Probability distributions are indispensable instatisticssince they provide a way of knowing how a random variable behaves. They are also very efficient in predicting the probabilities of different possible outcomes that may occur. These notions are not for mathematicians alone but have practical applicatio...
The rank sum and signed-rank tests were both proposed by American statistician Frank Wilcoxon in a groundbreaking research paper published in 1945. The tests laid the foundation forhypothesis testingofnonparametric statistics, which are used for population data that can be ranked but do not have num...
The interquartile range is the difference between the upper quartile and the lower quartile. It is used fairly frequently as a measure of variability, particularly in the Box Plot. It is used less than some alternatives because it is not related to any of the important theoretical distributions....
which can be either a representation of the entire population or a sample of a population. Descriptive statistics are broken down into measures of central tendency and measures of variability (spread). Measures of central tendency include themean,median, andmode, while measures of variability include...
The Gumbel Distribution is a probability distribution of extreme values. In probability theory and statistics, the Gumbel distribution is used to model the distribution of the maximum (or the minimum) of a number of samples of various distributions. About...
In probability theory and statistics, the Gumbel distribution is used to model the distribution of the maximum (or the minimum) of a number of samples of various distributions. About Generalized Extreme Value Distribution In probability theory and statistics, the Generalized Extreme Value (GEV) Distri...
A hypothesis test can have left-, right-, or two-tailed distributions. The test statistic’s value, the critical value, and the confidence intervals are used to conclude. Below are a few significant hypothesis tests that are employed in inferential statistics....
Definition: Suppose we have a high-dimensional set D of data points along with 1) a mapping (or class of mappings) to a lower-dimensional space, and 2) a distribution (or class of distributions) P on the lower-dimensional space. If most of D is consistent with the distribution P , bu...
In the purely temporal setting, Shmueli and Fienberg [10] discuss a number of options. Dillard and Shmueli have applied wavelets to multiple time series [11]. Naus and Wartenberg =-=[12]-=- have developed purely temporal scan statistics for two data types, but their purpose is different...
Kurtosis describes the “fatness” of the tails found in probability distributions. There are three kurtosis categories: mesokurtic (normal), platykurtic (less than normal), and leptokurtic (more than normal). Kurtosis risk is a measurement of how often an investment’s price moves dramatically. ...