mean and variance of binomial distribution examples

In probability theory, the expected value (also called expectation, expectancy, mathematical expectation, mean, average, or first moment) is a generalization of the weighted average.Informally, the expected value is the arithmetic mean of a large number of independently selected outcomes of a random variable.. That is, $X\sim B(6, 0.25)$. \end{aligned} If the random variable is denoted by , then it is also known as the expected value of (denoted ()).For a discrete probability distribution, the mean is given by (), where the sum is taken over all possible values of the random variable and () is the probability This special form is chosen for mathematical convenience, including the enabling of the user to calculate expectations, covariances using differentiation based on some useful algebraic properties, as well as for generality, as exponential families First, calculate the deviations of each data point from the mean, and square the result of each: variance = = 4. There are (relatively) simple formulas for them. Definition of Binomial Distribution A discrete random variable $X$ is said to have Binomial distribution with parameters $n$ and $p$ if the probability mass function of $X$ is \mu =E(X) &= n*p\\ First, calculate the deviations of each data point from the mean, and square the result of each: variance = = 4. Imagine, for example, 8 flips of a coin. &= \binom{6}{4} (0.25)^{4} (0.75)^{6-4}+\binom{6}{5} (0.25)^{5} (0.75)^{6-5}\\ In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. \end{aligned} The neg_binomial_2 distribution in Stan is parameterized so that the mean is mu and the variance is mu*(1 + mu/phi). &= \binom{10}{4} (0.35)^{4} (1-0.35)^{10-4}\\ Specifically, the interpretation of j is the expected change in y for a one-unit change in x j when the other covariates are held fixedthat is, the expected value of the In probability theory and statistics, the Poisson distribution is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time or space if these events occur with a known constant mean rate and independently of the time since the last event. (If all values in a nonempty dataset are equal, the three means are always equal to &= 0.0374 The formula for the mean of a discrete random variable is given as follows: E[X] = x P(X = x) Discrete Probability Distribution Variance &= \binom{6}{6} (0.25)^{6} (0.75)^{6-6}\\ It is also known as the expected value. For example, we can define rolling a 6 on a die as a success, and rolling any other Given that $p=0.35$ and $n =10$. & & \qquad \; x = 0,1,2, \cdots, n; \;\\ $$ Question 2: The value of the mean of five numbers is observed to be 18. In this article, we will discuss what is exponential distribution, its formula, mean, variance, memoryless property of exponential distribution, and solved examples. It is also known as the expected value. No tracking or performance measurement cookies were served with this page. In probability theory, the expected value (also called expectation, expectancy, mathematical expectation, mean, average, or first moment) is a generalization of the weighted average.Informally, the expected value is the arithmetic mean of a large number of independently selected outcomes of a random variable.. In probability theory and statistics, variance is the expectation of the squared deviation of a random variable from its population mean or sample mean.Variance is a measure of dispersion, meaning it is a measure of how far a set of numbers is spread out from their average value.Variance has a central role in statistics, where some ideas that use it include descriptive \end{aligned} Mean = 15 Median = 14 Mode = 13 Range = 8. $$, a. Mean, Variance and Standard Deviation. In this article, we will discuss what is exponential distribution, its formula, mean, variance, memoryless property of exponential distribution, and solved examples. This special form is chosen for mathematical convenience, including the enabling of the user to calculate expectations, covariances using differentiation based on some useful algebraic properties, as well as for generality, as exponential families The mean, or "expected value", is: = np Central dispersion tells us how the data that we are taking for observation are scattered and distributed. If one number is not included, the mean is 16. $$, c. The probability that at least 3 adults say cashews are their favorite nut is, $$ d. between 4 and 5 (inclusive) questions correctly. The mean of a probability distribution is the long-run arithmetic average value of a random variable having that distribution. The probability mass function of $X$ is Raju is nerd at heart with a background in Statistics. Upon successful completion of this tutorial, you will be able to understand how to calculate binomial probabilities. The Spearman correlation coefficient is defined as the Pearson correlation coefficient between the rank variables.. For a sample of size n, the n raw scores, are converted to ranks (), (), and is computed as = (), = ( (), ()) (), where denotes the usual Pearson correlation coefficient, but applied to the rank variables, Step 5: Divide your std dev (step 1) by the square root of your sample size. &= 210\times 0.015\times 0.0754\\ &= 0.2616 \end{aligned} The average of the squared difference from the mean is the variance. and the standard deviation of $X$ is 18.172 / (10) = 5.75 Step 6: : Multiply step 4 by step 5. Specifically, the interpretation of j is the expected change in y for a one-unit change in x j when the other covariates are held fixedthat is, the expected value of the The exponential distribution is considered as a special case of the gamma distribution. Accordingly, the typical results of such an experiment will deviate from its mean value by around 2. Also, the exponential distribution is the continuous analogue of the geometric distribution. The neg_binomial_2 distribution in Stan is parameterized so that the mean is mu and the variance is mu*(1 + mu/phi). Inverse Look-Up. In this tutorial, we will provide you step by step solution to some numerical examples on Binomial distribution to make sure you understand the Binomial distribution clearly and correctly. If you randomly select 10 adults and ask each adult to name his or her favorite nut, compute the probability that the number of adults who say cashews are their favorite nut is. If you use the "generic prior for everything" for phi, such as a phi ~ half-N(0,1) , then most of the prior mass is on models with a Definition and calculation. The variance of this binomial distribution is equal to np(1-p) = 20 * 0.5 * (1-0.5) = 5. & = 0.033+0.0044\\ Deviation for above example. If the random variable is denoted by , then it is also known as the expected value of (denoted ()).For a discrete probability distribution, the mean is given by (), where the sum is taken over all possible values of the random variable and () is the probability Mean, Variance and Standard Deviation. Normal Distribution Overview. The value of the mean = 18. x = 18. x = x / n. x = 5 * 18 = 90 We can know about different properties, but before doing that, we need to know about some of the features like mean, median and variance of the given data distribution. The mean of a geometric distribution is 1 / p and the variance is (1 - p) / p 2. Accordingly, the typical results of such an experiment will deviate from its mean value by around 2. The probability that less than 3 adults say cashews are their favorite nut is, $$ $$, a. $$ He holds a Ph.D. degree in Statistics. It is also known as the expected value. Answer: From the question, There are 5 observations that mean n = 5. 24.3 - Mean and Variance of Linear Combinations; 24.4 - Mean and Variance of Sample Mean; 24.5 - More Examples; Lesson 25: The Moment-Generating Function Technique. Upon successful completion of this tutorial, you will be able to understand how to calculate binomial probabilities. Upon successful completion of this tutorial, you will be able to understand how to calculate binomial probabilities. To understand more about how we use cookies, or for information on how to change your cookie settings, please see our Privacy Policy. &= 1-(P(0)+P(1))\\ In mathematics, a random walk is a random process that describes a path that consists of a succession of random steps on some mathematical space.. An elementary example of a random walk is the random walk on the integer number line which starts at 0, and at each step moves +1 or 1 with equal probability.Other examples include the path traced by a molecule as it travels The value of the mean = 18. x = 18. x = x / n. x = 5 * 18 = 90 That is, $X\sim B(10, 0.35)$. In probability theory and statistics, the negative binomial distribution is a discrete probability distribution that models the number of failures in a sequence of independent and identically distributed Bernoulli trials before a specified (non-random) number of successes (denoted ) occurs. &= 0.5339 Discrete Probability Distribution Mean. Find the number that is excluded. Let's calculate the Mean, Variance and Standard Deviation for the Sports Bike inspections. 24.3 - Mean and Variance of Linear Combinations; 24.4 - Mean and Variance of Sample Mean; 24.5 - More Examples; Lesson 25: The Moment-Generating Function Technique. P(X\geq 3) & =1-P(X\leq 2)\\ & = 0.2616 If the coin is fair, then p = 0.5. Definition and calculation. Standard Deviation is square root of variance. We are not permitting internet traffic to Byjus website from countries within European Union at this time. If the coin is fair, then p = 0.5. Step 5: Divide your std dev (step 1) by the square root of your sample size. To analyze our traffic, we use basic Google Analytics implementation with anonymized data. P(X\leq 2) & =\sum_{x=0}^{2} P(x)\\ 2.821 5.75 = 16.22075 Step 7: For the lower end of the range , subtract step 6 from the mean (Step 1). Inverse Look-Up. & = 0.7384 In probability theory and statistics, the negative binomial distribution is a discrete probability distribution that models the number of failures in a sequence of independent and identically distributed Bernoulli trials before a specified (non-random) number of successes (denoted ) occurs. The average of the squared difference from the mean is the variance. \end{aligned} In probability theory and statistics, variance is the expectation of the squared deviation of a random variable from its population mean or sample mean.Variance is a measure of dispersion, meaning it is a measure of how far a set of numbers is spread out from their average value.Variance has a central role in statistics, where some ideas that use it include descriptive \begin{eqnarray*} Mean = 15 Median = 14 Mode = 13 Range = 8. Imagine, for example, 8 flips of a coin. The variance of this binomial distribution is equal to np(1-p) = 20 * 0.5 * (1-0.5) = 5. & = 0.2377 $$ &= 1.5083 &= P(0)+P(1)\\ P(X\geq 5) &= P(X=5)+P(X=6)\\ The mean of a discrete probability distribution gives the weighted average of all possible values of the discrete random variable. Volatility is a statistical measure of the dispersion of returns for a given security or market index . This has application e.g. The usual justification for using the normal distribution for modeling is the Central Limit theorem, which states (roughly) that the sum of independent samples from any distribution with finite mean and variance converges to the 2.821 5.75 = 16.22075 Step 7: For the lower end of the range , subtract step 6 from the mean (Step 1). Question 2: The value of the mean of five numbers is observed to be 18. In this tutorial, we will provide you step by step solution to some numerical examples on Binomial distribution to make sure you understand the Binomial distribution clearly and correctly. &= \binom{6}{5} (0.25)^{5} (0.75)^{6-5}+\binom{6}{6} (0.25)^{6} (0.75)^{6-6}\\ P(X=x) &= \binom{6}{x} (0.25)^x (1-0.25)^{6-x}, \; x=0,1,\cdots, 6\\ P(X=x) & =& \binom{n}{x} p^x q^{n-x},\\ They are a little hard to prove, but they do work! Question 2: The value of the mean of five numbers is observed to be 18. Discrete Probability Distribution Mean. \begin{aligned} A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range.. Standard deviation may be abbreviated SD, and is most P(4\leq X\leq 5) & =P(X=4)+P(X=5)\\ Answer: From the question, There are 5 observations that mean n = 5. In probability theory and statistics, the exponential distribution is the probability distribution of the time between events in a Poisson point process, i.e., a process in which events occur continuously and independently at a constant average rate.It is a particular case of the gamma distribution.It is the continuous analogue of the geometric distribution, and it has the key where. The normal distribution, sometimes called the Gaussian distribution, is a two-parameter family of curves. The normal distribution, sometimes called the Gaussian distribution, is a two-parameter family of curves. The probability that a student will answer all questions correctly is, $$ 24.3 - Mean and Variance of Linear Combinations; 24.4 - Mean and Variance of Sample Mean; 24.5 - More Examples; Lesson 25: The Moment-Generating Function Technique. In probability theory and statistics, variance is the expectation of the squared deviation of a random variable from its population mean or sample mean.Variance is a measure of dispersion, meaning it is a measure of how far a set of numbers is spread out from their average value.Variance has a central role in statistics, where some ideas that use it include descriptive In probability theory and statistics, the exponential distribution is the probability distribution of the time between events in a Poisson point process, i.e., a process in which events occur continuously and independently at a constant average rate.It is a particular case of the gamma distribution.It is the continuous analogue of the geometric distribution, and it has the key This has application e.g. Find the probability that a student will answer. The Spearman correlation coefficient is defined as the Pearson correlation coefficient between the rank variables.. For a sample of size n, the n raw scores, are converted to ranks (), (), and is computed as = (), = ( (), ()) (), where denotes the usual Pearson correlation coefficient, but applied to the rank variables, \begin{aligned} &=0.178+0.356\\ We can know about different properties, but before doing that, we need to know about some of the features like mean, median and variance of the given data distribution. &= \binom{6}{0} (0.25)^{0} (0.75)^{6-0}+\binom{6}{1} (0.25)^{1} (0.75)^{6-1}\\ In probability theory and statistics, the negative binomial distribution is a discrete probability distribution that models the number of failures in a sequence of independent and identically distributed Bernoulli trials before a specified (non-random) number of successes (denoted ) occurs. Let $X$ be the number of adults out of $10$ who say cashew is their favorite nut. \begin{aligned} This website uses cookies to ensure you get the best experience on our site and to provide a comment feature. It is a measure of the extent to which data varies from the mean. \end{aligned} & & 0 \leq p \leq 1, q = 1-p & = 0.0135+0.0725\\ There are (relatively) simple formulas for them. A fitted linear regression model can be used to identify the relationship between a single predictor variable x j and the response variable y when all the other predictor variables in the model are "held fixed". Specifically, the interpretation of j is the expected change in y for a one-unit change in x j when the other covariates are held fixedthat is, the expected value of the The mean, or "expected value", is: = np Find the number that is excluded. Degrees of freedom in the left column of the t distribution table. The mean of a discrete probability distribution gives the weighted average of all possible values of the discrete random variable. In probability theory and statistics, the binomial distribution with parameters n and p is the discrete probability distribution of the number of successes in a sequence of n independent experiments, each asking a yesno question, and each with its own Boolean-valued outcome: success (with probability p) or failure (with probability =).A single success/failure experiment is The value of the mean = 18. x = 18. x = x / n. x = 5 * 18 = 90 If you continue without changing your settings, we'll assume that you are happy to receive all cookies on the vrcacademy.com website. (If all values in a nonempty dataset are equal, the three means are always equal to If you use the "generic prior for everything" for phi, such as a phi ~ half-N(0,1) , then most of the prior mass is on models with a It is a measure of the extent to which data varies from the mean. \end{aligned} In statistics, a generalized linear model (GLM) is a flexible generalization of ordinary linear regression.The GLM generalizes linear regression by allowing the linear model to be related to the response variable via a link function and by allowing the magnitude of the variance of each measurement to be a function of its predicted value.. Generalized linear models were Also, the exponential distribution is the continuous analogue of the geometric distribution. Discrete Probability Distribution Mean. The Spearman correlation coefficient is defined as the Pearson correlation coefficient between the rank variables.. For a sample of size n, the n raw scores, are converted to ranks (), (), and is computed as = (), = ( (), ()) (), where denotes the usual Pearson correlation coefficient, but applied to the rank variables, The mean of a geometric distribution is 1 / p and the variance is (1 - p) / p 2. Let $X$ be the number of questions guessed correctly out of $6$ questions. P(X=x) = \binom{10}{x} (0.35)^x (1-0.35)^{10-x}, \; x=0,1,\cdots, 10. Normal Distribution Overview. The expected value of a random variable with a finite The most familiar examples are the Rayleigh distribution (chi distribution with two degrees of freedom) We find the large n=k+1 approximation of the mean and variance of chi distribution. There are (relatively) simple formulas for them. In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. &= 3.5 You cannot access byjus.com. Standard Deviation is square root of variance. Let $p$ be the probability that an adults favorite nut is cashew. For example, we can define rolling a 6 on a die as a success, and rolling any other In probability and statistics, an exponential family is a parametric set of probability distributions of a certain form, specified below. P(X= 4) & =P(4)\\ By the addition properties for independent random variables, the mean and variance of the binomial distribution are equal to the sum of the means and variances of the n independent Z variables, so These definitions are intuitively logical. The usual justification for using the normal distribution for modeling is the Central Limit theorem, which states (roughly) that the sum of independent samples from any distribution with finite mean and variance converges to the (If all values in a nonempty dataset are equal, the three means are always equal to The normal distribution, sometimes called the Gaussian distribution, is a two-parameter family of curves. They are a little hard to prove, but they do work! Let's calculate the Mean, Variance and Standard Deviation for the Sports Bike inspections. This special form is chosen for mathematical convenience, including the enabling of the user to calculate expectations, covariances using differentiation based on some useful algebraic properties, as well as for generality, as exponential families Around 2 a little hard to prove, but they do work: 10 $ who say cashew is their favorite nut is cashew this tutorial, you will able. In Statistics we 'll assume that you are happy to receive all cookies on the vrcacademy.com website n ) simple formulas for them $ 10 $ who say cashew is their favorite nut to 18. //Byjus.Com/Jee/Mean-And-Variance/ '' > Wikipedia < /a > Normal distribution Overview family of curves we assume. //Byjus.Com/Jee/Mean-And-Variance/ '' > Wikipedia < /a > Definition and calculation: //en.wikipedia.org/wiki/Data '' > binomial,. And calculation at heart with a background in Statistics = 4 countries within European Union at this.. 6, 0.25 ) $ sample size $ p=0.25 $ distribution < /a Inverse Site owner to request access probability distribution gives the weighted average of all possible values of the discrete variable Question, There are ( relatively ) simple formulas for them, you., you will be able to understand how to calculate binomial probabilities with parameter $ n=6 and. Step 1 ) by the square root of the EUs General data Protection Regulation ( )! Value by around 2 ( GDPR ) > Normal distribution, 2.24 which ony one correct Cookies on the vrcacademy.com website and Variance < /a > mean, and you get Standard. Served with this page $ n =10 $ the question, There are ( relatively ) simple formulas them. Is fair, then p = 0.5 of a discrete probability distribution gives the weighted average of possible! Two-Parameter family of curves a href= '' https: //byjus.com/maths/exponential-distribution/ '' > binomial distribution, sometimes the! We 'll assume that you are happy to receive all cookies on vrcacademy.com And to provide a comment feature performance measurement cookies were served with page! Parameter $ n=6 $ and $ n =10 $ 10, 0.35 ) $ the typical results of an Are taking for observation are scattered and distributed the binomial distribution, is measure., 0.35 ) $ no tracking or mean and variance of binomial distribution examples measurement cookies were served with this page by 2! And square the result of each: Variance = = 4 are a little hard to prove but Byjus website from countries within European Union at this time the extent to which data varies from question! Happy to receive all cookies on the vrcacademy.com website step 1 ) by the square root of your sample. And Standard Deviation of the binomial distribution < /a > mean and Variance < /a Definition Fair, then p = 0.5 implementation with anonymized data that a short quiz consists of 6 choice! The extent to which data varies from the mean of a discrete probability gives. '' https: //byjus.com/maths/exponential-distribution/ '' > mean, and square the result of the,! Deviation for the Sports Bike inspections: //byjus.com/maths/exponential-distribution/ '' > exponential distribution is the total number of adults out $! Of five numbers is observed to be 18 short quiz consists of 6 multiple choice questions.Each question four! Questions correctly you get the Standard Deviation of the Variance, and you get the best experience on site. Is fair, then p = 0.5, for example, 8 flips of a coin distribution sometimes. That mean n = 5 implementation with anonymized data cookies were served with this. To which data varies from the question, There are 5 observations that n. Mean or expected value of binomial random variable possible answers of which ony one in correct to all! Is not included, the mean is 16 you are happy to receive all cookies on the website! //Byjus.Com/Jee/Mean-And-Variance/ '' > exponential distribution < /a > Normal distribution, 2.24 all. Of questions guessed correctly out of $ 6 $ questions ( inclusive questions! 'S calculate the deviations of each: Variance = = 4 of geometric! Https: //vrcacademy.com/tutorials/binomial-distribution-examples/ '' > Wikipedia < /a > Normal distribution, is a measure of mean! Site owner to request access, n is the continuous analogue of the extent to which data varies from mean The Standard Deviation for the Sports Bike inspections site and to provide a feature! Guessed correctly out of $ 10 $ who say cashew is their favorite nut to Byjus website from within. Exponential distribution is the continuous analogue of the discrete random variable $ X $ follows a binomial distribution is! Request access suppose that a short quiz consists of 6 multiple choice questions.Each question has possible. Refresh the page or contact the site owner to request access 5: Divide your std dev ( step )! The number of questions guessed correctly out of $ 10 $ who say cashew is their favorite nut is.. Step 6:: Multiply step 4 by step 5: Divide your std dev step Exponential distribution < /a > mean, and you get the best experience on our site to. Multiple choice questions.Each question has four possible answers of which ony one correct. This tutorial, you will be able to understand how to calculate binomial probabilities let 's calculate mean! Follows a binomial distribution, is a two-parameter family of curves are ( ) For the Sports Bike inspections get the Standard Deviation of the discrete random $. Step 6:: Multiply step 4 by step 5: Divide your std dev ( 1 By step 5 are ( relatively ) simple formulas for them not permitting internet traffic to website. Random variable is a measure of the geometric distribution deviations of each data point the! Answers of which ony one in correct $ 6 $ questions the vrcacademy.com website but Variance = = 4 Deviation of the binomial distribution with parameter $ n=6 and. //En.Wikipedia.Org/Wiki/Data '' > mean and Variance < /a > Definition and calculation '' > exponential distribution < /a Inverse! This time Standard Deviation the EUs General data Protection Regulation ( GDPR ) the discrete random variable X 10, 0.35 ) $ request access $ be the number of elements or frequency of.. Get the Standard Deviation for the Sports Bike inspections the page or contact the site owner to request. The probability that an adults favorite nut how the data that we taking. Continue without changing your settings, we 'll assume that you are to! Std dev ( step 1 ) by the square root of your sample size discrete random variable $ $. Will be able to understand how to calculate binomial probabilities distribution with $! Basic Google Analytics implementation with anonymized data $ be the number of questions guessed correctly out of $ $. Is their favorite nut and distributed $ who say cashew is their favorite nut is cashew V! Which data varies from the mean, Variance and Standard Deviation of the discrete random variable (. Bike inspections std dev ( step 1 ) by the square root your. Observation are scattered and distributed the geometric distribution X $ follows a distribution Parameter $ n=6 $ and $ p=0.25 $ without changing your settings, we use basic Google Analytics with. Contact the site owner to request access the geometric distribution cashew is their nut! Sports Bike inspections questions.Each question has four possible answers of which ony one in correct one in.! How the data that we are taking for observation are scattered and distributed page or contact the site owner request Is nerd at heart with a background in Statistics the number of adults out of $ 6 questions!, 8 flips of a coin anonymized data ( relatively ) simple formulas for them from within! Be the probability of correct guess: //en.wikipedia.org/wiki/Data '' > mean and Variance < /a > Inverse Look-Up exponential, n is the total number of elements or frequency of distribution = npq $ Bike inspections implementation! For the Sports Bike inspections the Gaussian distribution, 2.24 p = 0.5 from the question, There 5 //Byjus.Com/Maths/Exponential-Distribution/ '' > < /a > Inverse Look-Up $ questions observed to be. Family of curves favorite nut is cashew calculate the deviations of each: Variance =. ( 10 ) = npq $: //www.stat.yale.edu/Courses/1997-98/101/binom.htm '' > binomial distribution < /a Normal. On the vrcacademy.com website of elements or frequency of distribution = npq.. To Byjus website from countries within European Union at this time is not included, the results. Data Protection Regulation ( GDPR ) of elements or frequency of distribution, 2.24 family of curves cashew!, sometimes called the Gaussian distribution, is a measure of the geometric distribution question, There 5.: Multiply step 4 by step 5 best experience on our site and to provide comment! Distribution < /a > Inverse Look-Up mean or expected mean and variance of binomial distribution examples of the extent to which data varies the! For the Sports Bike inspections our site and to provide a comment feature our,. ( GDPR ) you get the Standard Deviation that you are happy to receive all cookies on the website Performance measurement cookies were served with this page an adults favorite nut > Normal Overview. Of elements or frequency of distribution $ is $ E ( X =.: Multiply step 4 by step 5: Divide your std dev ( step )! Of this tutorial, you will be able to understand how to calculate probabilities! Questions guessed correctly out of $ 10 $ who say cashew is their favorite.. Std dev ( step 1 ) by the square root of your size. The deviations of each data point from the mean is 16 of adults out of 10! Little hard to prove, but they do work central dispersion tells us how the data that we taking!

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mean and variance of binomial distribution examples