# Ch13Def - 1. It’s completely described by giving the mean...

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STAT 110 – Chapter 13 Definitions Strategy for Exploring Data: 1. Always plot your data: make a graph, usually a histogram or stemplot. 2. Look for the overall pattern (shape, center, spread) and for striking deviations such as outliers. 3. Choose either the five-number summary or the mean and standard deviation to briefly describe center and spread in numbers. An additional step: 4. Sometimes the overall pattern of a large number of observations is so regular that we can describe it by a smooth curve. density curve – a curve that has no negative values where the area under the curve is exactly one normal curves – symmetric, bell-shaped curves with these properties:

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Unformatted text preview: 1. It’s completely described by giving the mean and standard deviation. 2. The mean determines the center of the distribution. 3. The standard deviation determines the location of the “inflection points” 68 – 95 – 99.7 standard score – the number of standard deviations above or below the mean at which an observation is located (also known as z-score.) c th percentile – a value such that c percent of the observations lies below it and the rest lie above it observation = mean + (standard score)(standard deviation) deviation standard mean-n observatio score standard = s x-x z = (z)(s) x x + =...
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## This note was uploaded on 02/10/2011 for the course STAT 110 taught by Professor Johnson during the Spring '07 term at South Carolina.

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Ch13Def - 1. It’s completely described by giving the mean...

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