  The {\delta} Sct stars are a diverse group of intermediate-mass pulsating
stars located on and near the main sequence within the classical instability
strip in the Hertzsprung-Russell diagram. Many of these stars are hybrid stars
pulsating simultaneously with pressure and gravity modes that probe the physics
at different depths within a star's interior. Using two large ensembles of
{\delta} Sct stars observed by the Kepler Space Telescope, the instrumental
biases inherent to Kepler mission data and the statistical properties of these
stars are investigated. An important focus of this work is an analysis of the
relationships between the pulsational and stellar parameters, and their
distribution within the classical instability strip. It is found that a
non-negligible fraction of main sequence {\delta} Sct stars exist outside
theoretical predictions of the classical instability boundaries, which
indicates the necessity of a mass-dependent mixing length parameter to
simultaneously explain low- and high-radial order pressure modes in {\delta}
Sct stars within the Hertzsprung-Russell diagram. Furthermore, a search for
regularities in the amplitude spectra of these stars is also presented,
specifically the frequency difference between pressure modes of consecutive
radial order. In this work, it is demonstrated that an ensemble-based approach
using space photometry from the Kepler mission is not only plausible for
{\delta} Sct stars, but that it is a valuable method for identifying the most
promising stars for mode identification and asteroseismic modelling. The full
scientific potential of studying {\delta} Sct stars is as yet unrealised. The
ensembles discussed in this paper represent a high-quality data set for future
studies of rotation and angular momentum transport inside A and F stars using
asteroseismology.
