Figure 5. Experimental and theoretical cumulative probability distribution functions (CDF) P(C) of dimensionless odorant concentration C/<C> (concentration divided by the total mean concentration).

(A) Experimental CDF (solid) as measured at 75 m from a propylene (passive tracer) source and its best exponential fit (dashed) plotted on a logarithmic scale (taken from [19]). The intermittency is included in the plots in the non-zero value of P(C) for zero concentrations (see Methods). The experimental data clearly follow the exponential CDF, except close to C = 0, which is caused by technical issues in the measurement process [19]. The relatively high value of measured intermittency (close to 47%) is caused mainly by initial data processing [19]. (B) CDF predicted by the pheromone reception model together with its best exponential fit, the scales correspond to panel (A) After correcting (see Methods) for the fact that the intermittency predicted by the pheromone reception model (20%) is lower than that measured in [19] (as explained in the Discussion), the predictions correspond well to the measured data in (A), except at very high values of L _air where they are less frequent than expected. Since this deviation is apparent only for events occurring with probability P<0.01, it can be considered as non-significant.