"variation in the distribution" is a perfectly correct and usable phrase in written English.
For example, you could use the phrase in the sentence, "Economists have noticed a variation in the distribution of wealth over the past decade."
Sample 2: a high resolution micro XRF map revealed significant variation in the distribution of Cu both within and outside the ink area.
Variation in the distribution of initial synaptic strengths predicts a form of metaplasticity and can account for differences in learning rules observed under several physiological and genetic manipulations.
Ge cautions marketers that they may see "some variation in the distribution of their ads" as the changes to ad targeting roll out, but that in the long run they will benefit from reaching the right people.
Extreme genetic heterogeneity along with remarkable variation in the distribution of causative variants across in different ethnicities makes single gene testing inefficient for hearing loss.
This analysis highlights two previously unknown regional trends, including variation in the distribution of multicomponent sites and potential short-term depopulation of a significant part of the region.
Given the seasonal variation in the distribution of rainfall, significant differences can exist between the annual maximum and seasonal maximum T-yr return period discharges.
Chi-square analysis of the data showed a significant (P <.01) variation in the distribution of ovulation times between mares treated with Chorulon and mares treated with Ovuplant.
A significant variation in the distribution of three TEs, MAGGY, MGL, and Pot2 was observed among the fingerprint contigs of the physical map.
Moreover, variation in the extent of EER decline among individuals is associated with variation in the distribution of perikymata along their enamel surfaces.
Larger variation in the distribution of interfacial bond strengths was found to result in a decrease in the overall strength for PCD grades.
Another contributing factor was increased protection conferred against Hi AOM by protein D. Geographical variation in the distribution of otopathogens was a third factor explaining differences between trials.
