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### How to initialize an encoder-decoder type of neural network that is used in image segmentation?

In this example: https://github.com/qubvel/segmentation_models.pytorch/blob/dcd19d676bdfbf73fc140d5b98d780f449b0a2f8/segmentation_models_pytorch/base/initialization.py It only initializes the decoder ...
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### Does increasing the value of C in svm.LinearSVC leads to overfitting?

I have made an svm.LinearSVC model to classify images. Firstly, the features of the images are extracted by SIFT and then based on them the LinearSVC is trained. I have the following Python snippet: <...
14 views

### Why am I getting NAs in this calculation in R? [migrated]

While working on an Rcpp program, I used the sample() function, which gave me the following error: "NAs not allowed in probability." I traced this issue to the fact that the probability ...
7 views

### Implication of gaussian model with strictly positive data [closed]

On this site there are many messages underlining that a gaussian model is not the best choice to fit data that can assume just positive values such as count data, because it allows predictions to ...
4 views

### How do we define the kernel to calculate the acceptance ratio for Metropolis-Hastings Markov Chain Monte Carlo?

I am having a lot of difficulty understanding how to apply the algorithm to a real scenario. The part that confuses me is that we are looking for a target distribution (the real distribution of our ...
7 views

### How to generate several scenarios of ARIMA(p,d,q) Gaussian time series

I am wondering how it is possible to generate several scenarios of an ARIMA(p,d,q) time series with Gaussian noise and with an initial value for the start of the time series. Are there any packages to ...
7 views

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### Simple point processes and the expected value

When considering simple point processes, how is $$P(t_{n+1} \in [t;t+dt]) = E[N([t;t+dt])]$$, where $N(A)$ is the number of points in interval $A$ and $dt$ is the length of an infinitesimal interval. ...
13 views

### Please verify my RNN/LSTM multilingual multi class text classifier approach

Can you please verify my approach for a multilingual multi class text classifier using RNN/LSTM? The dataset consists of authors (labels, response) and their letters (input data). The letters can be ...
13 views

### Kernel PCA stopping rule / criterion

I have been comparing dimensionality reduction methods, while performing KPCA, I didn't know what number of PCs I should retain, how many to take and decide : "there it is, this is the new ...
12 views

### False cross validation points

So I have a practice test I am attending on K-folds and it asks me to select the false statements regarding K-fold cross validation: ...
12 views

### What is the significance of missing value correlations?

Suppose, I have a missing value correlated matrix. Some features have high correlation. What does this imply? How this insight can help me decide to handle missing value in a dataset?
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### How to calculate eigen values from a 4x4 matrix without any software? [closed]

How to calculate eigen values from a 4x4 matrix without any software? The matrix is given below, A[1,]= 19 30 2 12 A[2,]= 30 57 5 23 A[3,]= 2 5 38 47 A[4,]= 12 23 47 68
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### Testing for a linear relationship between a treatment value and outcome

Suppose there are five treatment groups, $D = 1, 2, ..., 5$, and also a control group $D = 0$. We are interested in the effect of the treatment $D$ on some outcome variable $Y$; and to this end, have ...
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Many times I differentiated the MLE of the normal distribution, but when it came to $\sigma$ I always stopped at the first derivative, showing that indeed: $$\hat\sigma^2 = \frac{\sum(y_i-\bar y)^2}{n}... 0answers 3 views ### Data lineage/traceability in pipelines I want to collect information about: 1) from which single data signals a feature is composed in a ML pipeline and 2) what data preprocessing operations are/were executed on a data signal. Does anyone ... 0answers 14 views ### Using Gaussian Process For Predicting with Confidence I have a dataset of [(cluster of points, real location point)], which contains clusters of points (x,y) and for each cluster a real location point. My goal is given a cluster of points, predict where ... 0answers 6 views ### How to conduct a mixed ANOVA with group means only? I recently came upon 2 questions about mixed ANOVA (1 within IV and 1 between IV). Having been working on it for a few hours without a clue brings me here to ask if anyone knows the solution. ... 0answers 5 views ### Is it acceptable to use Boostrap/Jackknife to estimate the variance of an MAP estimators? Suppose we obtain a point estimate using a maximum a posteriori estimator \hat{\theta}_{MAP}. Note that I'm aware Bayesian approaches generally do seek point estimates, but suppose this is an ... 0answers 10 views ### which copula function is used in financial industry [closed] There are so many copula clayton, guassian , frank , archimedian copula but which one is most used in the financial industry. 0answers 2 views ### How to combine multiple stratified sampling results? I have done a multistage sampling by first dividing the population into some strata and then using system(or simple random) sampling to sample in each stratum. I calculated the proportions or means(... 0answers 2 views ### Acceptance criteria and sample size for paired semi-quantitative data? I am trying to perform a comparison test on multiple variables, in order to compare 2 montages (A and B for example). Lots of variables are semi-quantitative, whose values are under a limit of ... 0answers 11 views ### Mixed effects model - level 2 differences Panel data, showing respondents answers across two waves; ... 0answers 11 views ### Is there a distribution that does not hurt softmax? [closed] I am using hyperopt. I generate 3 random numbers then feed it into softmax to calculate. However, if I use uniform distribution in range (1, 100) for example, if it generates (1, 1, 100) it will badly ... 0answers 17 views ### Why is the Kullback-Leibler divergence defined with a negative sign? I am aware of Gibbs' inequality, but I still want to know why the Kullback-Leibler divergence is defined with a negative sign. Here is my reasoning so far: Let X be a Bernoulli random variable with ... 0answers 10 views ### Tumour cells and ResNet A patient is represented by a set of images (1000 at maximum) of his tissues of either healthy or tumour cells. A patient is classified as 1 if at least one of the images shows tumour cells. These ... 1answer 7 views ### What test can i use for this hypothesis? It has a continous variable and a categorical variable I have two variables Financial literacy- It's a continuous variable with high and low scores Default(It means to Not pay their loan)- Yes or no (I can code this as 0 and 1) What test can I use to test ... 0answers 4 views ### WHICH weight matrix are shared in RNN and which change upon Time? In my opinion there are basically 4 weight matrix in the RNN. SO there are different names given in different scenarios but let me point out what I know about RNN in very simple terms. Please correct ... 1answer 29 views ### ML estimator of \theta>0 is \hat{\theta}_n=\frac{\sum_{i=1}^nX_i^2}{n} and I(\theta)=\frac{1}{\theta^2}. Show \hat{\theta}_n is consistent In this problem we have that I(\theta)=\frac{1}{\theta^2} is the Fisher information for a general probability density function f(x;\theta) and X_1,..., X_n are IID random variables from this ... 0answers 9 views ### Validity and Meaning of Feature Importance in Neural Networks I’m trying to identify the features of products which consumers are most passionate about through sentiment analysis of product reviews. While there are plenty of models which seem to be quite ... 1answer 103 views ### Why are means not relevant to binary variables? Trying to learn Basic Statistics from the Coursera. At the time 29 second, the video says: Means are not relevant with such a binary variable. Why? 0answers 14 views ### nested logistic regression model [duplicate] I had a dataset that consists of 20000 chess matches. In this dataset, there are columns and variables- such as the players' ratings- that might have an impact on binary data, a white player is more ... 0answers 6 views ### How to use Principal Components Analysis (PCA) to find overall orientation of polygons collectively? I was advised to use the Principal Component Analysis (PCA) to find first eigenvector which gives the direction of the first principal direction. Principal Component Analysis (PCA) is a new concept to ... 0answers 3 views ### How to get group p-value from subjects' t-values in a random effect linear model I know that for a single participant, the two-tailed p-value will follow pvalue = 2 * tcdf(-abs(t_value), dof); where tcdf is ... 1answer 18 views ### Intercept in lm() and theory not agreeing in simple linear regression example I have data y_i,x_i and the model y_i=\alpha x_i^\beta + \epsilon_i where \log{\epsilon_i} \in N(0,\sigma^2). Thus, I define z_i=\log{y_i} and w_i=\log{x_i} and my normal linear model ... 0answers 8 views ### Nested regression model I had a dataset that consists of 20000 chess matches. In this dataset there are columns and variables- variables like the players’ ratings- that might have impact on a binary result, white player ... 2answers 29 views ### Why is least squared loss sometimes written multiplied by \frac{1}{2}? The base least squares formula that makes sense to me is:$$\sum(y^{(i)}-h_{\theta}(x^{(i)}))^2$$Where h_{\theta} is the hypothesis function, y^{(i)}\in R, x^{(i)} \in R. Then sometimes I see the ... 1answer 23 views ### How to choose a model? Residual deviance or AIC I have two models of logistic regression with the same variables in the first model I got: Residual deviance: 61.097 on 73 degrees of freedom AIC: 79.097 in the ... 0answers 3 views ### Regression analysis comparison of Betas with different dependent variables I have a quite simple question but am suddenly not sure about whats correct. I have conducted two multiple regression analyses. In both analyses, I had the same predictors, but different dependent ... 0answers 6 views ### Read auto_arima summary from pmdarima package correctly [duplicate] I run auto_arima model with seasonality from pmdarima python package in the following way: ... 0answers 7 views ### Proof of Autocorrelation function property I am trying to intuitively make sense of a specific property of the autocorrelation function:$$ \lim_{\vert\tau\vert \rightarrow \infty} R_{XX}(\tau) = \bar{X}^2  where $\bar{X} = \mathbb{E}[X(t)]$ ...
Let's say $Y=\alpha + \beta x + e$ is a normal random variable, with parameters $\alpha, \beta$ and a normal error $e$. When data points $(x_{i}, Y_{i})$ are taken $(i = 1, 2, 3, ... ,n)$, then the ...