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Multiple correspondence analysis

To investigate relationships between crustacean grazing rates on Phaeocystis and experimental conditions, a multiple correspondence analysis (MCA) followed by a hierarchical cluster analysis (HCA) was performed using SPAD 3.5 software (Lebart et al. 1988). The combination of MCA and cluster analysis is a common way to explore relationships among a large number of variables and to facilitate interpretation of the correspondence analysis results (Lebart et al. 2000). MCA uses a contingency table as data, which provides a simultaneous representation of the observations (rows) and variables (column) in a factorial space. This form of multivariate analysis describes the total inertia (or variability) of a multidimensional... [Pg.157]

Table 5 Active structural variables used in the multiple correspondence analysis (MCA), n denotes the number of observations from each source... Table 5 Active structural variables used in the multiple correspondence analysis (MCA), n denotes the number of observations from each source...
Table 6 Sources of data used for the multiple correspondence analysis (MCA) and hierarchical cluster analysis (HCA) presented in Fig. 1, and quantitative summary in Fig. 2, respectively... Table 6 Sources of data used for the multiple correspondence analysis (MCA) and hierarchical cluster analysis (HCA) presented in Fig. 1, and quantitative summary in Fig. 2, respectively...
Broadly speaking, the statistical strategies of analysis can be classified into two families of methods, namely (i) factor analytical methods including, in particular, multidimensional scaling (MDS) and multiple correspondence analysis (MCA) and (ii) methods pertaining to cluster analysis and additive trees. As is usually the case, the choice of one method over another depends on several factors (i) the domain of application (i.e. traditionally, some methods are more popular than others in each particular domain of application) (ii) the individual preferences and background of each practitioner and (iii) the availability of appropriate (and user-friendly) software. [Pg.160]

Beyond the information based on the factors, the information provided by the subjects on the groups appears to be essential to interpret the factorial plane. This information is represented as categories are represented in Multiple Correspondence Analysis (MCA, Husson et al, 2010). In other words, as shown in Fig. 9.8, smoothies and description of the groups provided by subjects are represented on the same factorial plane, which is an important and very convenient feature. [Pg.210]

The relationships between the variables and their categories in ESAW can be identified using Multiple Correspondence Analysis (MCA hereinafter). MCA analysis, as an exploratory technique, provides an intuitive representation of how certain categories are close enough to intuit an association (Conte et al., 2011). MCA is also a useful method for presentation purposes because the plots are very intuitive (Perez-Alonso et al., 2012). [Pg.80]

Correlation of Secondary Nucleation Rate. The nucleation rate equation (2) was correlated by using multiple regression analysis at 70 C. Only data corresponding to the accelerating phase of nucleation rate was used in the correlation. The rate equation obtained at 70 C is... [Pg.339]

Using the E values evaluated from pore size distribution curves (Equation 1) corresponding to different degrees of conversion and the conversion-time data, the values of effective diffusivities of CO2 in the core and shell sections (D and D a respectively) are determined from Equations 8 and 9by a multiple regression analysis as 0.08 cmz/s and 0.12 cmz/s respectively at 860 °C. [Pg.522]

In addition to Ro and MF, inert matters of coal such as ash and sulfur, which do not soften and melt, are important properties of coal to be evaluated. The relations between FOB prices of coals from various parts of the world and the above-mentioned factors were analyzed by multiple regression analysis.(3) This permits economic evaluation of coals as raw materials for coke-making. Petroleum residual oils and petroleum coke can similarly be evaluated as raw materials. The most difficult problem here is how to evaluate factors corresponding to Ro and MF in coals.(6) This report presents primarily an estimation of such factors for evaluation. [Pg.264]

By way of illustration take a case where there are ten observations and corresponding activity values Ai to Ai0 and eight variables Vi to Vq are considered. Multiple regression analysis yields equation (l) where r2 = O.85, F, r = 19 8 (p < 0.005) and... [Pg.134]

Inadequate results are sometimes obtained with a single independent variable. This shows that one independent variable does not provide enough information to predict the corresponding value of the dependent variable. We can approach this problem, if we use additional independent variables and develop a multiple regression analysis to achieve a meaningful relationship. Here, we can employ a linear regression model in cases where the dependent variable is affected by two or more controlled variables. [Pg.12]

Functionality An integrator tool must manage links between objects of interdependent documents. In general, links may be m n relationships, i.e., a link connects m source objects with n target objects. They may be used for multiple purposes browsing, correspondence analysis, and transformation. [Pg.227]

Besides the scaled (continuous) descriptors, dichotomous indicators of either the presence or absence of molecular features have often been used in QSAR analyses. Indicator variables are assigned values of 1 or 0 corresponding to yes or no if certain substructures, substituents, substitution patterns occur (e.g. di-ortho substitution, isomerism, etc.). Their use in multiple regression analysis yields the group contribution, given by the respective regression coefficient, to the total activity. [Pg.41]

As an illustration, let us mention that the use of additive trees for analyzing free sorting data is relatively popular in psychology (Dubois, 1991), whereas in psychoacoustics, MDS methods are more often used (Gygi et al., 2007 MacAdams et al., 1995). In the field of sensory analysis that particularly interests us here, the mainstream is to use MDS methods (Faye et al., 2004 King et al., 1998 Lawless et al., 1995 Parr et al, 2007). However, alternative methods of analysis, such as multiple correspondences and allied methods, have also been proposed in this framework (Cadoret et al, 2009 Qannari et al., 2009 Takane, 1981,1982). [Pg.160]

Pt, CuS, and Ag2S electrodes were used in the workofKaneki and coworkers [86] investigating the applicability of potentiometric measurements for detecting pork freshness. The outputs of these electrodes have been analyzed by principal component analysis (PCA) and multiple regression analysis (MRA) in order to find the correlation with the results of viable bacterial counts. By using the potentiometric sensors, the pork freshness was evaluated and the PCA and MRA corresponded to the degree of bacterial increases more simply and rapidly than other methods. [Pg.200]

ABSTRACT Analysis of accident reports has been a useful tool in occupational safety research. Important variables related to main circumstances of accidents are being gathered in Europe according to European Statistics on Accidents at Work framework (ESAW). This paper present a method for the identification of possible public safety programs based on the application of Multiple Correspondence Analyses (MCA) and the introduction of the concepts of task and accident mechanism. The method is presented using the accidents notified in the manufacturing sector of Andalusia. This method can help policy makers in the identification of areas of public intervention. [Pg.79]

A stepwise multiple regression analysis (SPSS-X) was run on the data, entering successively age, gender, socioeconomic class, and whole tooth lead. In the table below we present the equation coefficients with their corresponding T-value and its significance. The (variance) explained after each step in the analysis is shown on the right hand side. [Pg.252]


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See also in sourсe #XX -- [ Pg.160 , Pg.166 , Pg.192 , Pg.210 ]

See also in sourсe #XX -- [ Pg.160 , Pg.166 , Pg.192 , Pg.210 ]




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Correspondence analysis

Multiple analyses

Multiplicity analysis

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