Mean - Wikipedia
...The arithmetic mean of a set of numbers x1, x2, ..., x n is typically denoted using an overhead bar, . [note 1] If the numbers are from observing a sample of a larger group, the arithmetic mean is termed the sample mean ( ) to distinguish it from the group mean (or expected value) of the underlying distribution, denoted or . [note 2][3]...
https://en.m.wikipedia.org/wiki/Mean
Normal Distribution - GeeksforGeeks
...The distribution is defined by its mean (?) - the peak of the curve and standard deviation (?) - which controls the spread of the curve. The Normal Distribution Curve (also called the Bell Curve or Gaussian Curve) is the graphical representation of this distribution, showing: Symmetry around the mean (?)....
https://www.geeksforgeeks.org/maths/normal-distribution/
Chapter Post-assessment A. Direction: Select the letter that corresponds
...The best answer is: c. It becomes more normal as the sample size increases, according to the Central Limit Theorem. Explanation: The Central Limit Theorem states that the distribution of sample means approaches a normal distribution as the sample size becomes large, regardless of the population's distribution....
https://askfilo.com/user-question-answers-smart-solutions/chapter-post-assessment-a-direction-select-the-letter-that-3435343938333533
Covariance - Wikipedia
...A distinction must be made between (1) the covariance of two random variables, which is a population parameter that can be seen as a property of the joint probability distribution, and (2) the sample covariance, which in addition to serving as a descriptor of the sample, also serves as an estimated value of the population parameter....
https://en.m.wikipedia.org/wiki/Covariance
Skewness - Wikipedia
...For example, a zero value in skewness means that the tails on both sides of the mean balance out overall; this is the case for a symmetric distribution but can also be true for an asymmetric distribution where one tail is long and thin, and the other is short but fat....
https://en.m.wikipedia.org/wiki/Skewness
Z-Score: Definition, Formula and Calculation - Statistics How To
...Z-score definition. How to calculate it (includes step by step video). Hundreds of statistics help articles, videos....
https://www.statisticshowto.com/probability-and-statistics/z-score/
Mean squared error - Wikipedia
...If the estimator is derived as a sample statistic and is used to estimate some population parameter, then the expectation is with respect to the sampling distribution of the sample statistic....
https://en.m.wikipedia.org/wiki/Mean_squared_error
Variance - GeeksforGeeks
...While calculating the sample mean, we make sure to calculate the sample mean, i.e., the mean of the sample data set, not the population mean. We can define the sample variance as the mean of the squares of the differences between the sample data points and the sample mean....
https://www.geeksforgeeks.org/maths/variance/
t-statistic - Wikipedia
...It is very similar to the z-score but with the difference that t -statistic is used when the sample size is small or the population standard deviation is unknown. For example, the t -statistic is used in estimating the population mean from a sampling distribution of sample means if the population standard deviation is unknown....
https://en.m.wikipedia.org/wiki/T-statistic
Chi-squared distribution - Wikipedia
...The sample mean of i.i.d. chi-squared variables of degree is distributed according to a gamma distribution with shape and scale parameters: Asymptotically, given that for a shape parameter going to infinity, a Gamma distribution converges towards a normal distribution with expectation and variance , the sample mean converges towards: Note that we would have obtained the same result invoking ......
https://en.m.wikipedia.org/wiki/Chi-squared_distribution