ASTM D4375-96

NOTICE: This standard has either been superseded and replaced by a new version or
withdrawn. Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4375 – 96
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Practice for
1
Basic Statistics in Committee D-19 on Water
This standard is issued under the fixed designation D 4375; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope variables need to be calculated. The technique for calculating
these variables and presenting these results is developed in this
1.1 This practice establishes a uniform standard for
practice.
calculating, expressing, and symbolizing some basic statistical
parameters.
5. Significance and Use
2. Referenced Documents
5.1 This practice assures the user that all calculations are
2.1 ASTM Standards:
performed in the same manner and that all results are presented
2
D 1129 Terminology Relating to Water
consistently.
3
E 456 Terminology Relating to Quality and Statistics
6. Calculation of Statistical Parameters
3. Terminology
6.1 Mean:
3.1 Definitions:
3.1.1 population—the set of data that consists of all possible n
x¯ 5 x /n
observations or values of a certain phenomenon. (
i
i 5 1
3.1.2 sample—a set of data from the population.
N
3.1.3 statistic—an estimated quantity for a parameter
μ 5 X /N
( i
i 5 1
calculated from a sample.
3.1.4 parameter—a measurable quantity characteristic of a
6.2 Variance:
population.
n
2 2
3.1.5 observation—a fact duly noted and recorded.
s 5 ~x 2 x¯! /n21
(
i
i 5 1
3.1.6 sample or population size—(N may be finite or
N
infinite, but N and n are finite for all calculations).
2 2
s
5 ~X 2 μ! /N
( i
3.1.7 For definitions of related statistical terms, see
i 5 1
Terminology E 456.
6.3 Standard Deviation:
3.1.8 For definitions of other terms used in this practice,
2
refer to Terminology D 1129.
s 5 =s
3.2 Symbols for Sample and P
...