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  2. Nullity (graph theory) - Wikipedia

    en.wikipedia.org/wiki/Nullity_(graph_theory)

    The nullity of a graph in the mathematical subject of graph theory can mean either of two unrelated numbers. If the graph has n vertices and m edges, then: In the matrix theory of graphs, the nullity of the graph is the nullity of the adjacency matrix A of the graph. The nullity of A is given by n − r where r is the rank of the adjacency

  3. Multiple comparisons problem - Wikipedia

    en.wikipedia.org/wiki/Multiple_comparisons_problem

    The first row shows the possible p-values as a function of the number of blue and red dots in the sample. Although the 30 samples were all simulated under the null, one of the resulting p-values is small enough to produce a false rejection at the typical level 0.05 in the absence of correction.

  4. Surrogate data testing - Wikipedia

    en.wikipedia.org/wiki/Surrogate_data_testing

    The last surrogate data methods do not depend on a particular model, nor on any parameters, thus they are non-parametric methods. These surrogate data methods are usually based on preserving the linear structure of the original series (for instance, by preserving the autocorrelation function, or equivalently the periodogram, an estimate of the ...

  5. Row and column spaces - Wikipedia

    en.wikipedia.org/wiki/Row_and_column_spaces

    The nullity of a matrix is the dimension of the null space, and is equal to the number of columns in the reduced row echelon form that do not have pivots. [7] The rank and nullity of a matrix A with n columns are related by the equation: ⁡ + ⁡ =.

  6. Null distribution - Wikipedia

    en.wikipedia.org/wiki/Null_distribution

    Null distribution is a tool scientists often use when conducting experiments. The null distribution is the distribution of two sets of data under a null hypothesis. If the results of the two sets of data are not outside the parameters of the expected results, then the null hypothesis is said to be true. Null and alternative distribution

  7. James A. D. W. Anderson - Wikipedia

    en.wikipedia.org/wiki/James_A._D._W._Anderson

    This is due to nullity being a number, whereas NaN is an indeterminate value. It is easy to see that nullity is not an indeterminate value. For example, the numerator of nullity is zero, but the numerator of an indeterminate value is indeterminate. Thus nullity and indeterminant have different properties, which is to say they are not the same!

  8. Cochran–Mantel–Haenszel statistics - Wikipedia

    en.wikipedia.org/wiki/Cochran–Mantel–Haenszel...

    In statistics, the Cochran–Mantel–Haenszel test (CMH) is a test used in the analysis of stratified or matched categorical data.It allows an investigator to test the association between a binary predictor or treatment and a binary outcome such as case or control status while taking into account the stratification. [1]

  9. Null model - Wikipedia

    en.wikipedia.org/wiki/Null_model

    One null model of utility in the study of complex networks is that proposed by Newman and Girvan, consisting of a randomized version of an original graph , produced through edges being rewired at random, under the constraint that the expected degree of each vertex matches the degree of the vertex in the original graph. [1]