# Questions tagged [vector]

The tag has no usage guidance.

24 questions
Filter by
Sorted by
Tagged with
53 views

### Transformers for sales forecasting, vector output

I'm looking for a multivariable time series architecture that accepts multiple independent variables and produces multiple dependent variables. The context is sales forecasting given item, discount ...
• 2,123
10 views

Here, $\cdot$ is the dot product. Suppose we have $x_1,x_2,x_3,y_1,y_2\in\mathbb R^2$. There is a system of inequalities of the following: $$x_1\cdot y_1>0\\x_1\cdot y_2>0\\x_2\cdot y_2>0\\... • 381 1 vote 0 answers 25 views ### Uniqueness of Vectors This question is in two parts: I have a series of large vectors (where each vector comprises of values 0 and 1) that I have then concatenated into one large matrix. What I first want to know is how '... • 31 0 votes 0 answers 9 views ### Visualization of document vector in Vector Space Model with more than 3 dimensions I am studying Vector Space MOdel. It says documents are represented as vectors with every term making dimension. All examples on google present visualization of following form where there are only 3 ... • 101 1 vote 1 answer 18 views ### Accurracy for predicted vectors I am currently working on a machine learning model that yields a vector of offloading decisions. An example: [-1, 0, -1, 1, 1, 0, ...] The model does not return this vector directly. Instead, the ... • 13 0 votes 0 answers 6 views ### transformation of binary vectors I need to solve the next idea. I have a dataset with many individuals with information about an intervention every individual appears 4,5,6 or 7 times in the data set. I need to specify that If the ... • 965 0 votes 0 answers 30 views ### How are the roots of this VAR model determined? The VAR model is given with the properties below. I understand how the VAR was rewritten but how are the roots determined with the given information? • 1 1 vote 0 answers 40 views ### What is the derivative of a matrix with regard to a vector defined? I had this question when I read equation (C.20) in Appendix C of "Pattern Recognition and Machine Learning" written by Christopher M. Bishop. Here I copy the equation below for reference: ... • 183 0 votes 0 answers 56 views ### How should vector notation with multiple indices be interpret? This is a question about the interpretation of mathematical notation in statistical models. Let's say that this equation represents a panel model: y_{it} = \alpha + \boldsymbol{\beta}' \mathbf{X}_{it}... 0 votes 0 answers 19 views ### Update cointegration vector Hello everyone and thanks in advance for your interest. I have a time series of length T, and I compute the cointegration vector though the Johansen's methods over one section of the series itself, ... 2 votes 1 answer 136 views ### How do I calculate the variance of a Hermitian form? Suppose \mathbf{x}\sim\mathcal{CN}\left(\mathbf{0},\mathbf{I}_n\right) is a circular complex Gaussian random vector, and \mathbf{Q} is a Hermitian matrix. How do I calculate the variance of the ... • 23 0 votes 0 answers 232 views ### Scalar similarity measure between two vectors including both angle and magnitude I have different models, predicting a vector \boldsymbol{v}\in\mathbb{R}^3. Now I would like to compare the performance of these models against a baseline vector \boldsymbol{b}\in\mathbb{R}^3, for ... • 261 0 votes 1 answer 17 views ### Product of elements of a vector which has very large values and very low values ordered in decreasing order (MATLAB) I have to compute the product of the elements in a vector V. The elements of my vector are in decreasing order and go from very large numbers (eg 5e^5) to very small numbers (e.g 1.8e^-8). I am using ... • 147 2 votes 2 answers 387 views ### How to define distance for vector of angles? I have a vector of angles and I am looking for a method to compute the distance of my vector with any other vector of angles? I am looking for something similar to Euclidean distance but I know that ... • 151 0 votes 1 answer 57 views ### Removing duplicate training vectors? As an extension to this question, for ML problems where it makes sense to remove duplicates (ie: identical data & target variables) from your distribution, in which scenarios would it (if at all) ... • 101 11 votes 1 answer 9k views ### What is the difference between the dot product and the element-by-element multiplication? What is the different between the dot product "\cdot" and the element-by-element multiplication notation \odot in Statistics? I referred to Hamilton's Time-Series Analysis, and these ... • 1,102 1 vote 0 answers 54 views ### rank of an expected value of a matrix x is (a * 1) vector y is (b * 1) vector x and y are independent then what is rank(E[xy']) I know that xy' should be (a*b) matrix and since they are independent. , however I am not sure about the rank • 11 1 vote 0 answers 234 views ### Expected value of a product of two dependent random variables Let me preface this by saying that I'm an engineer, and by no means a mathematician, so please excuse any mathematical "wrong-doing" in my explanation. I have two vectors V_1 and V_2, ... • 11 0 votes 1 answer 175 views ### Length of a probability vector? I'm doing some work on probability vectors, and came across the idea of probability vector length as a measure of how deterministic a probability vector is, as calculated using this equation: The ... 0 votes 0 answers 37 views ### How do I take the derivative to \gamma  of (y-x^{\gamma})^T(y-x^{\gamma})? I have to solve the least squares for \gamma in the following problem. The model is described as y_i = \beta x_i^{\gamma} + u_i, where u_i  is i.i.d. normal with mean zero and variance \sigma^2... 2 votes 2 answers 694 views ### Matrix and vectors, why different notation for dimensions? If we collect data and put it into a matrix of size (100,3), we tend to say we have three-dimensional data. We think of each column as a dimension. On the other side, if we have a vector of size (100,... • 251 0 votes 0 answers 55 views ### What is the entropy of multivariate data multiplied by a vector? It is a general rule that for multivariate data \boldsymbol{X} and a matrix \boldsymbol{A}, their entropy is$$h(\boldsymbol{A} \boldsymbol{X}) = h(\boldsymbol{X}) + \ln |\det \boldsymbol{A}| (...
• 3,343
I have a little question, but I don't know that well how to answer it. I have a random walker with position vector $\vec{r} = \sum_{i=1}^N \vec{r}_i$, where i is the random walker's step. Every vector ...