Statistics negative correlation

Each oil-dispersant combination shows a unique threshold or onset of dispersion [589]. A statistic analysis showed that the principal factors involved are the oil composition, dispersant formulation, sea surface turbulence, and dispersant quantity [588]. The composition of the oil is very important. The effectiveness of the dispersant formulation correlates strongly with the amount of the saturate components in the oil. The other components of the oil (i.e., asphaltenes, resins, or polar substances and aromatic fractions) show a negative correlation with the dispersant effectiveness. The viscosity of the oil is determined by the composition of the oil. Therefore viscosity and composition are responsible for the effectiveness of a dispersant. The dispersant composition is significant and interacts with the oil composition. Sea turbulence strongly affects dispersant effectiveness. The effectiveness rises with increasing turbulence to a maximal value. The effectiveness for commercial dispersants is a Gaussian distribution around a certain salinity value. 

MINITAB readily produces many useful manipulations of data such as were obtained in this experiment. Figure 2 shows histograms of the responses, indicating that, for the limited number of data points, the experimental values for each response approach a normal distribution. Thus, the statistical analysis was considered valid. Table III shows a copy of the computer printout of a correlation table with all the responses. Clearly, Property A and Property B are negatively correlated, as predicted, but Property B and Property E are not well correlated. 

Statistical analysis of enzyme amounts could be used to demonstrate which enzyme plays an important role in the decolourization process of azo dyes, and it was reported that the complete decolourization time and enzyme activity are negatively correlative [47]. 

Not all studies of soy protein diets in humans have found significant reduction of plasma cholesterol. In addition to differences in diet formulations and soy protein preparations, one reason that has been proposed for these disparities is that there is a statistically significant negative correlation between the initial cholesterol level and the decrease of cholesterol achieved with the soy protein diet (r -0.48, p < 0.01) (23). In other words, those with normal or slightly elevated cholesterol levels would be expected to show less change in cholesterol as a result of the soy diet than individuals with markedly elevated lipids. Sirtori and associates (23) have followed a number of type II hyperlipoproteinemic patients who have been maintained on the soy... 

Higher iron levels with increased MCV are seen in heavy drinkers [33], (E. Cruz, impublished results). It is known that a small proportion of heavy drinkers develop liver disease. In a study of control subjects and heavy drinkers genotyped for HFE (Cruz et al, unpublished results), we have confirmed and added to this observation. In heavy drinkers with a particular HFE genotype, there is a statistically significant negative correlation between CD8-I- T cell numbers and some liver enzyme (i.e. ALT) levels. 

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