GPU Pytorch [closed]

I would like to compute the Hausdorff distance between two 3d tensors in pytorch using GPU’s Do we have any inbuilt function or source code for Hausdorff distance between two 3d tensors
3 votes
2 answers
30 views

What is the 'right' slope formula of a regression? deltas or Pearson?

this may be a silly question, but still: I've been told that the slope formula equals the rise/run ratio, like this: $$ m = \frac{rise}{run} = \frac{y_2 - y_1}{x_2 - x_1} $$ in which rise equals ...
0 votes
0 answers
4 views

GLMM - are there pitfalls for modeling the error distribution independently of the variable relations?

I was running a LMM with random intercepts, as such: model1 = lmer(web ~ rain + body_size + placement + canopy + understory + (1|species)) To me the residual ...
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1 vote
0 answers
9 views

Comparing service utilization across zip codes

I work for a nonprofit and we are trying to assess utilization of our services across our service area, particularly to identify any communities to target for additional outreach. We are working with ...
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1 vote
0 answers
23 views

Can I take the p-value from a probability table for a modified z-score, just like a z-score?

I have a question regarding the modified Z-score, can I use this score in a Z-probability table, i.e. the p-value from a modified z-score? where: z-score = (xi - μ)/σ (the z-score probability can be ...
0 votes
0 answers
20 views

Does Mann-Whitney U test require equal variance or not? [duplicate]

I have already read that the test requires and also that the test does not require equal variances of the samples tested. For example: Requires: https://www.isixsigma.com/tools-templates/hypothesis-...
0 votes
0 answers
16 views

SMOTE newly generated rows

I have an unbalanced dataset on which I used SMOTE to even the classes. I'm using R and the package::function is smotefamily::SMOTE. Now, this function required numeric variables and some of the ...
  • 105
0 votes
0 answers
16 views

Newton Raphson algorithm in R [closed]

The log-likelihood function of $\boldsymbol{\theta}=\left(\mu, \sigma^2, \lambda\right)$ is $$ \ell(\boldsymbol{\theta} \mid \boldsymbol{y})=-\frac{n}{2} \log (2 \pi)-\frac{n}{2} \log \left(\sigma^2\...
0 votes
0 answers
14 views

do you need to specify the direction of b for a moderated regression

I conducted a moderated regression, but didn't specify the direction of moderation by M. that is I didnt specify whether the relationship between X and Y would be greater at lower or higher levels of ...
0 votes
0 answers
8 views

SELECTION OF MULTIVARIATE TECHNIQUE

Can someone please explain what does single relationship mean in the below image for the selection of multivariate regression techniques? In "Several dependent variables in a single relationship&...
0 votes
0 answers
6 views

How to label lines using glmnet LASSO plot with names [closed]

I have plotted the lasso glmnet as follows: plot(lasso_full$finalModel, xvar='lambda',ylim=c(-0.3, 1.6), label=TRUE) which gives a plot of all the predictor variables but it labels them as 1,2,3, etc. ...
  • 1
0 votes
0 answers
17 views

How can I back transform a log data to interpret t-test and get original CI?

I have data that is not normally distributed. I can log-transform it to be normally distributed, and then perform a t-test and get confidence intervals (CI). But how do I interpret the results of the ...
  • 11
0 votes
0 answers
4 views

Interpret the conditional Sigma (vs Realized Absolute Returns) dcc

I have estimatedenter image description here the DCC model and then plotted the model can someone help me understand how can I interpret the [enter image description here][2]Conditional Sigma (vs ...
0 votes
0 answers
7 views

Approaches for running separate monthly regressions on a time series

I have a time series with daily granularity. The time series under consideration depends on an independent variable x (say). In order to account for seasonality effects - I run a separate regression ...
0 votes
0 answers
13 views

Central limit theorem in R, exercise question from a random number dataset

I am currently trying to solve the following exercise in R with a random dataset: Calculate the means and variances of the rows of the following simulated data set, and plot the distributions of ...
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0 votes
0 answers
15 views

How to remove the correlation parameter for categorical variables with lmer

Dear CrossValidated community, could anyone help me understand what the workaround is to remove the correlation term within a linear mixed effects model random effect structure that includes ...
1 vote
0 answers
9 views

Is there anyway to calculate the integral of a trace?

I would like to calculate the integral of a scalar function as follows: $$f(x)=\mathrm{tr}((\mathbf{A}x+\mathbf{B})^{-1}\mathbf{B}),$$ where $\mathbf{A}$ and $\mathbf{B}$ are two $n\times n$ positive-...
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1 vote
0 answers
18 views

Coefficients of dummy variables in a logistic regression

I wanted to know what is the difference between running a multinomial logit regression and a logit regression on a model in which the dependent variable is a dummy with just two levels. My database ...
0 votes
0 answers
18 views

Non-nested and overlapping hypothesis testing

Consider the following non-nested and overlapping hypothesis testing: $$H_0:\;\theta\in A\quad vs\quad H_1:\theta\in B$$ where $A\cap B \neq \emptyset,\;A\not\subset B,\;B\not\subset A$. Here, we have ...
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2 votes
1 answer
12 views

Pre-Data processing categorical variables in decision tree in R (rpart)

I am new to decision trees, there are several things confused me a lot. The first thing is that should we convert all categorical variables (Such as: gender, ...
0 votes
0 answers
26 views

Interpretation of logistic regression results

I have a database that looks like this ...
1 vote
1 answer
24 views

In what sense is "Bayesian cross validation" Bayesian?

In cross validation, we repeat training the model with resampled training data and measure average of the errors from the different resampled training samples. So cross validation is basically a ...
0 votes
1 answer
13 views

Interpret the Conditional Sigma (vs Realized Absolute Returns) of the DCC model

I have estimated a DCC model and now I have plot the dcc.fit of the model and now I would like to know if someone can help me to interpret this graph as I am new to ...
0 votes
0 answers
9 views

Binomial distribution and counting analogy

There is text completion question in an exam which has 3 blanks and for each blank there are 3 options , what is the probablity that we would choose the write combination of answer? If I use Binomial ...
1 vote
1 answer
17 views

Poor auto-ARIMA predictions

I am trying to fit and forecast water production in a well and this accounts for my end of training thesis. But I got poor prediction from ARIMA and sarima models. I tried with auto ARIMA but it didn'...
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-1 votes
0 answers
9 views

find the variance of model [closed]

anyone know how we can calculate the variance of X_{T} in this case.
1 vote
1 answer
29 views

Choosing a proposal density g(x) for $ f(x)= {\Large \frac{e^{x}}{(e-1)} }$ [closed]

In finding an proposal distribution function $g(x)$ for the following function: $ f(x)= {\Large \frac{e^{x}}{(e-1)} }$ where $0 \leq x \leq 1$ Tested with $$x^2+1, 1/x+1$$ and other variations, but ...
0 votes
0 answers
10 views

How to jointly model a binary outcome with an associated confidence rating using R?

I have data of the form: judgment confidence variable A 0.8 2 A 0.7 1 B 0.2 5 B 0.3 6 Outcomes: A dichotomous variable (binary judgment) A confidence score associated with the judgment [0-100%] ...
2 votes
1 answer
32 views

Is there any well-founded way of calculating the euclidean distance between two images?

I need to determine the distance between two images. Supposing that we are dealing with images of the same size, I think that we can reduce this problem to the square root of the sum of the square of ...
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1 vote
0 answers
5 views

Method to model exponential fit line coefficients based on main function parameters

I have a quite complicated trigonometric equation I was able massage into a parametric function that takes four parameters as inputs/arguments, say: $a$, $b$, $c$, and $d$. Regardless of the ...
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1 vote
0 answers
12 views

how well would a robust mixed model fit these data? R (rlmer)

I want to investigate Y ~ X1 * X2 + (1|ID on this dataset (there's a plot of these data in that post too, it's the same dataframe) Y is a continuos outcome ...
0 votes
0 answers
8 views

Change versus level regression

I tried running a panel regression of y on contemporaneous x variables, and again using the change in y from year t-1 to year t. I am getting the opposite sign on my variable of interest (VOI) if I ...

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