A statistic describes a sample, while a parameter describes an entire population. A sample is a smaller subset that is representative of a larger population.
Know MoreThe symbols differ when reporting statistics versus parameters. The average symbol for a statistic is an x with a line on top of it. For a parameter, the average is represented by the symbol μ. Since it is not always possible to collect every single observation in a population, sampling procedures are used to select a representative sample. Random sampling allows a statistician to calculate statistics about a sample and apply them to a population.
Learn more about StatisticsThe formula to find a sample variance is as follows: s squared equals sigma(x-x-bar)squared over n-1. Working out the problem involves determining the mean, subtracting the mean for each number and then squaring the result and then determining the average of the squared differences.
Full Answer >A t-test is designed to test a null hypothesis by determining if two sets of data are significantly different from one another, while a chi-squared test tests the null hypothesis by finding out if there is a relationship between the two sets of data. The null hypothesis is a prediction that states there is no relationship between two variables.
Full Answer >The term sensitivity in epidemiology is a statistical measure on individuals who are positive, and they test positive in the tests. On the other hand, specificity refers to a statistical measure of individuals who tests negative and are truly negative.
Full Answer >In mathematics, a ratio illustrates the relationship between two things, often quantities, while a proportion refers to the equality of two given ratios. A ratio is generally only an expression, while a proportion can be written as an algebraic equation.
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