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Questions related to Statistical Learning
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Please write me pro and contra arguments! 
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Predictive Processing Theory proponents are like Intelligent Design theorists. They think a single metric (prediction error, ID -> God) can explain how the brain works.
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I conducted a study titled 'The Impact of AI Integration in Statistics Learning on Student Motivation and Learning Engagement in the Higher Education Sector.' The results indicate improvements in student motivation and engagement. Could these findings represent an initial step toward enhancing overall academic performance? I would appreciate your insights.
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Yes, integrating AI applications can significantly enhance student performance. AI provides personalized learning, instant feedback, and adaptive study plans tailored to individual needs. It helps automate administrative tasks, allowing teachers to focus on student engagement. Additionally, AI-powered analytics identify knowledge gaps, improving learning outcomes. However, its effectiveness depends on proper implementation and student adaptability.
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I possess a series of comprehensive course notes dating back to 2018, each spanning approximately 130 pages. These notes delve into the mathematical aspects of understanding statistical learning. The lectures are tailored for Master's degree students and were delivered by S. Mallat at the Collège de France. Despite being the sole author, Professor Mallat has validated these notes. I believe that sharing them on ResearchGate would enhance their visibility. Please advise if this is feasible.
Best regards,
J.E Campagne
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I have used French HAL repository.
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Chalmers in his book: What is this thing called Science? mentions that Science is Knowledge obtained from information. The most important endeavors of science are : Prediction and Explanation of Phenomenon. The emergence of Big (massive) Data leads us to the field of Data Science (DS) with the main focus on prediction. Indeed, data belong to a specific field of knowledge or science (physics, economy, ....).
If DS is able to realize prediction for the field of sociology (for example), to whom the merit is given: Data Scientist or Sociologist?
10.1007/s11229-022-03933-2
#DataScience #ArtificialIntelligence #Naturallanguageprocessing #DeepLearning #Machinelearning #Science #Datamining
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Yes, data science is considered a science because it involves systematic methods, processes, and algorithms to extract knowledge and insights from structured and unstructured data, grounded in principles of statistics, mathematics, and computer science.
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In search of latest statistical theory which is backing up the machine learning algorithms.
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Day to day enhancements
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I'm looking for an algorithm that computes the VC dimension of a given hypothesis class H but I'm still unable someone that is "code-ble". The objective is to compute the minimum size of data needed to achieve PAC learning with a supervised learning model and for a given precision ε and a confidence δ.
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Hamza Ba-mohammed The VC dimension of a hypothesis class is a measure of the class's complexity. It informs you how many points the class can "shatter," or perfectly categorize. The VC dimension is significant because it indicates how well a learning system can generalize from training data to unknown data.
The "shattering" approach is a popular method for calculating the VC dimension of a hypothesis class. This is how it works:
1. Begin with an empty set of labels and an empty set of points.
2. Consider adding a new point to the collection.
3. See whether there is a method to apply labels to the other points in the set so that the new point is accurately categorized for each potential label for the new point. If so, add the point to the set. If there isn't, quit and return the size of the largest set you could build.
Here's some code to show the shattering method:
def shatter(H, points):
if len(points) == 0:
return True
for p in points:
for label in [0, 1]:
if not any(H.classify(x, label) == y for x, y in points):
return False
return True
def VC_dimension(H, n):
for i in range(1, n+1):
if shatter(H, [(x, y) for x, y in itertools.combinations(range(n), i)]):
return i
return n
The shatter function is defined first, which takes a hypothesis class H and a collection of points as input and returns True if the hypothesis class can shatter the points and False otherwise.
The VC dimension function then iteratively attempts to shatter sets of points of increasing size, beginning with the empty set and ending with a set of size n. The VC dimension function returns I if the shatter function returns True for a set of the size I otherwise, the method returns n.
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What are the best methods to handle Imbalance data? and Do these methods make more biasness?
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1.Under-sampling
2.Over-sampling
3.Ensemble learning
4.Adjusting class weights
5.The right evaluation metrics
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I have a dataset with 19 training points and 6 testing points.
At first I defined the rules for 19 training sets and then tried making predictions for the rest of 6 points. But I got all constant values.
Then when I added 6 more rules, I started getting the values which were very close to the actual values.
My question is do I have to define the rest 6 rules too? Because if I do that then it undermines the intuition of "Testing".
Or do I have to reduce the levels for output Data? Because I have created 5 levels for the output data (Extremely low, Low, Medium, High, Extremely high)
Any help would mean a lot!
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The rules are defined during the training phase so that they can be used during the testing phase, since test samples are considered to be unknown.
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In Statistical Learning Theory, Uniform convergence means for a hypothesis class H, given m(\delta, \epsilon), for arbitrary distribution over domain (X, Y), with probability $1- \delta$, the generalization error is within $\epsilon$ range.
Now The no free lunch theorem state that one can construct a distribution over (X,Y) such that an algorithm will fail with large probability while another algorithm will work. The sample size is m smaller than half of cardinality of X.
My question is: are the two statements contradictory? If the uniform convergence hold, algorithm A working on hypothesis class H will always work as long as the sample complexity is reached, so there would not be cases of failure?
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Possibly, yes
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I wonder if there is any explanation that which of statistical learning or machine learning may work better and what is reason for that.
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Random forest
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Bayesian updating and and Bayesian networks are used in so many machine learning algorithms, but can we consider them as machine learning techniques? and if we can, under what circumstances? and in what kind of applications?
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The root of Bayesian inference are in statistics, even if nowadays it is legitimately considered part of the broader field of data science, since the border b/w statistics and machine learning/statistical learning is blurred. If you want to draw a line, we can say that Naive Bayes is the typical approach of machine learning, rather than classic statistics, since in the former less assumptions (eg on the independence of predictors) are made, while in the latter assumptions are stronger (eg variables must be independent etc.). Still, the naive approach gives good results empirically , given that data are large.
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Suppose we deal with a dataset with different kind of attributes (numeric and nominal) and binary class. How can we find a unique number as the shannon entropy of this dataset (as a presentation of kolmogorov complexity of this dataset)?
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Can we use Shannon Entropy to measure 'consensus' of the various statements/questions in a Delphi study?
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Is there any literature that focuses on design of the classifier theoretically, without considering metrics.
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no
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The Big Data revolution promises to transform how we live, work, and think by enabling process optimization, empowering insight discovery and improving decision making. The realization of this grand potential relies on the ability to extract value from such massive data through data analytics; machine learning is at its core because of its ability to learn from data and provide data driven insights, decisions, and predictions. However, traditional machine learning approaches were developed in a different era, and thus are based upon multiple assumptions, such as the data set fitting entirely into memory, what unfortunately no longer holds true in this new context. These broken assumptions, together with the Big Data characteristics, are creating obstacles for the traditional techniques. Consequently, this paper compiles, summarizes, and organizes machine learning challenges with Big Data. In contrast to other research that discusses challenges, this work highlights the cause-effect relationship by organizing challenges according to Big Data Vs or dimensions that instigated the issue: volume, velocity, variety, or veracity. Moreover, emerging machine learning approaches and techniques are discussed in terms of how they are capable of handling the various challenges with the ultimate objective of helping practitioners select appropriate solutions for their use cases. Finally, a matrix relating the challenges and approaches is presented. Through this process, this paper provides a perspective on the domain, identifies research gaps and opportunities, and provides a strong foundation and encouragement for further research in the field of machine learning with Big Data.
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thank you
merci
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I need a reference to the integral analogue of Cauchy-Binet identity, but I can not find such a reference. Could you please help me? Thank you in advance.
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Dear Viera
Thank you very much for your detailed answers to my questions. Now I have increased some knowledge about pronounciation in Russian and the like. I will cite the reference by [1] above.
Moreover, if I could use the Cauchy-Binet (Binet-Cauchy) formula to complete a previous draft on the logarithmic concavity for the Riemann Zeta function, I would acknowledge you and others, who ever gave me a hand, in the final work.
Best regards
Feng
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If the data for the classes is imbalanced what are the best machine learning algorithms and will he choice vary in the case of binary and multi-class classification
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In general, it is not possible to determine beforehand the best learning algorithm for a task (a corollary of no free-lunch theorem), as this depende on data and algorithm characteristics. There are some learning algorithm which may be less sensitive, but this is a general guide, and you must find an algorithm which fits you data well. Some treatment methods may help. See our paper:
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Does anyone have a graphical representation/explanation of the difference between ANOVA, ANCOVA, MANOVA and MANCOVA?
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In ANOVA AND ANCOVA there is one continuous dep. variable. In ANOVA all the predictors are dummies while in ANCOVA some predictors are dummies and some(the covariates) are cont. MANOVA and MANCOVA are the same except they have more than 1 cont. dep. variable. Best Wishes.
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is it possible to use statistical learning to get results on thermodynamics, heat transfer, and fluid dynamics,  ... etc,, some phenomenons are still complicated and without experiments, there is no way to get their results.   
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In these cases, careful use of dimensional analysis can simplify the problem greatly. For instance for the drop time of a dripping tap. Inertia, surface tension and viscosity can all be important. Calculating the relevant dimensionless gorups shows which of the competing forces are actually important under a given set of conditions.
I can imagine that you are right and that Principal Component Analysis could be applied to some big data sets to find the effective number of variables.
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Hi researchers!  I am a learner of statistics learing and machine learning. After applying the Convolutional neural networks into image recognition and text mining, I think this method is powerful in classification.  So I want to apply them into statistics field and want to know the advantages and disadvantages of CNNs. Can I view it as a specia kind of "regression", which is blessed with flexible model form and interaction form? What is the disadvantage of it? Thank you very much!
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Recommend you to read the review paper "Deep Learning" in nature 2015.
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If any reference material please provide to me
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The suggested books may help you.
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How can machine learning or statistical learning techniques be used in association rule mining?
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Alternatively, you can use R software (www.r-project.org) and its "arules" package. If you are interested in fuzzy association rules, you can use also the "lfl" package.
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Regarding the problem of graph coloring, is there any good reference dialing with the VC dimension of the problem ?
More generally: concerning NP-complete problems, is there any good reference dealing with the VC dimension of such problems ? 
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Dear Prof.  Andriy O. Borisyuk(Borysyuk) !
Many thanks for your suggestion !
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In Galit Shmueli's "To Explain or Predict," https://www.researchgate.net/publication/48178170_To_Explain_or_to_Predict, on pages 5 and 6, there is a reference to Hastie, Tibshirani, and Freedman(2009), for statistical learning, which breaks expected square of the prediction error into the two parts of a variance of a prediction error and the square of the bias due to model misspecification.  (Variance - bias tradeoff is discussed in Hastie, et.al. and other sources.)   
An example of another kind of variance bias tradeoff that comes to mind would be the use of cutoff or quasi-cutoff sampling for highly skewed establishment surveys using model-based estimation (i.e., prediction from regression in such a cross-sectional survey of a finite population).  The much smaller variance obtained is partially  traded for a higher bias applied to small members of the population that should not be very much of the population totals (as may be studied by cross validation and other means).  Thus some model misspecification will often not be crucial, especially if applied to carefully grouped (stratified) data.
[Note that if a BLUE (best linear unbiased estimator) is considered desirable, it is the estimator with the best variance, so bias must be considered under control, or you have to do something about it.] 
Other means to tradeoff variance and bias seem apparent:  General examples include various small area estimation (SAE) methods.  - 
Shrinkage estimators tradeoff increased bias for lower variance. 
Are there other general categories of applications that come to mind? 
Do you have any specific applications that you might share? 
Perhaps you may have a paper on ResearchGate that relates to this.
Any example of any kind of bias variance tradeoff would be of possible interest.
Thank you.
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I am looking for the materials where applications of methods in statistical learning in hydrology is explained.
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Hi, maybe you look this link 
Also I have attached "Word file" for you
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I am interested in studying students reasoning while learning a measure of variation and how making connections to the measures of center can improve retention. How is variation, more specifically the Mean Absolute Deviation (MAD) taught in sixth grade, and has there been any research that might be related?
I don't yet have a clear hypothesis, but a muddy one might be  that a group provided with extended relational instruction (where connections are made between a measure of center and the MAD by both computing the MAD as a percentage of the measure of center as well as computing an expected range of values) will perform better on posttest and retention evaluation assessments for center, variation and proportional reasoning than another group (with the same teacher) who are provided with computational reinforcement for their additional instruction time. 
It seems most instructional material I have seen (NC Mathematics "How MAD are you and LearnZillion.com for example) has the student compute the MAD, but not connect or relate it to to the center by computing an expected value range or expressing it as a percentage.
Thanks in advance for your assistance!!! 
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Hi Sheri,
I am not convinced that 10 and 11 year old students need to learning about Mean Absolute Deviation. From my perspective they should be embedding the concepts of expectation and variation rather than working on statistical measures which will likely be meaningless to the mathematical contexts in which they find themselves. Regards, Kevin.
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I was wondering if anyone has any good suggestions for solving the filtering problem when you have a hidden Markov model where the hidden chain x_k has a very large state space? By very large I mean that the exact solution (http://en.wikipedia.org/wiki/Forward_algorithm) becomes too computationally demanding.
My application is basically a discrete spatio-temporal model where for each time instance the transition probability is a Markov random field with nearest neighbour interaction.
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Hi everyone, back from Easter break. Thanks for all the answers, I'll review them more carefully and make a more detailed answer later.
To give some context to the problem I am trying to solve we have recently proposed a new particle filter/sequential Monte Carlo framework that does seem to work for quite a bit higher dimension than standard PFs. I have attached our arXived paper on the matter, the type of problems I am looking to find something to compare our method with is in Section 6.3. In this filtering problem we are looking at a structured state space where at each time step we would have to sum over 2^600 or 2^1056 different values using brute force.
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The aim of probability predication is to predict pages to be dirtied in the next iteration by taking into account its previous history using probability table in virtual machine environment. Can we consider this problem analogous to time series analysis? I am also interested to know whether statistical learning is already used by someone or not? Please indicate.
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Which are good cloud computing Journals? I would like to get detail about 5-5 SCI and non-SCI (unpaid & good) cloud computing journals?
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I'm not a statistician. Just an interested MD. So, please, suggest somethitng relatively understandable. WinBUGS, e.g., is out of question. It has to have GUI, not only a command line. I have some expirience in Object Pascal and Java but not much. I'd appreciate any advise for beginner. I'm planning to start with observational longitudinal data (register and survey) and, maybe later, move towards network meta-analysis.
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I use GeNIe/SMILE (University of Pittsburgh).
SMILE is a fully platform independent library of C++ classes implementing graphical probabilistic and decision-theoretic models, such as Bayesian networks. SMILE is released as a dynamic link library (DLL). There are also several SMILE wrappers, such as SMILE.NET (.NET interface - very good), jSMILE (Java interface) etc. Versions available for Windows, Unix (Solaris), Linux, Mac etc.
GeNIe environment for the creation of decision theoretic models. Main features are graphical editor to create and modify network models and the SMILE Engine. You may develop models in GeNIe and create a custom interface for them using SMILE. 
System have thorough and good documentation.
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Bayesian statistics has been applied to a language change modeling (ex Niyogi & Berwick 1995, Griffiths & Kalish 2007 etc). I am looking, however, for any research that implemented Bayesian statistics to actual linguistic data, ex. a diachronic or synchronic linguistic variation. I would greatly appreciate any suggestion or advice, as I am hoping to use (hierarchical-)Bayesian model on historical categorical data in my thesis. Thank you!
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Hej,
within
Analyzing Linguistic Data: A Practical Introduction to Statistics using R Paperback – March 17, 2008
by R. H. Baayen (Author)
you will find first steps analysing your data with R using GLMM in combination with MCMC and literatur to go further..
Sven
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Price-elasticity models do not fit here (since they need previous/historic data with price changes to 'learn' the effect).
We have sales-data for different items (with no price-changes till now). Business owners are thinking of changing the prices for the first time, and would like to estimate the customer reaction. (Customers are not tracked, anonymous and opportunistic).
Any pointers on the right approach (R package) ?
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without any further information, there is no way to accurately forecast how the volume of sales will change when the price changes.
So, there are two things you can do:
1. if you have substitute products for which you know their elasticity, you can extrapolate the sales volume of your product in question based on the computed elasticity of the other substitute product.
2. If you don't have data for substitute products (or, you don't think good substitutes exist in your market), then you can perform a small market-research, i.e. ask a number of customers if they would be willing to buy the product in question at a smaller or higher price, and compute demand elasticity from this market research.
3. Or, you may try limited-time only incremental discounts, and see how the market moves, and based on this information, compute the elasticity of your product.
4. In general, if your sales seem to be declining as time goes by, it's a good indication that your price is too high for the current market segment you have targeted, and you need to lower prices. On the other hand, discounts, if done carelessly, will only "buy sales", but may very well cause you to actually lose money -maybe due to logistics and/or supply chain management issues that your sales campaign will bring forth, and so on... there are several studies that have documented this effect.
None of the above is related to R, or MATLAB, or Java, or FORTRAN, as they are simply methods you have to resort to, to compute an approximation of the product's elasticity. Also you need to remember that elasticity is not a static concept, but varies with time, and many other parameters. What may seem as a good bargain price to your customers today, may seem way too much to them tomorrow, so this information needs to be constantly updated.
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In K-mean clustering, every data point is being clustered. The data points which are supposed to be treated as noise are also considered in clusters. Is there any possible way to reduce such noise or a hybrid of K-mean clustering?
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Hi Anupam -
I'm not sure what you mean by "data points which are supposed to be treated as noise" - did you create them, or do they just appear to be noisy ?
data that doesn't fit nicely in to any class may be noise; or may be a new / previously undiscovered class ...
I'll describe my understanding of AutoClass briefly as it applies to your question, but go to the above sources :) AutoClass implements a hybrid K-means with individual observations assigned probabilities of being in each cluster. The number of clusters is automatically determined; and, the sense of distance is automatically determined (each cluster has its own measure of distance, based on mean and standard deviation of the observations assigned to the cluster).
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\begin{equation*} \quad min_{M,C_1,C_2}\frac{1}{N_T N_L} \sum_{\substack{ 1\le i \le N_T\\ j s.t. f_l(z_i,z_j)=1 m}}V(M,z_i,z_j)+\beta\|M\|_F^2 \end{equation*} \begin{equation*} \qquad \space \qquad \quad s.t. \qquad V(M,z_i,z_j) = \begin{cases} [C_1-d_M(x_i,x_j)]_+ & \text{if } l_i \neq l_j \\ [d_M(x_i,x_j)-C_2]_+ &\text{if } l_i = l_j \end{cases} ,\qquad \end{equation*}
\begin{equation*} \quad , \qquad \end{equation*} \begin{equation*} \qquad \qquad \quad \qquad M_{i,j}\geq 0, \qquad 0 \leq i,j \leq dim(M) \end{equation*}
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I can recommend the package Rsolnp for solving constrained (non-)linear problems. You can define equality and inequality constraints as well as upper and lower bounds for the parameters.
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I am looking for a classifier that will give us an error bound (expected performance) on test data. Also, we should not assume the data is independent and identically distributed) or features have any particular distribution. Any suggestion is appreciated.
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Learning from non-IID data: Theory, Algorithms and Practice
ECML 2009 LNIID Workshop
7 September 2009, Bled, Slovenia
(proceedings available on-line)
Ingo Steinwart, Andreas Christmann
Los Alamos National Laboratory; University of Bayreuth
Fast Learning from Non-i.i.d. Observations
Abstract : We prove an oracle inequality for generic regularized empirical risk minimization algorithms learning from $\a$-mixing processes. To illustrate this oracle inequality, we use it to derive learning rates for some learning methods including least squares SVMs. Since the proof of the oracle inequality uses recent localization ideas developed for independent and identically distributed (i.i.d.) processes, it turns out that these learning rates are close to the optimal rates known in the i.i.d. case.
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How can final set of features be selected from multiple rank lists obtained by different ranking method?
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It's a hard problem, but a simple solution might work well. This paper looked at a range of different methods in one context (ranked gene lists from microarray experiments) and found that the mean of the ranks was as good as anything else, and was reccomended due to the ease of computation:
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What are the parameters (parameters of the model) that may influence a Bayesian neural network?
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Khinchine's inequality gives me an upper bound on the r.h.s. of (sum_i x_i^2)^(1/2) but I found nothing about the stronger equality being true though the numerics suggest it.
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It depends...
Let s_i be Rademacher variables (+/-1 with P=1/2) and x_i real numbers. We want to calculate the expectation and investigate whether or not it is true that
(*) E[ | sum_i s_i * x_i |] = max{ | x_i | }.
First consider the case of 2 terms. Without loss of generality let 0 < x_2 < x_1. Note that
(i) prob(s_1=1,s_2=1) = 1/4, (ii) prob(s_1=1,s_2=-1) = 1/4,
(iii) prob(s_1=-1,s_2=1) = 1/4, (iv) prob(s_1=-1,s_2=-1) = 1/4
Then investigate |s_1*x_1 + s_2*x_2| for all 4 possible cases
(i) x_1 + x_2 >0, (ii) x_1 - x_2>0, (iii) -(-x_1 + x_2)>0, (iv) -(-x_1 - x_2)>0
Thus we can calculate
E(|s_1*x_1 + s_2*x_2|) = 4*x_1 * 1/4 = x_1 = max(x_1 , x_2)
and the claim (*) is proven for N=2.
Now take 3 terms and without loss of generality 0 < x_3 < x_2 < x_1 (if not, just re-label variables). We have to distinguish two cases
(A) x_1 - x_2 > x_3
In this case (A) we can boil everything down to our 2-dimensional case,
(s_1*x_1 + s_2*x_2) + s_3*x_3
because in the "worst case" we have x_1- x_2 - x_3, but that is positive (and likewise vice versa with minus sign). So here the claim also holds here.
(B) x_1 - x_2 < x_3
If we solve the |.| we have to consider 8 cases for the s_1, s_2 and s_3. After some calculations using the new probabilities of 1/8 we end up with
E(|s_1*x_1 + s_2*x_2 + s_3*x_3|) = (x_1 + x_2 + x_3)/2
which is not equal the maximum x_1 and the general claim is false here.
I think your claim holds true in a certain region of the hypercube of dimension N. All we need to do is to investigate 2^N possible cases for |s_1*x_1 + s_2*x_2 + ... + s_3*x_N| , where x_1>x_2>...>x_N. My guess is that for the hierarchy of inequalities
x_1 - x_2 > 0
x_1 - x_2 - x_3 > 0
x_1 - x_2 - x_3 - x_4 > 0
...
we are on the safe side. However, the effect of violating the inequalities further down the hierarchy seems to be only a small perturbation (looking at some numerical simulations). And maybe if we have two or three maximum outliers in the data, x_1, x_2 and x_3 sufficiently large versus the rest of the data and satisfying (A), the claim holds approximately true regardless.
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I am wondering whether deep learning can give better results than boosted models.
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This is not exactly what your asking for, but check out
Mitchell, Ben, and John Sheppard. "Deep Structure Learning: Beyond Connectionist Approaches." Machine Learning and Applications (ICMLA), 2012 11th International Conference on. Vol. 1. IEEE, 2012.
They demonstrate "the impact of the deep architecture itself" using only linear methods.
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Related to sequence learning and reactivation
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usually, short memory reactivations fail to induce reconsolidation, while long reactivations induce extinction. I think that the reactivation time lenght necessary to induce reconsolidation depend on the kind of memory (and its strenght and age), the kind of reactivation (mismatch or match) and species.
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In research, I have a set of random forests which are generated from a given set of datasets. Now I would like to calculate the description size (based on the MDL method proposed by Quinlan) of each of these random forests. Do you have any idea how I can calculate it?
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Thanks Oliver and Paul
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I have four variables which are correlated to each other, thus should I do partial correlation to find correlation between any two random variables with other two control variables?
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If two variables, X & Y, are correlated with a third Z, they may be related to each other simply because they are related to the third variable. It may bo of interest to know if there is any correlation between X and Y that is NOT due to their both being correlated with Z. To do this you calculate a partial correlation.
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Since random forest includes a bunch of random decision trees, it is not clear when we say forest size, it can be :
1) number of bits it takes
2) number of decision trees included in forest
3) accuracy
4) execution time
5) a manifold of all of above terms
6) etc.
What is the most important and what is the best?
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Answer
To answer a question about most important and/or best one needs to know the goal. For example, if I was going to use a random forest in an adaptive controller with 512 bytes of RAM, representation bits would be a very important design constraint. If my random forest were to be embedded into a real-time system, execution time would be key. Medical diagnosis would usually maximize some sort of risk-weighted accuracy and sacrifice other criteria.
To summarize: depending on the application different measures will be important.