Search results
Results from the WOW.Com Content Network
Algorithms for calculating variance play a major role in computational statistics.A key difficulty in the design of good algorithms for this problem is that formulas for the variance may involve sums of squares, which can lead to numerical instability as well as to arithmetic overflow when dealing with large values.
For a set of numbers {10, 15, 30, 45, 57, 52 63, 72, 81, 93, 102, 105}, if this set is the whole data population for some measurement, then variance is the population variance 932.743 as the sum of the squared deviations about the mean of this set, divided by 12 as the number of the set members.
There are two divisions, Elementary and Middle School. Elementary level problems are for grades 4-6 and Middle School level problems are for grades 7-8, though 4-6 graders may participate in Middle School problems. Hundreds of thousands of students participate annually in MOEMS events. MOEMS plans soon to develop an online teacher training program.
The material on the test ranges from Algebra I and II, trigonometry, analytic geometry, and pre-calculus with problems adjusted for the middle school level. [1] Calculator Applications or Calculator is an 80-question exam that students are given only 30 minutes to solve. This test requires the use of a calculator, knowledge of a few crucial ...
A measure of statistical dispersion is a nonnegative real number that is zero if all the data are the same and increases as the data become more diverse. Most measures of dispersion have the same units as the quantity being measured. In other words, if the measurements are in metres or seconds, so is the measure of dispersion.
Bootstrapping can be interpreted in a Bayesian framework using a scheme that creates new data sets through reweighting the initial data. Given a set of data points, the weighting assigned to data point in a new data set is =, where is a low-to-high ordered list of uniformly distributed random numbers on [,], preceded by 0 and succeeded by 1.
Analysis of variance (ANOVA) is a family of statistical methods used to compare the means of two or more groups by analyzing variance. Specifically, ANOVA compares the amount of variation between the group means to the amount of variation within each group.
Firstly, while the sample variance (using Bessel's correction) is an unbiased estimator of the population variance, its square root, the sample standard deviation, is a biased estimate of the population standard deviation; because the square root is a concave function, the bias is downward, by Jensen's inequality.