All Questions

0
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0answers
4 views

Finding covariance functions of models

Trying to calculate the covariance function for $x_t$ $$x_t = \frac{1}{3}a_t+\frac{1}{3}a_{t-1}, \space a_t \thicksim NID(0, \sigma^2_{a})$$ $$\gamma_x(0) = cov(x_t, x_t) \\= var(x_t) \\= var (\...
0
votes
0answers
6 views

Measure originality of responses

I conducted an experiment where 12 participants gave one-word answers to 10 open-ended questions. I now need to measure a creativity of responses of each participant. I tried hard but I couldn't ...
0
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0answers
4 views

How to use ExploreKit

I have read about ExploreKit and it seems the tool that I want for generating new features and selecting the best features for my target my question is how can i use this tool? is there a Python ...
0
votes
0answers
9 views

Time series application in pure-math problems

Have anyone succeeded in applying time series techniques to pure math problems? For example, maybe for some of the mysterious sequences in the OEIS, one can gain some new insight by doing some ...
0
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0answers
3 views

How does one intuitively interpret significance of splines/GAM term?

Consider the data dput here. I can predict y from x using a cubic spline: ...
0
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0answers
6 views

Choosing an optimal value of k for the KNN algorithm

I have implemented the Kth nearest neighbour algorithm for a dataset with 10 features and an output that predicts YES/NO. To choose the optimal value of k, I plotted a graph between the error values ...
0
votes
0answers
6 views

Is This the proper way to cluster ScikitLearn?

I am new to machine learning, I just finished preparing my data and started clustering it. I was wondering if the code below is the proper way to use it. ...
0
votes
0answers
9 views

Question: Comparing 2 methods to identify CNVs using WGS data

I have 2 method to find CNVs using WGS (whole genome sequencing) data. for both of them I have calculated CNV z-score for every chromosome arm. now I want to compare these 2 methods to see which one ...
0
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0answers
4 views

How to predict NaN (missing values) of a dataframe using ARIMA in Python?

I have a dataframe df_train of shape (11808, 1) that looks as follows: ...
1
vote
0answers
7 views

How do I compare time series forecast models? (ARIMA vs HoltWinter)

I'm working on a toy problem to try and get a better understanding for time series forecasting. I have a sample data set, which I'll include, that shows daily e-commerce sales from 2015 through Feb, ...
0
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0answers
3 views

Guide for Image Segmentation?

I'm working on a project regarding Image Segmentation using Deep Neural Networks, and I face some difficulties in finding papers to start with. If someone can recommend a fundamental papers that can ...
0
votes
1answer
4 views

Difference between agglomerative and divisive clustering in terms of results?

Both methods in Hierarchical clustering have always the same result (number of clusters and instances in the same clusters) and the difference is only the way they use to compute the result? Or the ...
0
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0answers
9 views

How to avoid error bars from overlapping with

I am trying to make a line plot with error bars. I have made all the changes I can to the values of width and padding and I cannot make the bars stay over the points. If I set the width of "dodge", it ...
-1
votes
0answers
5 views

Functional logistic regresion with fda or fda.usc

I have doubts about how to implement a functional logistic regression. What are the most appropriate functions and procedures to do so? Point of departure with fda package: Let's consider the ...
0
votes
0answers
9 views

“Count” intersections on an image of a grid

So given images of grids and corresponding numbers of intersections as labels, could a network learn to "count" them? You can imagine those grids like the one you have them in the game "Go". My ...
0
votes
0answers
10 views

Reinforcement Learning in Real Life/Practical Terms

In every day life, it seems that we all have various habits and actions that we perform. For example, we wake up and check our email/facebook etc. on our phones. We don't look at are current state ...
0
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0answers
4 views

Conflicting residual diagnostics for GLMM for binary data: zero-inflation

I fitted a mixed logit model with crossed random effects in lme4_1.1-21::glmer to some experimental binary data. The maximal random-effect structure justified by ...
2
votes
2answers
15 views

source of statistical uncertainties

What's the source of statistical uncertainties in measurements? I understand that random noise can be a source of the uncertainty. Also sometimes the signal itself is randomly determined. In that ...
0
votes
0answers
15 views

Ridge vs. Lasso vs. Elastic Net

I have a theoretical question. I was reading about ridge regression, lasso and the elastic net, and is very impressed. One thing is not quite clear to me. I would like to know when should I use each ...
0
votes
0answers
9 views

Improve the accuracy of semantic text matching

I have a corpus of ~200K sentences of variable length, the median length is 16 words. My goal is for a given sentence to find other sentences with a similar meaning. I tried several approaches: using ...
-1
votes
0answers
6 views

Mediation: a*b does not equal C even though c' is insignificant [on hold]

For my master thesis I am currently conducting a mediation analysis. Results indicated that there is a total effect (C is significant) and also that the a- and b-path are significant. c' on the other ...
0
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0answers
10 views

Application of oil statics in oil and gas industry [on hold]

How can I determine relationship between number of wells and annual oil production by using statics?
0
votes
0answers
5 views

Diagnostic plot of glmm model

I am very new to R and I have a problem with the diagnostics of my models...can anyone help me please? i have run my model: Modell_ia8<- glmer(vote~edu1 + age1+ female+eink1+scltrst+poltrst+...
0
votes
1answer
12 views

Softmax with Cross Entropy optimization vs Backpropagation

I am following a tutorial from Analytics Vidhya on creating a neural network to recognize handwritten digits (the classic example). The code from the tutorial states "First we need to define the ...
0
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0answers
11 views

Numerically calculating the integral of the discrepancy between the empirical and theoretical distribution functions

Having a sample of observations, $x_i, i=1,..,n$, to test the null hypothesis stating that the data follows a specific distribution $F_0 (x)$, the Cram\'{e}r-von-Mises goodness-of-fit test statistic ...
0
votes
2answers
13 views

Can independent/dependent events be thought of graphically?

My understanding is that events are subsets of the total outcomes in a sample space. So if two events are mutually exclusive, then they (the sets) do not overlap in the sample space. This can be seen ...
0
votes
0answers
14 views

How do I compare the predictive power of two predictors within a single (logistic) regression?

I've read about how F-tests can be used to compare models and to decide whether an additional variable should be included in the regression. However, I want to test whether A vs. B are better ...
2
votes
2answers
41 views

LASSO Regression - p-values and coefficients

I've run a LASSO in R using cv.glmnet. I would like to generate p-values for the coefficients that are selected. I found the boot.lass.proj to produce bootstrapped ...
0
votes
0answers
16 views

How can you contribute to solve social problems in Bangladesh by using Machine-Learning Technology? [on hold]

How can you contribute to solve social problems in Bangladesh by using Machine-Learning Technology?
2
votes
0answers
27 views

What are the main approaches to the foundation of statistics without probability

The frequentist, likelihood and, to an even greater extent, Bayesian approaches to statistics are all based on probability. Without probability, it seems difficult to use a data sample ("seen" cases), ...
0
votes
0answers
5 views

How can Shewhart individuals control chart can be apllied in oil industry? [on hold]

How can you analyse oil production data from the field by using shewhart individuals control chart?
0
votes
0answers
6 views

What does alpha in smoothing stand for

I want to apply Gaussian smoothing to a dataset and came across the smth.gaussian function in R. That besides the numerical input data requires two parameters: ...
0
votes
1answer
23 views

Am I reading my dataset right?

Since I'm new in deep learning I have some questions. I made some tests with keras and mnist dataset and everything was OK. Then I decided to try with some of my datests. You could find the dataset ...
0
votes
0answers
4 views

how to add grid pattern only above the reference line in SPSS [on hold]

I need to add grid pattern only above the reference line in SPSS. How can I do?
1
vote
1answer
13 views

Probability of getting a negative mark if one chooses options randomly in a MCQ question with negative marking

In a test with 100 multiple choice questions, a student chooses to pick an option randomly. There are four options for each questions. Answering a question correctly will give the student 1 mark, ...
0
votes
0answers
11 views

Comparing two z-score variables

Say I have 2 variables (height and weight) for 20 people. Each height and weight value will be converted into a z-score (calculated using age and gender dependent population norms). Weight and ...
0
votes
0answers
13 views

Standard error of conditional survival probability using delta method

I need to estimate the standard error of the conditional survival probability using the delta method. I fitted a kaplan meier curve for these probabilities.I know how the delta method works, I just ...
0
votes
0answers
10 views

What is the best way to reperesent this data (R)?

I am trying to show the correlations between life expectancy age and state pension age for men and women, per country. I have the following data here (working example): ...
0
votes
0answers
9 views

logistic regression manipulation [on hold]

hello guys i have a work to do of logistic regression and i'm little bit confused by the way that i must use my data i have about 19 variable and are all factor with labels ofen like yes or no so the ...
0
votes
1answer
12 views

Model selection and error estimation with active learning

I'm working on a classification problem where we have plenty of unlabelled data but it is costly and time-consuming to label them. So, I'm looking into active learning to economize on how much data we ...
0
votes
0answers
17 views

Signature of a distribution - Earth Mover distance

I am studying the Earth Mover Distance from here, but I have some difficulty in fully understanding what is the signature of a distribution and how it matches with the last constraint of the Earth ...
0
votes
0answers
2 views

How can you test whether two samples of noisy data differ by the inclusion of one (or more) signals

Tldr; I am wondering If there is a test that enables you to compare two samples A and B of data, and robustly test the hypothesis that A contains a real signal, if B is certain to contain no signal, ...
-1
votes
1answer
18 views

sum rule in conditional probability

P and S are the common cause of c. If P(C=true| P,S ) is given , can I introduce S to P(C|P) as P(C= true|P= true)= P(C=true| P =true , S= true)* P(P=true ,S=true )+ P(C= true | P=true ,S =false )*P(P=...
0
votes
0answers
14 views

Calculating the Bayes estimator given prior $\pi (\theta) = \theta^{-2}e^{-1/\theta}$?

Let $[X_i|\theta] \sim N(0,\theta)$ and suppose $\theta$ has prior distribution: $$\pi(\theta) = \theta^{-2}e^{-1/\theta}$$ I want to find the Bayes estimator of $\theta$ under square error loss, ...
0
votes
0answers
14 views

Difference between various time series models

I was just trying to fit a model on stock prices. First i tried Ar(1) model then MA(1) model then Arima(1,1) model . However the Maximum Log Likelihood of all the three models was very similar to ...
0
votes
0answers
10 views

Type of bias where useless data can discriminate

Let's say that there is a dataset $D$ of samples with domain $\mathcal{C}$ $\times$ $\mathcal{L}$, where $\mathcal{C}$ is a feature space and $\mathcal{L}$ is a binary label space ($0$ and $1$). ...
1
vote
0answers
31 views

Logistic regression with rare events

Could somebody provide some references on the application of logistic regression for modelling rare events? So far I've come across three methods with the main references below: Exact logistic ...
0
votes
0answers
2 views

Creating a statistic for The Chase quiz show

I run a website based on the UK version of this TV show. At the moment I use a simple statistic to rate a player's performance, basically the percentage of show's that they have won. But this isn't a ...
1
vote
0answers
4 views

Decomposing a random variable into marginals and copula

I’m having trouble getting understanding how to actual construct a copula, from my understanding it captures the purely joint features of a joint distribution. I’ve been working with the following ...
2
votes
1answer
28 views

p-value random effect in glmer() in lme4 package

I know that in order to test whether a random effect has a significant impact on a model it's necessary to sequentially remove one random effect at a time and check each model pair with ...

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