Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. The sample...

Random-sampling mechanism Resampling (statistics) Pseudo-random number sampling Sample size determination Sampling (case studies) Sampling bias Sampling distribution...

Since the sample error can often be estimated beforehand as a function of the sample size, various methods of sample size determination are used to...

the sampling mean distribution obtained is equal to the variance of the population divided by the sample size. This is because as the sample size increases...

{\displaystyle c_{\rm {v}}\,} itself. For many practical purposes (such as sample size determination and calculation of confidence intervals) it is s l n {\displaystyle...

a sample is taken without knowing, in advance, how many observations will be acceptable according to some criterion. In such cases, the sample size N...

statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that...

subgroups' sample sizes proportional to the amount of data available from the subgroups, rather than scaling sample sizes to subgroup sizes (or to their...

given sample size. The sampling distribution depends on the underlying distribution of the population, the statistic being considered, the sampling procedure...

number of interviews and costs given the desired accuracy. For a fixed sample size, the expected random error is smaller when most of the variation in the...

the mean square error (MSE) of the regression. The denominator is the sample size reduced by the number of model parameters estimated from the same data...

probability mass function g(x) the range of the Xi is the range of a sample of size n from a population with distribution function G(x). We can assume without...

x ¯ {\displaystyle {\bar {x}}} is the sample mean, s is the sample standard deviation and n is the sample size. The degrees of freedom used in this test...

a computer, sampling from it to form a new sample (called a 'resample' or bootstrap sample) that is also of size N. The bootstrap sample is taken from...

n {\displaystyle n} is the sample size: Sample median ∼ N ( μ = m , σ 2 = 1 4 n f ( m ) 2 ) {\displaystyle {\text{Sample median}}\sim {\mathcal {N}}\left(\mu...

square root of the sample size, and is estimated by using the sample standard deviation divided by the square root of the sample size. For example, a poll's...

population. Sampling Simple random sampling Stratified sampling Stratification(clinical trials) Quota sampling Sample size determination Sampling error Nickolas...

(intervals) are adjacent and are typically (but not required to be) of equal size. Histograms give a rough sense of the density of the underlying distribution...

univariate sample of quantitative data. It can also refer to the population parameter that is estimated by the MAD calculated from a sample. For a univariate...

chance of selection). The ratio of the size of this statistical sample to the size of the population is called a sampling fraction. It is then possible to estimate...

variability, and sample size), and the effect size of interest. High statistical power is related to low variability, large sample sizes, large effects...

is the distribution function associated with the empirical measure of a sample. This cumulative distribution function is a step function that jumps up...

hypothesis test used in the analysis of contingency tables when the sample sizes are large. In simpler terms, this test is primarily used to examine whether...

expected value of the raw sample moment is equal to the k-th raw moment of the population, if that moment exists, for any sample size n. It is thus an unbiased...

Cross-validation, sometimes called rotation estimation or out-of-sample testing, is any of various similar model validation techniques for assessing how...

that four numbers are observed or recorded, resulting in a sample of size 4. If the sample values are 6, 9, 3, 7, the order statistics would be denoted...

{y}})^{2}}}}}} where n {\displaystyle n} is sample size x i , y i {\displaystyle x_{i},y_{i}} are the individual sample points indexed with i x ¯ = 1 n ∑ i =...

{\displaystyle V_{N}} . One could take a random sample of fifty villagers, but quite possibly such a random sample would not include anybody with the disease...

distributed population). Like most statistical significance tests, if the sample size is sufficiently large this test may detect even trivial departures from...

population size and E is the expectation operator. Assuming that the variance is not infinite and that the central limit theorem applies to the sample then...