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.

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References in periodicals archive ?

We have [h.sup.1](H, I[Z.sub.C[intersection]H,H](3)) = d - 13 if and only if C [intersection] H is contained in a rational normal curve of H.

Curves of low positive genus and low degree on a general heptic hypersurface of [P.sup.5]

where [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] and 1/[R.sub.g] (i = 1,2) are geodesic curvatures of the parameter curves and the normal curve, respectively.

The differential geometry of regular curves on a regular time-like surface

Majority showed normal curve with left shift and mild broad base curve.

Study of RBC histogram in various anemias

This provides additional information about risk because you can see what extreme values might be possible or, by using normal curve probabilities, determine the probability of a value occurring within an interval or above or below a specific value.

Using excel to perform Monte Carlo simulations

Regularities of this distribution allow determining the frequency of most empirical series, although the curve of the last variation deviates from the normal curve. The bulk of the analyzed cells are characterized by normal diploid chromosomes for cattle--79.80%, yak--78.60%, horses 74,56% and sheep--75.89%.

The character of diploid variation chromosome set of animal species Bos Taurus, Bos Grinniens, Ovis Aries and Equus Caballus

Students in special education--that is, students with exceptionalities--are operationally defined with reference to their position on the normal curve. Students are identified as having intellectual disabilities, for example, if their tested IQs place them on the lower reaches of the normal curve (i.e., at least 2 SDs below the norm).

Diversity in teacher education and special education: the issues that divide

As stated above, T scores are adjusted to fit the normal curve, so the distribution of T scores is not skewed.

The leading group effect: illusionary declines in scholastic standard scores of mid-range Japanese junior high school pupils

The Five Integrative Topics: A View from the Past Normal Curves. At the time of my first exposure, psychology was a discipline that focused only on the left--side the "painful" or "deficient" side--of the normal curve.

Integration in three tenses: a journey from separate and not equal to integral and interwoven

Every null normal curve lying fully in [E.sup.4.sub.1] is a second kind null osculating curve.

Some characterizations of null osculating curves in the Minkowski space-time/Nullkooldumiskoverate iseloomustusest Minkowski aegruumis

You'd find the normal curve and there right at the top end, spiking on its own, would be the Fiat Panda.

Panda gets even better; The Fiat Panda is perhaps the archetypal inexpensive but stylish car. ANDY ENRIGHT takes a look at the latest model

Our result showed that 52 patients had a normal curve of Spee, 33 had a deep curve and 15 had a flat curve of Spee.

Influence of malocclusion on the depth of curve of Spee

For all vehicle types, except motorized 2-wheelers, the histogram assumed a normal curve. Therefore, for these categories, normal distribution was selected to represent the field values.

Study on heterogeneous traffic flow characteristics of a two-lane road/Heterogeninio transporto eismo srauto charakteristikos dvieju juostu kelyje