Questions tagged [application]
applications of statistics and statistical modeling
92
questions
11
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4
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Methodology for Reconciling "all models are wrong ..." with Pursuit of a "Truer" Model?
When attempting to model various phenomena, in practice, our model will usually be "wrong", but can still provide us with useful insights/predictions.
What methodologies can we follow to ...
1
vote
1
answer
29
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Names of actual software which use the LDA classifier
I read generic claims online and in papers that the Linear Discriminant Analysis (LDA) classifier is widely used for many applications including: face recognition, speech recognition, medical ...
0
votes
1
answer
34
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Trying to find the appropriate statistical method(s) to answer a marketing question — analyzing composition of groups
I’ve got roughly 90k rows of data, where each one represents a customer at my company. One of the columns tells me the channel that brought that customer to my company.
I’m looking at the channel mix ...
2
votes
0
answers
71
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Quote on too good to be true model performance
I seem to recall that there is a nice quote by some (well known?) machine learning expert about too good to be true model performance. The quote is something like "If your model performance looks ...
0
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1
answer
72
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Is there a certain order of steps to be taken when conducting regression analysis?
This is an extremely dumb question probably, but I took an applied regression analysis course recently and, while I feel competent enough to do regression analyses on a basic level for future projects,...
14
votes
3
answers
433
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Proper regression for determining correlations between derivatives of functions
Say we have a permanent-magnet DC motor that roughly obeys the system equation $\ddot{x}(t) = \alpha \dot{x}(t) + \beta u(t) + \gamma$, where $x(t)$ is the displacement of the rotor, and $u(t)$ the ...
0
votes
1
answer
26
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Application of transformations of lognormal distributed random variables
I'm answering questions from a book and I have to do a simple transformation Y=g(X) of a lognormal distribution:
$X \sim \mathcal{LN}(\mu,\,\sigma^{2})$ with $Y=ln(X)$
Then $Y \sim \mathcal{N}(\mu,\,\...
0
votes
1
answer
85
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How to apply Lyapunov CLT to data
I have a situation where I have around 30 classes of variables with different means and variances (though the means aren't too far from eachother; think 4-7) and that the distributions are right ...
1
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0
answers
42
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Practical use for heritability value at sub-population level?
For me as a layperson, heritability is something that much smarter people than me calculate, and there are several questions already on the forum about how to do that (eg, this and this). I ...
0
votes
1
answer
97
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Optical flow models (FlowNet) training/finetuning process
I'm reading about optical flow models, particularly FlowNet and PWC-Net. I thought I understood how training and finetuning are being done, but I don't believe so anymore after trying to understand ...
1
vote
0
answers
20
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2 boxes of money, unknown money inside, one is twice the amount of the other [duplicate]
Suppose, I have two boxes. A host is telling me to pick one. I see the money inside of this one - say 100 \$. Now, I need to decide if I want to swap, given the information that the other box has ...
5
votes
1
answer
497
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Clarifying the applications of Bayesian networks
I have been looking at Bayesian networks, using the book by Koller, Probabilistic Graphical Models. The book is very large, so I might have missed the answer to my question ;). But I was trying to ...
0
votes
0
answers
33
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Calculate probability density by function application
let's assume we have a probability density function which is $$f(X) = \frac{a}{x^a+1}$$
how can we calculate something like this: $$Y = ln(X)$$
0
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0
answers
31
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Which field of science applies the log-normal sample median distribution?
Which field of science applies the log-normal sample median distribution (i.e. the sample median distribution with samples from a log-normal parent)? I noticed that incubation periods are assumed log-...
1
vote
0
answers
45
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How to use a p-value sampling distribution?
As part of my research I have been looking into the sampling distribution of p-values. Even though p-values are on their way out, they are still used ubiquitously with the normal $\alpha$ =.05 cutoff (...
2
votes
1
answer
61
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Example of "alternating" mass function for discrete distribution
My question is related to this question on Math.SE where it was shown that there exist discrete distributions with probability mass functions that "oscillate" in a non-monotonic way over an ...
5
votes
2
answers
164
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Potential applications of a result (by Beyer et al) on distance concentration and meaningless nearest neighbors in high dimensions
My question is motivated by this question, and self-study of the paper "When is nearest neighbor meaningful?", where the authors show the following
Theorem 1: Let $X^{(d)} \in \mathbb{R}^d$ ...
2
votes
1
answer
99
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Psychology books FOR Statistics students
I can find a lot of book recommendations on Statistics for Psychology students. But can anyone suggest some good books for a Statistics student who wants to learn about applications of Statistics in ...
1
vote
1
answer
83
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What is "LASSO aggression"?
I found a paper that stated in the methods section that they ran "LASSO aggression". At first, I thought it was a funny typo but then I did a Google Search:
Google search
and found 187 sources ...
1
vote
1
answer
146
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Independence of censoring time $C$ and event time $T$ for randomised entry to a study
While reading through the textbook 'Modern Applied Statistics With S' by Venables and Ripley, I came across the following paragraph detailing the different types of censoring possible when dealing ...
4
votes
0
answers
38
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Productionize (applied) PCA to detect outlier etc. long term with new data?
I was wondering how one could use PCA in e.g. a dashboard for non Subject Matter Expert.
For example, you are quite certain that 2 PCs are sufficient based on the current data. It also makes sense for ...
1
vote
0
answers
21
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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
0
answers
19
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How biased is a statistical study in which sampling was purposely made without repeats? [duplicate]
[Cross posted on Math.SE]
It is understood in mathematical statistics that a sample (as in sampling distribution) may very well contain repeatedly the same item/subject.
In practice though, it would ...
0
votes
1
answer
170
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Are sampling distributions of any statistic used in real life statistical analyses?
I feel I am pretty good on the mathematical basis of CLT and sampling distributions.
HOWEVER:
While sources like OpenIntro Statistics (Diez et al, 2019) are fairly straighforward with their actual ...
5
votes
2
answers
221
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What apples do worms prefer? [closed]
I'm confused with some practical statistical problem, for which I have limited data and don't understand how to start with the problem. If anybody can point how such problems are (traditionally) ...
6
votes
1
answer
4k
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Can someone provide a brief explanation as to why reproducing kernel Hilbert space is so popular in machine learning?
I thought functional analysis was long thought to be old fashioned and generally a dead research area.
It seems that all of a sudden there is a huge fascination with so-called reproducing kernel ...
0
votes
0
answers
19
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Interpreting ANOVA results in the educational context
I have run an experiment in a six-week course to measure the effect of my educational treatment on student engagement. The treatment happens on weeks 4 and 6 of the course (for all of the students) ...
1
vote
1
answer
99
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Why should we study copulas? [closed]
I am new to the study of copulas and I would like that someone could provide some examples where they are applied, their usefulness and so on. Any help is appreciated. Thanks in advance.
0
votes
0
answers
40
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Summarize regression results on different datasets
I have 20 datasets (extracted from 20 different software systems) and fit a logistic regression model on each of them. On every dataset, the model was the same (same dependent variable and the same ...
42
votes
2
answers
2k
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Evidence for man-made global warming hits 'gold standard': how did they do this?
This message in a Reuter's article from 25.02.2019 is currently all over the news:
Evidence for man-made global warming hits 'gold standard'
[Scientists] said confidence that human activities ...
2
votes
0
answers
56
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How do I measure effects over years in longitudinal panel data with individuals?
I'm working with a longitudinal panel dataset that surveys the same few thousand individuals biennially and I have six years of this data. My dependent variable would be how much individuals spend on ...
3
votes
1
answer
79
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How do I learn when to apply which statistical distributions? [closed]
I am learning Bayesian modeling and having trouble keeping straight when it is most appropriate to apply the various statistical distributions beyond the basic ones like the beta, binomial, and ...
5
votes
1
answer
61
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What does this paper mean by mean square error?
I'm reading a paper about estimating fetal weight by ultrasound and other techniques. In Table 2 they give descriptive statistics, to wit: of all the examiners, the one with the highest mean square ...
1
vote
1
answer
79
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Do you know of business applications of Reinforcement Learning?
I'm looking for literature on the application of Reinforcement Learning (RL) algorithms in a business context. Most articles and examples in books on RL are about the application of RL to games (...
2
votes
0
answers
195
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Variables common to all individuals in a panel
I have been tasked with evaluating the efficiency of different marketing tools for a microfinance bank.
I have a panel of seven individuals (seven districts of Tajikistan) over 17 months.
Dependent ...
3
votes
1
answer
491
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What modeling problem does ridge regression solve?
If your modeling problem is that you have too many features, a solution to this problem is LASSO regularization. By forcing some feature coefficients to be zero, you remove them, thus reducing the ...
1
vote
1
answer
195
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Testing the scope of application of a logistic regression model
My aim is to assess whether I can apply a logistic regression that was fitted on a sample A (where I have explanatory variables and the outcomes) to a different sample B where I don't know the ...
6
votes
1
answer
689
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Difference between Stochastic Approximation (SA) and Stochastic Gradient Descent (SGD)
I understand the intended use cases for both stochastic approximation algorithms like SPSA or FDSA, and for SGD algorithms like Adam.
SPSA is intended for noisy objective functions, and Adam for ...
1
vote
0
answers
226
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Mixture of power-law distribution
I have two large sets A and B of (integer) numbers, both obtained with two different (and unknown) probability distributions $\rho_A$ and $\rho_B$.
A (also large) set C contains a proportion $p$ of ...
8
votes
1
answer
6k
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How Do You Choose The Number of Bins To Use For A Chi-Squared GOF Test?
I'm working on developing a physics lab about radioactive decay, and in analyzing sample data I've taken, I ran into a statistics issue that surprised me.
It is well known that the number of decays ...
1
vote
1
answer
143
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Population proportion inference: what statistical error am I committing here?
I am struggling to understand the following paradox.
Suppose we have a large population of people who exhibit different values of a trait, e.g. they are sick with different strains of a virus. ...
0
votes
2
answers
895
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Compare the slopes of categorical data
Hello I want to compare the slopes of the linear regression lines for the following distributions of sales figures over the years 2009 to 2017.
I want to compare the slopes of the regression lines - ...
2
votes
1
answer
345
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Real world applications of regressing complex numbers?
I recently extended a linear regression software I developed to include complex variables. It works very well but I am not familiar with how this can be used in the real world. I scoured the web to ...
5
votes
2
answers
4k
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(Practical) Applications or RNN
I have been googling for a list of practical applications of Recurrent Neural Networks for some time, but did not find a reasonable reference list.
Most of the things are about text generation which ...
1
vote
2
answers
236
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Android Recommendation App Algorithm [closed]
I have this project proposal entitled "Android Based Program Recommendation App". (This application is for those college students who wants to shift to other programs).
The app will find a program ...
1
vote
1
answer
87
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Infering relative importance of features in driving a dependent variable
In an auctions website I maintain, auctions are listed most-recent-first. There are 20 auctions per page. A user can click next in the footer to view older auctions....
2
votes
0
answers
118
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Applying machine learning to dynamic complex systems (e.g. weather prediction)
Would it be correct to say that:
Physics-based, domain specific models are more widely used and are more practical in (longer term) weather forecasts than pure machine learning approaches
The reason ...
2
votes
0
answers
80
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Practical application for theoretical sampling process
Does the following sampling process model any particular real life scenario ? If so, could you point me to some relevant scientific papers.
Consider an arbitrary probability distribution $\mathcal{D}$...
3
votes
0
answers
3k
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Finding correlations in a large dataset
My main objective is to find correlations between process parameters and their impact (more specifically: the amount of wear measured) on specific sections of equipment used in the process.
I've ...
2
votes
1
answer
65
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What statistic is appropriate to test if measured data points from untrusted sources are accurate enough?
Suppose I'm retrieving the price of asset from 3 different independent sources.
What statistic can I use to test whether data points are close enough that I can be confident they're correct?
I have ...