Consistency testing internal tests

This illustrates the general philosophy of taxometrics. For something to be deemed a taxon, it needs to clear several hurdles, which arguably makes taxometrics the most rigorous analytic approach to the study of taxonomy. The last two conditions (e and f) are external consistency tests and apply to all taxometric studies. On the other hand, a, b, c, and d are internal consistency tests. Some of them are specific to MAXCOV—other procedures have their own unique internal consistency tests—but a and b can be performed with any of the CCK methods. We will now consider the first three internal consistency tests (a, b, and c) in detail and postpone discussion of the distribution of taxon membership. 

MAMBAC offers two standard internal consistency tests, the nose count test and the base rate variability test. MAMBAC allows for two analyses per pair of indicators, which means that two indicators produce two plots, three indicators produce six plots, four indicators produce 12 plots, five indicators produce 20 plots, etc. Waller s MAMBAC does not do this automatically, and the investigator has to run each analysis independently. Ruscio s software, on the other hand, is fully automatic. 

Nose count and base rate variability consistency tests are possible with MAXSLOPE, although it is not yet clear how these tests behave when the underlying distributions are of the difficult kind. Luckily, MAXSLOPE puts less emphasis on internal consistency testing and stresses external consistency testing instead. MAXSLOPE is different from other taxometric algorithms and thus can provide a strong test of external consistency for other procedures. 

Although there are weaknesses in the findings, we can conclude that the taxonic conjecture successfully passed several internal and external consistency tests. An important aspect of this is that the CCK findings were replicated with a fundamentally different method (BNMM). However, questions about the nature of the identified taxon remain. To address this, the... 

Cost must be understood in the context of quahty. If quahty means conformance to requirements, then quality costs must be understood in terms of costs of conformance and costs of nonconformance, , as illustrated in Figure 19-1. In industrial terms, costs of conformance are divided into prevention costs and appraisal costs. Costs of nonconformance consist of internal and external failure costs. For a laboratory testing process, calibration is a good example of a cost incurred to prevent problems. Lhcewise, quality control is a cost for appraising performance, a repeat run is an internal failure cost for poor analytical performance, and repeat requests for tests because of poor analytical quality are an external failure cost. 

Qmintitative Internal consistency tests should be applied by experimenters before reporting results of future lattice experiments. 

In this section results will be presented using test samples to determine the accuracy of our approach. Further on an example is shown using the system to analyse casting defects. For the experiments moderate projective magnifications between 1.1 and 1.4 were chosen. The test samples used to determine the accuracy of calibration, 3D defect position and volume estimation consist of several holes representing internal defects of different but known size and shape. 

A significant revision to the SMR scheme was introduced in 1991 in response to consumer desire for greater consistency in natural mbber (13). Other producing countries have similar specification schemes (14), as does the International Standards Organization (ISO) (15). An example of the specifications for TSR is given in Table 1 for the present Standard Malaysian scheme. Except for SMR 5, rheograph and cure test data (delta torque, optimum cure time, and scorch) are provided. 

Mathematical Consistency Requirements. Theoretical equations provide a method by which a data set s internal consistency can be tested or missing data can be derived from known values of related properties. The abiUty of data to fit a proven model may also provide insight into whether that data behaves correctiy and follows expected trends. For example, poor fit of vapor pressure versus temperature data to a generally accepted correlating equation could indicate systematic data error or bias. A simple sermlogarithmic form, (eg, the Antoine equation, eq. 8), has been shown to apply to most organic Hquids, so substantial deviation from this model might indicate a problem. Many other simple thermodynamics relations can provide useful data tests (1—5,18,21). 

Diatomaceous earth A fine, siliceous (made of silica) "earth" composed mainly of the skeletal remains of diatoms (single cell microscopic algae with rigid internal structure consisting mainly of silica). Tests prove that DE leaches unacceptable amounts of silicate into the water for fish health. If used as a filter substance, a silicone removing resin should be employed afterwards. 

Gravitational Methods GONELL AIR ELUTRIATOR. This is the prototype of all analytical separators with laminar air flow. It consists of a cylindrical brass tube (or a series of tubes) with a conical base. An air inlet is provided in this base on the axis of the tube. The sample of powder is placed in the inlet cone, and air is blown thru the largest tube until separation is deemed complete, or for specified periods of time. The residue is removed, weighed, and transferred to a smaller diameter tube, and the test is repeated. The tube should have polished internal surfaces and should be periodically tapped or vibrated to disturb settled powder... 

Consistency, working time, setting time and hardening of an AB cement can be assessed only imperfectly in the laboratory. These properties are important to the clinician but are very difficult to define in terms of laboratory tests. The consistency or workability of a cement paste relates to internal forces of cohesion, represented by the yield stress, rather than to viscosity, since cements behave as plastic bodies and not as Newtonian liquids. The optimum stiffness or consistency required of a cement paste depends upon its application. 

It must be remarked that terminology is not consistent and there are many widely used synon)ms. Quality control in this Chapter refers to practices best described as internal quality control. Quahty assessment is often referred to as external quality control, proficiency testing, interlaboratory comparisons, round robins or other terms. Internal Quality Control and External Quality Assessment are preferred because they best describe the objectives for which the RMs are being used, i.e. the immediate and active control of the results being reported from an analytical run or event, and an objective, retrospective assessment of the quality of those results. 

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