# Degrees Of Freedom

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Degrees Of Freedom

In statistics, the number of values in a study that are free to vary. For example, if you have to take ten different courses to graduate, and only ten different courses are offered, then you have nine degrees of freedom. Nine semesters you will be able to choose which class to take; the tenth semester, there will only be one class left to take - there is no choice, if you want to graduate.

Degrees of freedom are commonly discussed in relation to chi-square and other forms of hypothesis testing statistics. It is important to calculate the degree(s) of freedom when determining the significance of a chi square statistic and the validity of the null hypothesis.

There are two types of chi square tests: the goodness-of-fit test (does a coin tossed 100 times turn up heads 50 times and tails 50 times?) and the test of independence (is there a relationship between gender and a perfect SAT score?).

Degrees of freedom are used to then determine whether a particular null hypothesis can be rejected based on the number of variables and samples of in the experiment. For example, while a sample size of 50 students might not be large enough to obtain significant information, obtaining the same results from a study of 500 samples can be judged as being valid.

Investment dictionary. . 2012.

### Look at other dictionaries:

• Degrees of freedom — can mean: Degrees of freedom (mechanics), independent displacements and/or rotations that specify the orientation of the body or system Degrees of freedom (physics and chemistry), a term used in explaining dependence on parameters, or the… …   Wikipedia

• degrees of freedom — n. Statistics the number of independent variables entering into a statistical measure or frequency distribution * * * …   Universalium

• degrees of freedom — n. Statistics the number of independent variables entering into a statistical measure or frequency distribution …   English World dictionary

• degrees of freedom — laisvės laipsnių skaičius statusas T sritis chemija apibrėžtis Skaičius parametrų, kuriuos galima keisti tam tikrose ribose, kai fazių skaičius nesikeičia. atitikmenys: angl. degrees of freedom; number of degrees of freedom; system variance;… …   Chemijos terminų aiškinamasis žodynas

• degrees of freedom — the number of ways the members of a sample can vary independently; a numerical index of a family of probability distributions that corresponds to the number of independent variables in the definition of each member, e.g., the chi squared… …   Medical dictionary

• degrees of freedom — number of unrestricted values that can be applied in any order to a distribution (Statistics) …   English contemporary dictionary

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• Degrees of freedom (mechanics) — In mechanics, degrees of freedom (DOF) are the set of independent displacements and/or rotations that specify completely the displaced or deformed position and orientation of the body or system. This is a fundamental concept relating to systems… …   Wikipedia

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