"by two observations" is a grammatically correct and usable phrase in written English.
It is typically used to indicate that something has been determined or established through the observation of two separate events or instances. Here is an example: "By two observations, it was clear that the bird preferred to build its nest in trees rather than on the ground."
Our work is motivated by two observations.
Our analysis of employment rates is motivated by two observations.
Resource flexibility was the distinct value as considered by two observations.
This research is motivated by two observations: Firstly, the conventional approach for solving such problems serially, as implemented, e.g., in zggev (LAPACK), is to treat complex symmetric problems as general complex and therefore does not exploit the structural properties.
This is evidenced by two observations: (1) P3HT exhibits a good contact with PCBM in molecular level and (2) the P3HT-PCBM system forms a well-organized molecular network in each of the electron donor and accepter phases.
Motivated by two observations: (1) independent component analysis (ICA) is capable of encoding intrinsic features underlying video data; and (2) videos of different actions can be easily distinguished by their intrinsic features, we propose a simple but effective action recognition framework based on the recently proposed overcomplete ICA model.
The alignment's accuracy was verified by two observations on these motifs: 1), the most variability is shown in the turret region, which functionally is strongly implicated in susceptibility to toxin binding; and 2), the selectivity filter and pore helix are the most highly conserved regions.
This hypothesis is supported by two observations: (1) species in which the display arena has become smaller produce less intense skrraa calls and (2) the species with the most intense courtship displays, the spotted bowerbird, is unique in building an avenue bower with see-through walls that protect the female while she is watching and listening to the courting male (Berglund et al. 1996).
This difference could be explained by two observations: firstly, patients assuming analgesic mixtures are historically older, when the clinical practice for treatment of chronic headache was based on the use of classic mixtures, as association of caffeine, phenothiazines or barbiturates and NSAIDs.
