PN B05577AC
C-8
Optical Models
Statistics
When a distribution is perfectly symmetrical, the values of mean, median, and mode coincide.
Under these circumstances, the coefficient of skewness equals zero (g1 = 0).
For right-skewed distributions, the mainly larger values increase the value of the mean, while the
value of the mode is unaffected and the skewness coefficient is positive (g1 > 0).
For left-skewed distributions, the mainly smaller particles reduce the value of the mean, while the
value of the mode is unaffected and the skewness coefficient is negative (g1 < 0).
Kurtosis
Kurtosis, g2, is a measure of the peakedness of a distribution. It is calculated by determining
moments about the mean from the following equation:
The normal, or Gaussian, distribution is the standard against which the peakedness of other curves
is measured. A normal distribution is referred to as mesokurtic (g2 = 0).
If the distribution has a higher, sharper peak than the normal curve, then it has a larger degree of
kurtosis and is termed leptokurtic (g2 > 0). In a leptokurtic distribution most of the particle sizes are
close to the mean size.
Arithmetic
Geometric
Arithmetic
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Содержание LS 13 320
Страница 4: ...PN B05577AC iv Revision History ...
Страница 12: ...PN B05577AC xii Safety Notice Scope of Manual ...
Страница 30: ...PN B05577AC xxx LS 13 320 Introduction System Components ...
Страница 57: ...PN B05577AC 2 21 Installation Making Measurements 2 Figure 2 18 Run Cycle Options Dialog ...
Страница 58: ...PN B05577AC 2 22 Installation Making Measurements Figure 2 19 Reference Background File Selection ...
Страница 59: ...PN B05577AC 3 1 CHAPTER 3 LS 13 320 Software Figure 3 1 LS 13 320 Software ...
Страница 80: ...PN B05577AC 3 22 LS 13 320 Software Preference Options ...
Страница 86: ...PN B05577AC 3 28 LS 13 320 Software Preference Options ...
Страница 105: ...PN B05577AC 3 47 LS 13 320 Software High Security 3 Figure 3 5 User Privileges Dialog High Security ...
Страница 116: ...PN B05577AC 4 10 Regulatory Compliance 21 CFR Part 11 Starting Security Enabled Software ...
Страница 118: ...PN B05577AC 5 2 Data File Menus RunFile Menu 3 Select the file you wish to overlay with the current opened file 4 Open ...
Страница 169: ...PN B05577AC 6 39 Sample Modules Micro Liquid Module 6 Figure 6 27 SOM List Dialog ...
Страница 216: ...PN B05577AC 6 86 Sample Modules Universal Liquid Module ...
Страница 228: ...PN B05577AC B 10 Sample Handling Diluent Selection ...
Страница 238: ...PN B05577AC C 10 Optical Models Statistics ...
Страница 252: ...PN B05577AC Warranty 2 Beckman Coulter Inc Customer End User License Agreement ...
Страница 253: ......