In mathematics, the word null (from German: null meaning "zero", which is from Latin: nullus meaning "none") is often associated with the concept of zero or the concept of nothing. It is used in varying context from "having zero members in a set" (e.g., null set) to "having a value of zero" (e.g., null vector). In a vector space, the null vector is the neutral element of vector addition; depending on the context, a null vector may also be a vector mapped to some null by a function under consideration (such as a quadratic form coming with the vector space, see null vector, a linear mapping given as matrix product or dot product, a seminorm in a Minkowski space, etc.). In set theory, the empty set, that is, the set with zero elements, denoted "{}" or "∅", may also be called null set. In measure theory, a null set is a (possibly nonempty) set with zero measure. A null space of a mapping is the part of the domain that is mapped into the null element of the image (the inverse image of the null element). For example, in linear algebra, the null space of a linear mapping, also known as kernel, is the set of vectors which map to the null vector under that mapping. In statistics, a null hypothesis is a proposition that no effect or relationship exists between populations and phenomena. It is the hypothesis which is presumed true—unless statistical evidence indicates otherwise. (Wikipedia).
From playlist Unlisted LA Videos
Definitions of null space, injectivity, range, and surjectivity. Fundamental theorem of linear maps. Consequences for systems of linear equations.
From playlist Linear Algebra Done Right
Null points and null lines | Universal Hyperbolic Geometry 12 | NJ Wildberger
Null points and null lines are central in universal hyperbolic geometry. By definition a null point is just a point which lies on its dual line, and dually a null line is just a line which passes through its dual point. We extend the rational parametrization of the unit circle to the proj
From playlist Universal Hyperbolic Geometry
Null space of a matrix example
In today's lecture I work through an example to show you a well-known pitfall when it comes to the null space of a matrix. In the example I show you how to create the special cases and how to use them to represent the null space. There is also a quick look at the NullSpace function in Ma
From playlist Introducing linear algebra
Linear ODE with Constant Coefficients: The Homogenized Equation
https://bit.ly/PavelPatreon https://lem.ma/LA - Linear Algebra on Lemma http://bit.ly/ITCYTNew - Dr. Grinfeld's Tensor Calculus textbook https://lem.ma/prep - Complete SAT Math Prep
From playlist Partial Differential Equations
In this video I start to discuss the idea of the null space of a matrix. In these situations, the right-hand side of all the equations in the linear system is equal to zero. There is the trivial solution, where all the elements of the solution is zero. We are more interested in the spec
From playlist Introducing linear algebra
Empty Graph, Trivial Graph, and the Null Graph | Graph Theory
Whenever we talk about something that is defined by sets, it is important to consider the empty set and how it fits into the definition. In graph theory, empty sets in the definition of a particular graph can bring on three types/categories of graphs. The empty graphs, the trivial graph, a
From playlist Graph Theory
Null Space: Is a Vector in a Null Space? Find a Basis for a Null Space
This video explains how to determine if a vector is in a null space and how to find a basis for a null space.
From playlist Column and Null Space
A road to the infinities: Some topics in set theory by Sujata Ghosh
PROGRAM : SUMMER SCHOOL FOR WOMEN IN MATHEMATICS AND STATISTICS ORGANIZERS : Siva Athreya and Anita Naolekar DATE : 13 May 2019 to 24 May 2019 VENUE : Ramanujan Lecture Hall, ICTS Bangalore The summer school is intended for women students studying in first year B.A/B.Sc./B.E./B.Tech.
From playlist Summer School for Women in Mathematics and Statistics 2019
Linear Algebra Comment: Reusing the Same Letter in Different Expressions
https://bit.ly/PavelPatreon https://lem.ma/LA - Linear Algebra on Lemma http://bit.ly/ITCYTNew - Dr. Grinfeld's Tensor Calculus textbook https://lem.ma/prep - Complete SAT Math Prep
From playlist Part 1 Linear Algebra: An In-Depth Introduction with a Focus on Applications
What is a hypothesis test? The meaning of the null and alternate hypothesis, with examples. Overview of test statistics and confidence levels.
From playlist Hypothesis Tests and Critical Values
Reflections and projective linear algebra | Universal Hyperbolic Geometry 15 | NJ Wildberger
Reflections are the fundamental symmetries in hyperbolic geometry. The reflection in a point interchanges any two null points on any line through the point. Using the projective parametrization of the circle, we associate to the reflecting point a 2x2 projective matrix. So we need to devel
From playlist Universal Hyperbolic Geometry
Support Vsauce, your brain, Alzheimer's research, and other YouTube educators by joining THE CURIOSITY BOX: a seasonal delivery of viral science toys made by Vsauce! A portion of all proceeds goes to Alzheimer's research and our Inquisitive Fellowship, a program that gives money and resour
From playlist Knowledge
Chapter 8.1: Foundations of Hypothesis Testing
Chapter 8.1 from "Introduction to Statistics, Think & Do" by Scott Stevens (http://www.StevensStats.com) Textbook from Publisher, $29.95 print, $9.95 PDF http://www.centerofmathematics.com/wwcomstore/index.php/thinkdov4-1.html Textbook from Amazon: https://amzn.to/2zJRCjL
From playlist Statistics Lecture Videos
Colloquium MathAlp 2018 - Patricia Bouret
Erreurs et Tests statistiques : Un test statistique est un outil très puissant pour prendre des décisions, cependant ils sont parfois très mal interprétés. Après une petite introduction historique qui montrera que les débats autour de ces notions remontent à Fisher, je me focaliserai su
From playlist Colloquiums MathAlp
Apollonius and polarity revisited | Universal Hyperbolic Geometry 13 | NJ Wildberger
Armed with explicit formulas for null points and null lines, along with their meets and joins, we return to the polarity of Apollonius with which we began this series. Our aim is to establish a fundamental fact that was previously stated without proof: that the dual or polar of a point can
From playlist Universal Hyperbolic Geometry
Sergiu Klainerman - 1/4 On the Mathematical Theory of Black Holes
https://indico.math.cnrs.fr/event/3463/ The gravitational waves detected by LIGO were produced in the final faze of the inward spiraling of two black holes before they collided to produce a more massive black hole. The experiment is entirely consistent with the so called Final State Conjec
From playlist Sergiu Klainerman - On the Mathematical Theory of Black Holes
Overview of null hypothesis, examples of null and alternate hypotheses, and how to write a null hypothesis statement.
From playlist Hypothesis Tests and Critical Values