normal school: see teacher training.

Normal, town (1990 pop. 40,023), McLean co., central Ill.; inc. 1865. It is the center of a productive farming region. Motor vehicles are manufactured in Normal. The town originally grew around Illinois State Univ. (1857; formerly called Illinois State Normal Univ.), which remains a major contributor to its economy.

Guarantee of same trading opportunities (i.e., tariff concessions) already granted to the most favoured nation (MFN). It is a method of establishing equal trading opportunities among states by making originally bilateral agreements multilateral. Attempts to guarantee equal trading opportunities were incorporated into commercial treaties as far back as the early 17th century. The Anglo-French treaty signed in 1860 became the model for many later trade agreements, establishing a set of interlocking tariff concessions (see tariff) later extended worldwide by most-favoured-nation treatment. MFN treatment has always applied primarily to the duties charged on imports, but specific provisions have extended the principle to other areas of economic contact, including property rights, patents, and copyrights. Seealso General Agreement on Tariffs and Trade; reciprocity; World Trade Organization.

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In statistics, a frequency distribution in the shape of the classic bell curve. It accurately represents most variations in such attributes as height and weight. Any random variable with a normal distribution has a mean (see mean, median, and mode) and a standard deviation that indicates how much the data as a whole deviate from the mean. The standard deviation is smaller for data clustered closely around the mean value and larger for more dispersed data sets.

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