Cochran's Q Test - Description

Description

Cochran's Q test is

H0: The treatments are equally effective.
Ha: There is a difference in effectiveness among treatments.

The Cochran's Q test statistic is

T = k\left(k-1\right)\frac{\sum\limits_{j=1}^k \left(X_{\bullet j} - \frac{N}{k}\right)^2}{\sum\limits_{i=1}^b X_{i\bullet}\left(k-X_{i\bullet}\right)}

where

k is the number of treatments
X• j is the column total for the jth treatment
b is the number of blocks
Xi • is the row total for the ith block
N is the grand total

Read more about this topic:  Cochran's Q Test

Famous quotes containing the word description:

    “As they are not seen on their way down the streams, it is thought by fishermen that they never return, but waste away and die, clinging to rocks and stumps of trees for an indefinite period; a tragic feature in the scenery of the river bottoms worthy to be remembered with Shakespeare’s description of the sea-floor.”
    —Henry David Thoreau (1817–1862)

    “The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St. Paul’s, like the editions of Balbec and Palmyra.”
    —Horace Walpole (1717–1797)

    “To give an accurate description of what has never occurred is not merely the proper occupation of the historian, but the inalienable privilege of any man of parts and culture.”
    —Oscar Wilde (1854–1900)