normal curve


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Related to normal curve: standard deviation

normal curve

a frequency distribution which has a bell-shaped symmetrical pattern where it is possible to calculate the height of the curve (the frequency) corresponding to any given numerical value.

Normal curves are used in statistical QUALITY CONTROL to establish the limits of variation in the size or other characteristic of a product which is to be regarded as acceptable in SAMPLES of a product being tested. For example, if a component is intended to measure an average of 100 mm across and the standard deviation is 2 mm, then the testers would expect 95% of a sample of components to measure between 96 mm and 104 mm across, and 99% of the sample to measure between 94 mm and 106 mm across. If the latter range of sizes was felt be acceptable in terms of the technical performance of the product, then this confidence interval would lead to the whole batch of components being rejected if more than 1% of sample components were larger or smaller than these broad limits. By contrast, if a tougher criterion was imposed and only components measuring 96 mm to 104 mm across were to be regarded as technically acceptable, then 95% of sample components would be acceptable. and if more than 5% of the sample were larger or smaller than these size limits then the whole batch of components would be rejected.

References in periodicals archive ?
Now assume that C [intersection] H is contained in a rational normal curve [T.
g] and [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] (i = 1,2) are geodesic torsion of normal curve and normal curvature of parameter curves, respectively.
When combined with the concept of normal curve and the knowledge of particular CBC parameters, such as RDW and red cell indices, histograms become a practical working tool in the initial stage of morphological analysis.
Students are identified as having intellectual disabilities, for example, if their tested IQs place them on the lower reaches of the normal curve (i.
It is worth noting here that there is another type of standard score, McCall's T scores, which are modified Z scores adjusted to fit the normal curve (Guilford and Fruchter, 1978).
I envision the integration enterprise offering insights from two-millennia of Christian spiritual formation as legitimate ways of helping certain clients "Flourish," to use Seligman's (2011) word, on the positive side of the normal curve and in the wonderfully abnormal Kingdom of God.
Total of 52 patients had normal curve of Spee, 33 patients had deep curve of Spee, 15 patients had flat curve of Spee as shown in Table-2.
For a standard normal curve, the value of p is 2 as z value, estimated for each speed observation, considers mean ([mu]) and standard deviation ([sigma]) for defining the distribution.
Regression analysis was used to determine if the decision to end intervention could be used to predict (a) student performance-level categories [below basic, basic, proficient, advanced] and (b) student reading achievement on Normal Curve Equivalency (NCE) scores in 3rd, 4th, and 5th grades.
He covers dimensions and units, analysis methodology, mechanics, electrical circuits, thermodynamics, fluid mechanics, data analysis statistics and graphing, mathematical formulas in algebraic geometry, trigonometry, calculus, unit conversions, physical properties of materials, and the standard normal curve.
Mastoid pneumatization and normal curve distribution.
In each generation there is a normal curve of distribution for intelligence and where the cut-off point for grades occurs is a political decision.