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How to deal with possibly important predictors omitted during the building of an OLS multivariate linear regression model?

I am building a descriptive model using OLS multivariate linear regression. I have a couple dozen candidate predictors, but only around 200 cases. Since I wanted at least 10 cases / variable for the ...
jorvaor's user avatar
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0 answers
2 views

Autocovariance of the product of two time series (not necessarily independent, uncorrelated or multi-variate gaussian)

I am working with time series that are the product of two other time series that may be related to one another so. In each case: \begin{equation} f_t = x_ty_t \end{equation} and I want to find the ...
hydrologist's user avatar
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3 views

Is there a way to create a SEM from multiple datsets?

I have two datsets of information on a certain plant species, for which I would like to check if they are correlated. One datset is of visitor (pollinator) frequencies to a plant species along an ...
Dominik Anyz's user avatar
0 votes
1 answer
8 views

How can I prove monotonicity of slope MLE in EIV regression model?

I'm trying to figure out Casella and Berger Exercise 12.4(c), regarding monotonicity of the maximum likelihood estimator of the slope of an errors-in-variables regression model. The goal is to show ...
narwahl's user avatar
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1 answer
11 views

Questions on Basic Data Cleansing For Linear Regression

I'm following some tutorials on doing some linear regression and as I was building my notebook, I'm working on outlier detection and amongst the techniques described for doing outlier detection, one ...
joesan's user avatar
  • 143
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11 views

Getting statistically significant differences of observation patterns

First let me start by saying that if I knew a little more about statistics, I think I would likely be able to find a solution to my problem. However you'll have to forgive me as I'm unsure as to how ...
donkey's user avatar
  • 51
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0 answers
9 views

How to solve this Bayesian expression question about car sensor? [closed]

At each time step t, sensors return the list of exact positions of the K cars, but the list of positions is shifted by a random number of indices (with wrap around). For example, if the true car ...
sarah smith's user avatar
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0 answers
6 views

In R, when presenting data (RCT) in a table (preferably gtsummary), how to include tests of significance both within group and between groups? [pic] [closed]

I am learning how to analyse the data and present the results of an RCT using R. I have tried reading the package documentation, and searched online but did not find a solution for this. I have 2 ...
Muhammad Aaqib Shamim's user avatar
1 vote
1 answer
11 views

Why does the sufficient statistic for the bivariate normal not imply a sufficient statistic for the correlation under bivariate normality?

This question links to a document by Jon Wellner that defines the sufficient statistic for the multivariate normal (p. 7, Example 2.7). The result follows from the factorization theorem and is proven ...
virtuolie's user avatar
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1 vote
0 answers
12 views

Sales data trend

I have my historical sales data and I want to check for the trend (increase, decrease or no change). When I do my annual line graph, the slop of my linear equation is positive (indicating increase) ...
monique's user avatar
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Model training loss always converge to 1.35

I'm trying to create a multi-class classification model using RNNs. The input data has a sequence length of 90 and consists of 5 features, normalized to the [0,1] range. Here's the network ...
Mangi222's user avatar
1 vote
0 answers
19 views

Jackknife variance estimate for a regression model for two subpopulation

Consider a regression model for two subpopulations \begin{align} Y_i&=X_i+\epsilon_i, i=1,\ldots,n/2\\ Y_i&=-X_i+\epsilon_i, i=n/2+1,\ldots,n \quad(1) \end{align} where $\{X_i\}$ are i.i.d. ...
Fangzhi Luo's user avatar
1 vote
0 answers
21 views

hierarchical regression in R with heterocedasticity

I performed a hierarchical regression in R using lm. I evaluated the assumptions with statistics and visually, using the performance package. Visually, I observe heteroscedasticity, although Breuch-...
María Victoria Ortiz's user avatar
0 votes
0 answers
3 views

Creating a model to predict costs from multiple variables over the course of years [closed]

so I have a data set of breakdowns in any given month and the total cost of product lost as a result each month. This data set spans over years I wanted to create a model that will relate these two ...
shahzaib asim's user avatar
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0 answers
15 views

Normal Distribution on a Line Segment [closed]

Let $h_{old}^{1}$ and $h_{old}^{2}$ be our initial line segment. and we have points $r_{old}$ that is uniformly distributed on this line segment. We change one of the vertices of the old line ...
Rust32627's user avatar
0 votes
1 answer
12 views

Help Needed: Sales Forecasting with Exogenous Variables and Small Sample Size

I'm working on a thesis using Google Trends data to predict sales revenue in a retail context. I'm using exponential smoothing and SARIMA as univariate baseline models for the sales data only. For the ...
Typeand19's user avatar
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5 views

Is the confusion matrix meaning the same within deep learning than within hypothesis testing?

Is the confusion matrix meaning the same within deep learning than within hypothesis testing? I've read what the matrix is, and how to get the values. But in the case of deep learning for ...
Mah Neh's user avatar
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1 vote
0 answers
46 views

Bayesian Statistics vs. Frequentist Statistics for Uninformative Uniform Priors [duplicate]

I have a really basic question about Bayesian statistics. Lets say you have an uninformative prior that you know comes from a uniform distribution. Is there any benefit to using a Bayesian approach ...
StrangerX's user avatar
2 votes
1 answer
64 views

What is the interpretation of alpha and beta within the plots of a H0 and H1?

Reading about statistical power they draw this: and say: Illustration of the power and the significance level of a statistical test, given the null hypothesis (sampling distribution 1) and the ...
Mah Neh's user avatar
  • 71
0 votes
0 answers
18 views

Using ANOVA with proportional data

I know this has been discussed in various questions but I have not come to a conclusion. Following scenario: I have two groups: an intervention group and a control group. Both do some sort of pre test ...
Tim Buktu's user avatar
  • 101
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0 answers
9 views

Negative Multinomial CDF implementation does not match simulation [closed]

I am trying to calculate the win probability for the following game: A player rolls a 6 sided die. If the player rolls a 1, then they get a "penalty". If they accumulate 5 total penalties, ...
ZPears's user avatar
  • 11
4 votes
1 answer
74 views

VGAMs/VGLMs vs Multiple GAMs/GLMs

I am self-studying Vector Generalized Linear/Additive Models (mostly) via Yee, T. W. (2015) "Vector Generalized Linear and Additive Models: With an Implementation in R." I think I am ...
TJM's user avatar
  • 143
1 vote
0 answers
15 views

why we need use covarience matrix to calculate eigenvectors and eigenvalues in pca [duplicate]

I am stuck at understanding the idea behind using covariance matrix for calculating eigenvectors and eigenvalues and select the eigenvector which has highest eigenvalue
daadkfjd's user avatar
2 votes
2 answers
163 views

Does the null hypothesis need be a statement of no difference?

I'm just trying to self-learn the basics of statistics. And I don't understand completely the null vs alternative hypothesis. What I don't understand is: can the null hypothesis be a statement with ...
Mah Neh's user avatar
  • 71
0 votes
1 answer
18 views

One sided likelihood ratio test for a logistic regression model?

I need to run a one-sided test on one parameter of a logistic regression model: $H_0$: $\beta = 0$ $H_1$: $\beta \geq 0$ I want to avoid Wald-equivalent methods as these are known to have problems ...
Mohan's user avatar
  • 877
1 vote
0 answers
9 views

Problems using custom dataset using Minirocket classification [closed]

I'm working on a bigger school project, trying to classify timeseries measurements with Minirocket/Rocket. My trainingdata consists of a 1D matrix containing the measurements, and a seperate 1D matrix ...
Michael's user avatar
  • 11
1 vote
1 answer
25 views

Can/should a scientific paper simultaneously perform one-sided hypothesis testing and a two-sided confidence interval?

Let's say you wish to perform a one-sided hypothesis test in which you want to reject $H_0: \Delta \leq 0$ in favor of $H_1: \Delta >0$. You select this hypothesis test specifically because you are ...
NovicePatience's user avatar
2 votes
0 answers
17 views

Centering two level-1 variables to create interaction term before multilevel analyses? Thank you [duplicate]

I like to ask for some kind help from the readers here. I have a specific question on creating the interaction term from two level-1 variables before even running the multilevel analyses. Do you mean-...
Jomel NG's user avatar
1 vote
0 answers
29 views

Random sample and its underlying sample space [duplicate]

A random sample of size $n$ is a random vector $X=(X_1, ..., X_n)$, where all $X_i$ are i.i.d., and are measurable functions on some sample space $\Omega$. Let's say, $\Omega = \{H,T\}$, i.e., heads ...
jose89's user avatar
  • 11
1 vote
0 answers
14 views

Understanding ARMA model fit

I fit an ARMA(1,1) model using statsmodels in python to a univariate data series and got seemingly very significant fit. Log likelihood: 200,000 AIC/BIC/HQIC: -400,000 AR.L1 : 0.1 (z 45) MA.L1: -0....
dayum's user avatar
  • 613
1 vote
0 answers
40 views

How to use a multi-linear regression to forecast meaningful values

I have built a multi-linear regression model based two predictors $P_1$ and $P_2$ to predict $Q$: $$ q = A + Bx_1 + Cx_2 + Dx_1^2 + Ex_2^2 + Fx_1*x_2 $$ where $x_1$ and $x_2$ are the ...
StatsNewbie0's user avatar
4 votes
1 answer
160 views

Rasmussen Equation 5.9

Can any one add the steps showing how Rasmussen (Gaussian Processes for Machine Learning, the MIT Press, 2006) got from line 1 to line 2 of equation 5.9. (pg 114)? It is calculating the gradient of ...
Snowy Baboon's user avatar
1 vote
0 answers
10 views

How to estimate a feasible Generalized Error-in-Variable Model (combine deming regression/TLS and f-generalized least squares)

I have observational data with spatial structure. A hypothetical dataset could be brain mass for 100 species of birds and body mass for those same species. The data has spatial structure because ...
A Friendly Fish's user avatar
0 votes
0 answers
10 views

SVM Kernel to compare histograms as input vectors

In lecture 7 of CS229 by Andrew Ng he mentions at the very end a specific Kernel that allows an SVM to "classify" how similar two histograms are, such as the demographics of 2 countries. He ...
yyyLLL's user avatar
  • 33
0 votes
0 answers
20 views

time series squared forecast evaluation

I have a time series with very weak autocorrelations- mostly unforecastable. However, its squared values have stronger autocorrelations. Something like this: ...
dayum's user avatar
  • 613
0 votes
0 answers
5 views

best way to determine relative rarity through probability of each new price value in an evolving time series data set as related to the empirical rule [closed]

I am working with stock market time series data where I am looking at segments of data in 30 minute intervals at different time spans, often 2-8 days in length. I have marked different historical ...
lvbx9's user avatar
  • 1
0 votes
0 answers
20 views

Given a biased coin and two people disagreeing on the chances of heads, how can one tell which is "correct?" [closed]

Suppose we have a biased coin. Person A says the coin has 60% of landing on heads. Person B says the coin has 67% chances of landing on heads. How can a third person decide who is "correct?" ...
Maximal Ideal's user avatar
2 votes
0 answers
18 views

Is it valid to exhaustively test all possible combinations of features to find the best combination?

I have about 1000 labelled observations from about 50 subjects responding physiologically under different situations and am trying to classify the situation (usually into three classes of roughly ...
user1596274's user avatar
0 votes
0 answers
17 views

Can I do a meta-analysis of categorical outcomes by assigning them to ordinal values in single-arm studies?

I have a collection of case reports and single arm cohort studies (without control groups) that describe the clinical response of patients treated with a particular drug. The response is reported ...
mortal1877's user avatar
0 votes
0 answers
9 views

What is the average number of students looked at for a quantitative education study? [closed]

On average, how many students are looked at for a quantitative education study?
new guy's user avatar
1 vote
0 answers
22 views

Estimate the probability that a crack length exceeds a threshold value after N cycles

The length $a$ of a crack after $N$ fatigue cycles $N$ is $$a(N;C,m) = \left(a_0^{\left(1-\frac m 2\right)}+ C\left(1-\frac m 2\right)B^mN\right)^{\frac{2}{2-m}}$$ where $a_0$ is the initial crack ...
DeltaIV's user avatar
  • 18.1k
0 votes
0 answers
17 views

How to measure the strength of relationship

I want to use a univariate $x$ to predict univariate $y$. Both are individually approx normal time series. When I run OLS of $y$ on lagged values of $x$, I get significant t-stat (~5) but low R2 (< ...
dayum's user avatar
  • 613
0 votes
0 answers
10 views

Are observations of different plots of the same farmer independent for a chi-squared test?

I have a pretty basic question. I have a dataset that has surveyed say 1000 farmers and their demographic data, and also surveyed the agricultural practices they undertake on each of their plots. Only ...
cha116's user avatar
  • 1
0 votes
0 answers
18 views

How can I have methods such as ORB, SSIM, VGG16 check the similarity rate according to the graph's regions? [closed]

I have an empty graph with only axes as shown in the figure: empty graph Mathematically, this graph consists of 4 parts (four part). Even though the plots drawn are the same in terms of angles, size, ...
doqukan's user avatar
0 votes
0 answers
16 views

Cut-off based on an ordinal variable in unbalanced panel data

I am currently looking for an appropriate statistical analysis for my research questions. I have a continuous variable (score) and an ordinal variable (test). Score is quadratically related to Test, i....
a.henrietty's user avatar
2 votes
0 answers
28 views

Reference request for the existence of minimal sufficient statistics

I'd like a recent paper or book that shows in what conditions we can guarantee the existence of a minimal sufficient statistic. I know the paper "Sufficiency and Statistical Decision Functions&...
rfloc's user avatar
  • 121
2 votes
1 answer
81 views

Estimate Standard Errors Effortlessly [closed]

I have an unobserved variable $𝑧_𝑖$, and three observed estimates of it: $𝑤_𝑖, 𝑥_𝑖, 𝑦_𝑖$. The errors $𝑤_𝑖−𝑧_𝑖,𝑥_𝑖−𝑧_𝑖,𝑦_𝑖−𝑧_𝑖$ are zero mean, independent of each other and ...
ba yes's user avatar
  • 21
0 votes
0 answers
5 views

coef/vcov not consistent with basis matrix [closed]

I am trying to run a non-linear Distributed Lag Non-Linear Model (DLNM) with data structured using the nested case-control methodology, incorporating five lags (years 1-5). Each case has exactly two ...
Nitzan Sagie's user avatar
0 votes
0 answers
21 views

About the derivative of the conditional Rényi entropy [migrated]

Preliminary considerations: In the paper unifying framework of information measures the conditional exponential entropy (see equation 29) is defined as: \begin{equation} \mathcal{E}_{\alpha}(X|Y) = ...
Upax's user avatar
  • 99
0 votes
0 answers
23 views

How to improve probability distribution fitting

I am trying to fit a distribution to daily percentage returns, and have got the following, where the p-val is low, suggesting it was not normally distributed. However, it's not perfect, and I try to ...
Wong's user avatar
  • 47

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