Editing Sensitivity analysis (section)

=== Visual analysis ===
[[File:Scatter plots for sensitivity analysis bis.jpg|thumb|right | upright=2 | Figure 2. Sampling-based sensitivity analysis by scatterplots. ''Y'' (vertical axis) is a function of four factors. The points in the four scatterplots are always the same though sorted differently, i.e. by ''Z''<sub>1</sub>, ''Z''<sub>2</sub>, ''Z''<sub>3</sub>, ''Z''<sub>4</sub> in turn. Note that the abscissa is different for each plot: (−5,&nbsp;+5) for ''Z''<sub>1</sub>, (−8,&nbsp;+8) for ''Z''<sub>2</sub>, (−10,&nbsp;+10) for ''Z''<sub>3</sub> and ''Z''<sub>4</sub>. ''Z''<sub>4</sub> is most important in influencing ''Y'' as it imparts more 'shape' on ''Y''.]]

The first intuitive approach (especially useful in less complex cases) is to analyze the relationship between each input <math>Z_i</math> and the output <math>Y</math> using scatter plots, and observe the behavior of these pairs. The diagrams give an initial idea of the correlation and which input has an impact on the output. Figure 2 shows an example where two inputs, <math>Z_3</math> and <math>Z_4</math> are highly correlated with the output.