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32 views

Influence of TV spots on the number of visits to the website (time series problem)

I have hourly data regarding the number of visits to the website. A single record consists of date, time(0-23) and number of visits. In a separate table I have data about the display of advertising ...
0
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0answers
12 views

NLP Classification over Taxonomy [closed]

I have a massive pool of data where each row maps a user-entered description to a code that classifies the mission that the description describes. I am trying to develop a model that at least helps ...
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0answers
7 views

taking the radius neighborhoods of the points and joining them With R [closed]

I am trying to create the codes for the image below in R but failed. In short, we create their neighborhoods by taking certain radii on the points. then we connect the neighborhoods with the correct ...
1
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2answers
24 views

Sample size needed for a survey with multiple questions

I want to make a survey with several questions and conclude those results for the whole population. For example, I want to estimate the following questions for my 1 million population : "do you ...
1
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1answer
16 views

Can I conduct a weighted regression if I have one observation per year?

I am conducting a word analysis project where I find the relative frequency of a certain word over time in a corpus of film reviews. The corpus changes in size over time so someone suggested to me ...
1
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0answers
27 views

How to determine if 2 specific variables should be in the regression at the same time [closed]

I am trying to run a regression and I have two variables; income and gender. How can I determine if these 2 regressors should be in the model at the same time? Is there some sort of a test?
-3
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0answers
17 views

numpy eigenvector and eigenvalues not making sense [closed]

sorry, maybe the subject is too strong? but its driving my little brain crazy ..please look at the code below ...
1
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1answer
24 views

Is it preferable to subset data to test specific hypotheses or specify a full model and run contrasts?

Let's say I have a 2x2 design where participants are either in condition A or condition B and, within each condition, either get exposed to exposure C or exposure D. First, I want to test whether ...
1
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1answer
24 views

Correlation between nominal and ordinal variables

In my survey data I have two variables: One is an ordinal variable with 5-scale scoring from Agree to Disagree. My second variable is an nominal variable where the participants had to choose from 7 ...
1
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0answers
8 views

LR test for overlapping return data using bootstrap

I wish to test a null hypothesis as in Christoffersen (1998) to see whether a sequence of Value-at-Risk forecasts $Q_t(p) \in \mathcal{F}_t$ possesses correct conditional coverage. Here $p \in [0,1]$ ...
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0answers
26 views

Expectation and variance of order statistics (x(n)-x(1))

I saw a solution for Expectation and variance of range (x(n)-x(1)) uniform $\mathcal U(0,\theta)$ from Ben. Namely: $$f_{R_{n}}(r)=\frac{1}{2θ}⋅Beta(r2θ∣n−1,2)$$ From this expression, we get the ...
1
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1answer
15 views

Using both fixed effects and random effects in r metafor package

Hi there :) I am trying to run a meta analysis using rma.uni in the metafor package in r but cannot work out how to add both fixed effects (eg bird migration status) and random effects (eg species, ...
2
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1answer
24 views

Can I use a binary logistic regression for repeated measures data?

For this particular study, I had 3 monkeys complete 3 tasks, each task has a binary outcome (Win/Lose). A task is considered complete when they reach a criterion of 85% accuracy in their most recent ...
1
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1answer
16 views

Interpreting classification metrics for multiclass imbalance

I am at the point of reporting my results in a research article conducted. The dataset is highly imbalanced with class 1 and ...
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0answers
13 views

How to interpret cokurtosis results?

I calculated a cokurtosis matrix of the returns of multiple stocks. I obtained the following results but not sure how to interpret them. I understand that when two random variables exhibit a high ...
2
votes
1answer
58 views

Poor classification performance on a balanced dataset

I am trying to build a Stock Trend Prediction model (Target variable is 1 if the price goes up the next day and 0 if it goes down). The dataset consists 2724 samples and 60 features. Th data was split ...
1
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0answers
19 views

A question about fisher's z transformation detail of his paper published in 1921

Typically, people will use Fisher's z-transformation (arctan) to turn the r into a variable that is approximately normally distributed. When I look though his paper published in 1915(https://www.jstor....
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2answers
14 views

What model should be used for vector to scalar time series prediction

I'm new to machine learning and I'm trying to work on a problem and the data looks like the following: ...
0
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0answers
22 views

Orders of ARMA(p,q) model using ACF and PACF plots

I am trying to determine a few possible autoregressive moving average (ARMA) candidate models for a time series analysis. I have decided to look at the lags of the ACF and PACF plots; however, I am ...
0
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1answer
18 views

Combined probabilty for 1 to 6 between a cube and a dodecahedron, not counting 7 to 12

We have two dice, one with six sides (a cube) and one with twelve (a dodecahedron) The cube bears the numbers 1 to 6. The probability for each number is $\frac{1}{6}$. The dodecahedron bears the ...
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0answers
19 views

What does a straight line of residuals of a time series mean?

I used Python's statsmodels' seasonal_decompose & received the following plots: I understand that the residuals here are what is leftover after trend & ...
0
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0answers
4 views

Ordinal package - CLM. Too many variables violate proportional odds assumption - what do I do?

If too many variables show nominal effects or dealing with them causes model misspecification as shown by the Hessian value, is it OK to leave them as is in the clm and say something like “on average, ...
0
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0answers
17 views

Measuring uncertainty with bayesian neural network

One of the ways to measure epistemic uncertainty, is using bayesian inference in neural networks. The idea is to learn the posterior over the weights $P(\phi|X)$ which describe the probability ...
1
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0answers
12 views

Interpreting procrustes analysis

I am trying to find out if there is a correlation between two data sets (if one of them, which is called "varechem", depends on the other, which is called "varespec"). I ran the ...
0
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0answers
10 views

How do I calculate the cumulative probability of an observation fitted with a mixed effects model?

I am interested in getting the cumulative probability of an observation that is fitted with a generalized linear mixed effects model. For a linear model with gaussian distribution this seems simple. (...
1
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1answer
21 views

How do I calculate the correlation coefficient between these two sets of data, taking into account the uncertainty values I have for one of them?

I have two sets of data, both of which have a varying pattern pattern. I believe that one set of data (in blue in my image) illustrates the cause of the pattern which shows in the other set of data (...
1
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0answers
21 views

Concentration inequality for the sample covariance matrix

I'd like to know if there is a concentration inequality for the sample covariance matrix that don't assume the knowledge of the true mean. Background. Given a probability distribution $\mu$ on $\...
1
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0answers
9 views

Nominal effects variables - is it ok to interpret z value?

Is it appropriate to report the statistical significance of the threshold coefficients for variables in a clm model that were calculated with nominal effects? Using the example from the ordinal ...
1
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1answer
27 views

Comparisons of distributions: How to deal with discrepancies between visual impression and statistical tests (K-S, ranksum)?

I'm having some doubts how to properly compare my data (because of visual discrepancies), represented as histograms. Here's an minimal and representative example, illustrating the data: I measure BMI ...
0
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0answers
8 views

Update an existing ordinary linear regression with new data and another covariate

I am studying a case on a topic that was studied a while ago, related to food technology. To simplify the question, let's say that there are old OLS models that relate this property ($Y$) in certain ...
0
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0answers
11 views

Statistical significance of increments (treatment/control)

This is a very rookie question. I have data for three years (2018, 2019 and 2020) on income, disaggregated by treatment/control units. I want to verify whether the income has increased more for ...
0
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0answers
18 views

Find P(B) given P(A∩B), P(A^c∩B^c) and P P(A∩B^c) [closed]

I have an exam question and I don't understand how they reached the answer. The question is find P(B) given that P(A ∩ Bc) = 1/3 P(Ac ∩ Bc) = 1/2 P(A ∩ B) = 1/10 I checked the answers and there ...
0
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0answers
3 views

linear mixed model and post-hoc comparisons

I realised that this is going to be a long post. So I apologise in advance and thank everyone for taking the time. I am performing an MRI study in which I presented visual stimuli of four conditions ...
3
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1answer
33 views

How do you express the variogram $\gamma(u)$ in terms of correlation for a stationary process?

The Analysis of Longitudinal Data textbook by Diggle et al. (2002) mentioned twice (p48 f. and then on p82) that given the following definition of the variogram, \begin{equation} \gamma(u) = \frac{1}...
3
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2answers
49 views

Why important features does not correlated with target variable?

I'm testing if there is a relation between top important features and correlation between those features and target. I'm working on the titanic dataset. I plot the feature importance (using ...
1
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2answers
33 views

Model Explanation

I have a problem where I am trying to predict something from historic tabular data. We have features {X1,X2,..Xn} and I have a prediction {Y} I am trying to find a way to explain why the model came up ...
1
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0answers
7 views

What is the difference between the receptive field and a patch?

In this question and answer it is beautifully described what a patch is. What's a "patch" in CNN? However, for me, following the explanation in the link, it seems like a patch and the ...
0
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0answers
8 views

Where can raw data on New York's Covid-19 Vaccination be found? [closed]

New York State has a dashboard of vaccination progress at https://covid19vaccine.health.ny.gov/covid-19-vaccine-tracker , but I was looking to access the raw data behind the dashboard. Usually this ...
0
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2answers
37 views

How to match the distribution of one dataset when subsampling from another?

I have two datasets that measure the same variable under different conditions. The first dataset (d1) is much larger (9,000 observations) than the second dataset (d2; 900 observations). A histogram of ...
0
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3answers
77 views

Relationship between Bayes Rule and Bayesian Networks

Learning about Bayesian Networks in school - I ran across a problem which ask to find the probability of $Pr(Alarm|Storm=T)$ given a column of event data for four variables: Storm, Burglar, Cats, and ...
0
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0answers
8 views

Error message in R when applying irf function to a SVAR-model [closed]

I estimated a structural autoregressive model with the following R commands: var=VAR(dat, p=2) A=matrix(c(1,0,NA,1),byrow=TRUE,nrow=2) B=matrix(c(NA,0,0,NA),byrow=TRUE,nrow=2) svar=SVAR(x, Amat = A, ...
0
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0answers
29 views

frequency of a word that is close to itself in a list [closed]

I have 2 files where the word "test" is found 3 times each. distributed.txt this is only a test to see if test is same as test Another file has the word ...
1
vote
1answer
36 views

Intuition on Wasserstein Distance

I've been trying to familiarize myself with the Wasserstein distance and saw this answer on StackExchange by @antike that at first made a lot of sense, but then it didn't (to me, of course). In the ...
1
vote
2answers
22 views

How to measure correlation between multi-item likert scales?

I recently conducted a online survey and are now having trouble deciding for the right analysis method. For example: I wanted to see if there is a correlation between Factor A and Factor B. However in ...
0
votes
0answers
3 views

How to Forecast Quarterly Dependent variable with Monthly Independent Variables with Random Forest

I want to forecast US GDP(quarterly variable) using 100+ monthly financial and macro variables with Random Forest. My issue is that I do not quite know how to interpolate the quarterly data into ...
1
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0answers
36 views

What use is a test set in a continuous training setting?

I have tuned and trained a model that predicts an aspect of customer behavior from behavior within the most recent 12 months. After initial training, generalization performance was estimated based on ...
2
votes
2answers
57 views

Fitting a distribution like exponential but with always negative $\frac{d^2}{dx^2} \log \text{pdf}(x)$

I have some continuous data in the domain $[0,\infty]$ which I have physical reason to believe is almost, but not quite exponentially distributed. The difference between my idea of a distribution and ...
0
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1answer
12 views

How is Gaussian assumption used in proving Gaussian comparison inequality

I'm studying the HDS book by Martin Wainwright. In section 5.4.1, there is a Theorem 5.25, which is a general Gaussian comparison inequality, reproduced as follows. Let $(X_1,X_2,\dots,X_N)$ and $(Y_1,...
1
vote
1answer
22 views

Understanding math notation in infoGAN paper

I'm reading this paper about mutual information in infoGAN infoGAN_paper_link and already have the code to run it. I pretty much found code for it which is fine and dandy except for the fact that I ...
0
votes
0answers
16 views

Understanding Rayleigh Distribution

I am an aerospace enthusiast. I have obtained wind speed data that's been gathered and published by NCEP/NCAR. It provides wind speed data for every $2.5^\circ$ increment in latitude and longitude for ...

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