Discrete factors

A discrete factor is a factor that can take on only a limited number of values... 

Figure 2.9 Response surface showing an inherently continuous response (percent purity of a protein) as a function of an inherently discrete factor (number of recrystallizations).

The discrete factor number of recrystallizations is naturally ordered (see Figure 2.9). It obviously makes sense to plot yield against the number of recrystallizations in the order 1, 2, 3, 4, 5, 6, 7, 8, 9 it would not make sense to plot the yield against a different ordering of the number of recrystallizations, say 3, 7, 5, 8, 2, 1, 4, 9, 6. Other discrete factors are not always as meaningfully ordered, especially if they are... 

The discrete factor solvent number is recognized as a simple bookkeeping designation. We can replace it with the continuous factor dipole moment expressed on a ratio scale and obtain, finally, the response surface shown in Figure 2.13. A special note of caution is in order. Even when data such as that shown in Figure 2.13 is obtained, the suspected property might not be responsible for the observed effect it may well be that a different, correlated property is the true cause (see Section 1.2 on masquerading factors). 

The voltage from an autotransformer has both a lower bound (0 V a.c.) and an upper bound (usually about 130 V a.c.) and is an example of a naturally constrained discrete factor. The upper constraint could be changed if the autotransformer were... 

Examples of the use of discrete factors for various applications are found in Table 9-22, assuming that the present time is when the first funds are expended. 

A discrete factor is a factor that can take on only a limited number of values within a given domain. A discrete response is a response that can take on only a... 

The discrete factor solvent number is recognized as a simple bookkeeping designation. We can replace it with the continuous factor dipole moment and obtain, finally, the response surface shown in Figure 2.13. 

Another division of the factors can be made into mixture-related, quantitative (continuous), or qualitative (discrete) factors (4,5,16,18,24). A mixture-related factor in CE is usually related to a mixture of solvents, for example, the composition of the background electrolyte solution. A quantitative factor can vary on a continuous scale, for example, the buffer pH, the electrolyte concentration, the additive concentration, the capillary temperature, or the voltage. A qualitative factor, on the other hand, varies on a discrete nominal scale, for example, batch or manufacturer of a reagent, solvent, or capillary. 

State that we cannot know all factors and processes that influence the values we observe for a certain wetland biogeochemical property. Simple statistical methods as a continuous response (regression analysis) or as a set of responses to discrete factors (analysis of variance, ANOVA) have been used extensively in wetland research, in order to relate elements in biogeochemical processes or determine the extent to which a particular factor may influence a process. 

Discrete or continuous factor discrete factor continuous factor continuous factor... 

Table 10.2 Continuous and discrete factors that are likely to affect reactions.

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