File Name: basics of statistics and probability .zip
Sign in. R andom Experiment A random experiment is a physical situation whose outcome cannot be predicted until it is observed.
See it in your library. Valid Thru. Full name. You'll need an account to access this in our app.
Sign in. R andom Experiment A random experiment is a physical situation whose outcome cannot be predicted until it is observed. S ample Space A sample space, is a set of all possible outcomes of a random experiment.
R andom Variables A random variable , is a v ariable whose possible values are numerical outcomes of a random experiment. There are two types of random variables.
D iscrete Random Variable is one which may take on only a countable number of distinct values such as 0,1,2,3,4,……..
Discrete random variables are usually but not necessarily counts. C ontinuous Random Variable is one which takes an infinite number of possible values. Continuous random variables are usually measurements.
P robability Probability is the measure of the likelihood that an event will occur in a Random Experiment. Probability is quantified as a number between 0 and 1, where, loosely speaking, 0 indicates impossibility and 1 indicates certainty. The higher the probability of an event, the more likely it is that the event will occur.
Example A simple example is the tossing of a fair unbiased coin. C onditional Probability Conditional Probability is a measure of the probability of an event given that by assumption, presumption, assertion or evidence another event has already occurred. For Independent events A and B below is true. The probability of getting any number face on the die is no way influences the probability of getting a head or a tail on the coin.
C onditional Independence Two events A and B are conditionally independent given a third event C precisely if the occurrence of A and the occurrence of B are independent events in their conditional probability distribution given C. In other words, A and B are conditionally independent given C if and only if, given knowledge that C already occurred, knowledge of whether A occurs provides no additional information on the likelihood of B occurring, and knowledge of whether B occurs provides no additional information on the likelihood of A occurring.
I choose a coin at random and toss it twice. If C is already observed i. E xpectation The expectation of a random variable X is written as E X. In more concrete terms, the expectation is what you would expect the outcome of an experiment to be on an average if you repeat the experiment a large number of time.
V ariance The variance of a random variable X is a measure of how concentrated the distribution of a random variable X is around its mean. Discrete Probability Distribution : The mathematical definition of a discrete probability function, p x , is a function that satisfies the following properties.
This is referred as Probability Mass Function. Continuous Probability Distribution : The mathematical definition of a continuous probability function, f x , is a function that satisfies the following properties.
This is referred as Probability Density Function. J oint Probability Distribution If X and Y are two random variables, the probability distribution that defines their simultaneous behaviour during outcomes of a random experiment is called a joint probability distribution. Joint distribution function of X and Y ,defined as. It means for every possible combination of random variables X, Y we represent a probability distribution over Z.
There are a number of operations that one can perform over any probability distribution to get interesting results. Some of the important operations are as below. Marginalisation This operation takes a probability distribution over a large set random variables and produces a probability distribution over a smaller subset of the variables. This operation is known as marginalising a subset of random variables.
This operation is very useful when we have large set of random variables as features and we are interested in a smaller set of variables, and how it affects output. For ex. The set of input random variables are called scope of the factor. For example Joint probability distribution is a factor which takes all possible combinations of random variables as input and produces a probability value for that set of variables which is a real number.
Factors are the fundamental block to represent distributions in high dimensions and it support all basic operations that join distributions can be operated up on like product, reduction and marginalisation. Factor Product We can do factor products and the result will also be a factor. Every Thursday, the Variable delivers the very best of Towards Data Science: from hands-on tutorials and cutting-edge research to original features you don't want to miss.
Madison Hunter in Towards Data Science. Christopher Tao in Towards Data Science. Getting to know probability distributions. Cassie Kozyrkov in Towards Data Science. Terence Shin in Towards Data Science. Sara A. Metwalli in Towards Data Science. Gregor Scheithauer in Towards Data Science. Jan Zawadzki in Towards Data Science.
About Help Legal.
The binomial distribution is used to represent the number of events that occurs within n independent trials. Possible values are integers from zero to n. Where equals. In general, you can calculate k! If X has a standard normal distribution, X 2 has a chi-square distribution with one degree of freedom, allowing it to be a commonly used sampling distribution.
distributions are similar to (but slightly different from) those used to specify continuous prob. distributions. An Introduction to Basic Statistics and Probability – p. 11/.
This class was beneficial to me because in some of the areas it forced me to think outside of what I already know an in other areas it forced me to rethink the way I was seeing situations. The International Statistics Program has developed a training course on Civil Registration and Vital Statistics CRVS Systems to provide information to epidemiologists, statisticians, demographers, and others working in public health about vital statistics data gathered from a national civil registration system. The objective of this sequence is to transmit the body of basic mathematics that enables the study of economic theory at the undergraduate level, specifically the courses on microeconomic theory, macroeconomic theory, statistics and econometrics set out in this syllabus.
Introduction to descriptive statistics. It consists of a sequence of bars, or rectangles, corresponding to the possible values, and the length of each is proportional to the frequency. These worksheets and lessons will help students learn to tackle statistics word problems that include a form of conditional aspect. That probability is 0.
This book offers an introduction to concepts of probability theory, probability distributions relevant in the applied sciences, as well as basics of sampling distributions, estimation and hypothesis testing. As a companion for classes for engineers and scientists, the book also covers applied topics such as model building and experiment design. Contents Random phenomena Probability Random variables Expected values Commonly used discrete distributions Commonly used density functions Joint distributions Some multivariate distributions Collection of random variables Sampling distributions Estimation Interval estimation Tests of statistical hypotheses Model building and regression Design of experiments and analysis of variance Questions and answers. Designed for students in engineering and physics with applications in mind. Proven by more than 20 years of teaching at institutions s.
students acquire a sound mathematical foundation in the basic techniques of probability and statistics, which we believe this book will help.
Probability and Statistics are studied by most science students, usually as a second- or third-year course. Many current texts in the area are just cookbooks and, as a result, students do not know why they perform the methods they are taught, or why the methods work. The strength of this book is that it readdresses these shortcomings; by using examples, often from real-life and using real data, the authors can show how the fundamentals of probabilistic and statistical theories arise intuitively. It provides a tried and tested, self-contained course, that can also be used for self-study. A Modern Introduction to Probability and Statistics has numerous quick exercises to give direct feedback to the students.
The student uses statistical representations to analyze data. What is the probability of picking: a a red marble? Helped Fermat solve the dice problem how many times one must throw a pair of dice before one expects a double six. Sample Problem. There are many great graduate level classes related to statistics at MIT, spread over several departments.