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6 views

Graph node binary classification: Training set labels contain false negatives

I'm working on a graph node classification problem. Given a graph G = (V, E) where each vertex v has a set of features x, and each edge e may also have a set of features, I want to predict which (...
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0answers
6 views

Can I use a frequency distribution to encode categorical variables in a neural network?

I would like to use categorical features to an autoencoder neural network. Typically for categorical features my approach has been to one-hot encode the features to make indicator features. The ...
1
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0answers
21 views

What’s the relationship between the variables in $E[(Y-(b_0+b_1X))^2]$ and $\frac{1}{n}\sum_{i=1}^{n}(y_i-(b_0+b_i x_i))^2$ in linear regression?

From Section 1.2 and 1.3 of these notes, for some r.v. $X$ and $Y$, if $MSE(b_0, b_1) = E[(Y-(b_0+b_1X))^2]$, it was found that $\beta_1 = \frac{Cov[X,Y]}{Var[X]}$ and $\beta_0 = E[Y]-\beta_1E[X]$ are ...
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0answers
21 views

Should I trust AIC value or the p-value of linear regression model?

I have a linear model and when i run the stepwise variable selection, i got: ...
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0answers
14 views

ML model performs better on unseen data in comparison to performance on CV train — Is that a problem?

I am using Matlab to train a feedforward NN using Cross validation (CV) approach. My understanding of CV approach is the following. (Please correct me where wrong) Let ...
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0answers
17 views

Multiple testings ANOVA

Please help me to explain Why are multiple testings an issue when conducting ANOVA type models such as Two Way ANOVA? Thank you.
1
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0answers
14 views

Generalization of Bessel's correction to higher order models?

Multiplying sample variance (i.e. variance from sample mean) by $\frac{n}{n-1}$ to obtain an unbiased estimate of the population variance (i.e. variance from population mean) is called Bessel's ...
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0answers
14 views

Type-III sums of squares F-test's

I would like to know the answer and explanation: True or False? The overall Type-III sums of squares F-test's allow the analyst to determine where specific differences lie between levels of the ...
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0answers
8 views

Check when dataset should be splitted

I have a dataset where I need to say if it could be divided into two or more to help the AI to classify that dataframe. Therefore, I applied the elbow method and the silhouette to see into how many ...
0
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0answers
7 views

Meta Analysis with Likelihood Ratios

I am currently writing a protocol for a systematic review and meta analysis to analyze the available evidence regarding epidemiologic studies on risk factors for pneumonia. The end goal of the ...
0
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0answers
6 views

Expected Shortfall for ARMA-GARCH two day forecast

I need to find the 99% confidence expected shortfall (CVaR) for a long position of 100 dollars at time $t$ for an asset with returns modeled by an ARMA(1,1)-GARCH(1,1) model with $r_t = θr_{t−1} + u_t ...
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0answers
4 views

Difference in analysis between latent and observed variables in Mplus

I would like to ask what is the difference between the analysis being run on latent and observed variables in a full SEM being run in Mplus. I've been recommended to change the factors within the CFA ...
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0answers
6 views

Intervention analysis and prediction variance in Arima

When fitting time series data with Arima, if you perform an intervention analysis, you put regressors in which, I think, are explanitory variables for things like outliers and mean shifts. If you do ...
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0answers
9 views

Distributions with Rational PGFs that are closed under addition

Are there any probability distributions that have rational pgfs, such that adding two random variables of the distribution yields a random variable that follows the same distribution?
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0answers
9 views

Hypothesis testing using non-independent distributions drawn from the same model

The explanation that follows is a simplification but preserves the key details (I hope). I am working on a problem related to hypothesis testing using results from a numerical hydrodynamic model of ...
2
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0answers
10 views

Python Machine Learning: Measuring confidence in individual classifications

I am pretty new to machine learning. I am currently using sci-kit learn's DecisionTreeClassifier and RandomForestClassifier to look at astronomical data. It takes in a number of parameters and tries ...
2
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0answers
25 views

How to interpret coefficient for rq()

Suppose my prediction equation code is: model = rq(y ~ a+b+c+d+a:b, data=df) I used quantile regression. and I obtain the coefficient: ...
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0answers
6 views

How to determine statistical significance between two proportions from different time periods?

Background: Customer satisfaction (1 to 5 Likert scale) with a particular service is measured via an online survey that is ran during a 15-day period each fiscal quarter. Simple random sampling is ...
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0answers
10 views

Delta-gamma neutral portfolio [closed]

I am trying to solve this exercise. Knowing that delta01 =-2, delta 02=0.5, gamma 01=0.2 and gamma 02=-0.2 and our delta-gamma neutral portfolio contains 10 stocks find its structure.
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0answers
8 views

What route is best for comparing diversity between 2 different sites

I am considering fungi presence and diversity in two different forest sites and looking for correlation between fungi presence/diversity and forest health. I am very new to stats, basically know ...
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0answers
15 views

Differences between the lm(), lqs(), and rq() function

In R, we can use the build-in function lm() for linear regresson. However, we also use the lqs() function from ...
0
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0answers
10 views

Artificially increase sample size with VAE samples

I want to apply a statistic (KL) on (moderate) high dimensional data and therefore need a lot of data. As its not given, I want to create additional samples that are alike the original data but not ...
0
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0answers
6 views

Implementing Procrustes rotation for factor scores, and least damaging alternatives

I am hoping to use multiple imputation to deal with missing continuous data (measured on a scale of 0-100) before conducting exploratory factor analysis (EFA), and to obtain factor scores for each ...
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0answers
9 views

How do I make a Chi square test for distance and time? [closed]

Im confused please give me some advice?
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3answers
22 views

is probability defined on outcomes or events (or both)?

studying myself and trying to understand probability foundations, and I find that even books do not agree, or probably I do not understand. What I have learned: Outcome: what can happen in an ...
2
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2answers
63 views

(Linear regression) Can I train and validate at the same time using the following approach?

In a lot of material I found online, training and validation seems to be an iterative process For example, the regularized regression problem $E = \|Xw - t\|_2^2 + \lambda \|w\|^2_2$ $X$ is data ...
1
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0answers
17 views

Possible to work backward from Convolution of Distributions?

So, having discovered distribution convolution, which is a method for deriving the density of a sum of individual probability distribution densities, $$S = X_{first\_distribution} + Y_{second\...
2
votes
1answer
43 views

Bernoulli distribution p-value shortcut

I am trying to evaluate the impact of a hypothetical treatment that has a binary outcome (adverse health event or no event). I have ten thousand of simulated "studies". I want to quickly identify ...
0
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0answers
11 views

Would OLS be just as good as OLR for analyzing this survey?

I want to use a regression in survey analysis, to determine the extent to which a variety of ordinal (and a few nominal) independent variables predict a variety of ordinal dependent variables. My ...
0
votes
1answer
14 views

Derivations of Forward and Reverse KL Divergence equations

In the Forward KL, the entropy has disappeared and in the Reverse KL, the entropy has a plus sign, why are they so?
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0answers
10 views

Two-way repeated measures ANOVA vs mixed ANOVA

I collected data from 50 patients at 3 different time points and performed analysis using 3 different methods. What would be a more appropriate test to compare the measurements between time and ...
1
vote
1answer
27 views

In making scatterplot for correlations between two continuous variables, can we use the choice cubic instead of linear choice [closed]

In making scatterplot for correlations between two continuous variables, can we use the choice cubic instead of linear choice in "create a fit line at total", as shown in the copied Figure, please? ...
0
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0answers
10 views

Maximum entropy correlated prior

This question arose from trying to think about Kaggle's Titanic passenger survival prediction challenge from a probabilistic perspective. Say I'm trying to model a simplified version where the only ...
0
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0answers
28 views

Time Series: If $X_t$ is independent N(0,1) and $Y_t$ independent Uniform($-\sqrt{2}, \sqrt{2}$)

I am trying to find the autocorrelation function between $X_t$ and $Y_t$. Any insights into this would be super helpful.
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0answers
5 views

MFCCs and mean normalization

I'm reading a blog about extracting MFCCs features for Machine Learning applications, but I didn't understand the following points about the mean normalization: To balance the spectrum and improve ...
0
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2answers
37 views

How important is p-value in Machine Learning?

Scikit-Learn doesn't exhibit the p-values for your models. I'm used to look at the p-values - besides a few other factors - when choosing the variables to consider on my final model. However, p-values ...
0
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0answers
4 views

How to create linear user embedding from some answers to binary questions?

I have each user U_i answering 10 binary questions out of a pool Q with either answer 1 or 2. I would like to learn an embedding of user profiles based on these answers to predict is answer to other ...
0
votes
1answer
24 views

p-values near 1.000 for all tests in a glm() (count and binary data, Poisson and binomial distributions)

I want to run multiple GLM's to answer a few questions about changes in diet between species and over time. Questions: Does frequency of occurrence (FO) of pieces eaten differ between species or ...
1
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0answers
13 views

How do we know adding an uncorrelated variable to a regression will not change existing coefficients?

Say I have a regression with 3 independent variables and I decide to introduce a 4th variable and rerun the regression. A previous post states that the coefficient on an original variable will change ...
0
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2answers
21 views

Different PCA scores using prcomp and eigen in R

I have data with 6 rows and 4 columns. My data are assigned to variable data. I wanted to calculate PCA using eigen function ...
0
votes
0answers
6 views

Friedman's test with different # of answer choices

Greatly appreciate your help! I am analyzing paired data across 3 groups. Data within each group is ordinal (number of genes recommended for genetic testing, with each answer choice corresponding to ...
0
votes
1answer
23 views

Clarification of the stepwise regression analysis : Bidirectional elimination

I am working on a large dataset (2000 patients, 100 variable) My purpose is to identify the influence of the variable (VarX1, VarX2, VarX3,…..) on a dichotomial outcome (VarY). My purpose is to ...
0
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0answers
11 views

Finding a distance/similarity function for vectors in a space with weighted dimensions and correlations of dimensions

I have a multi-dimensional vector space with many millions of 'event vectors' $[c_1, c_2, c_3 ... c_i]$. All of them have a respective outcome vector which has much less dimensions: $[o_1, o_2, o_3]$. ...
1
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0answers
15 views

Web application with model results for use in healthcare?

Often in medicine we use scores, so the patient gets 1 point for this symptom, another for this etc. and a final a score determines their risk/treatment strategy. If we have reliable data and build a ...
0
votes
1answer
20 views

How can I use R Studio to make a high dimensional X matrix of my predictor variables [closed]

I am working on a problem that has a sample size of 40, and 200 variables in my data set (Including my Y vector). I am just wondering how I can use R to make an X matrix using all my given columns, ...
-1
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0answers
12 views

I need help with my Epidemiology test problems [closed]

We got examples of test problems that are going to be on our exam so can anybody please help me with them. Thanks in advance This is a cohort study about the effect of high BMI on developmet of ...
0
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0answers
12 views

Can I Use Lagged Indep Vars to See Endogeneity in 2SLS FE

Can I use lagged explanatory variables as instrument variables to figure out if the variable at question is endogenous when I use 2SLS FE estimation (in Stata: xtivreg2)?
0
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0answers
9 views

Generate an Index in Stata [closed]

I want to create an Index (Average Air Pollution per Child) and have the following information (see picture) I need to calculate the average air pollution (given per year) for each child. An example:...
4
votes
1answer
62 views

What's the added value of SD line over regression line when examining association between 2 variables?

I'm trying to incorporate different practices to use when exploring a new data set. Especially, how to examine the association between two variables. Steps for example (not necessarily by order): ...
0
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0answers
4 views

Merging data with unmatching observations

I have a few datasets related to marketing. In one of the datasets I have daily data together with sales. In other dataset I have marketing cost also per day. But my problem is that in my third ...

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