6,990 research outputs found
Two-Sample Tests for High Dimensional Means with Thresholding and Data Transformation
We consider testing for two-sample means of high dimensional populations by
thresholding. Two tests are investigated, which are designed for better power
performance when the two population mean vectors differ only in sparsely
populated coordinates. The first test is constructed by carrying out
thresholding to remove the non-signal bearing dimensions. The second test
combines data transformation via the precision matrix with the thresholding.
The benefits of the thresholding and the data transformations are showed by a
reduced variance of the test thresholding statistics, the improved power and a
wider detection region of the tests. Simulation experiments and an empirical
study are performed to confirm the theoretical findings and to demonstrate the
practical implementations.Comment: 64 page
Probing CP-violating coupling in
We investigate the possibility of probing the CP-violating
coupling in the process at the future high
luminosity colliders. Our numerical results show that the cross
section for this process can be significantly increased for the allowed CP
phase and center of mass energy. For example the cross section is about 6
times of that in the standard model (SM) for and
(see text for definition). The simulation for the signal
process and its
backgrounds shows that the signal significance can reach more than
and for
respectively, with the integrated luminosity and
. For , the signal
significance can be greater than 5 for and 3.9 for
with the CP phase . Besides
the cross section enhancement, the CP-violating coupling will
induce the forward-backward asymmetry which is absent in the SM and is
a clear signal of new CP violation. Compared with the in the Higgs
decay , the can be greatly enhanced in
the production process. For example can reach 0.5 for and . Due to the large backgrounds, the
significance of the expected can only be observed at with
and . It is
essential to trigger the single photon in the final state to separate the
bottom jets arising from scalar or vector bosons, in order to isolate the
signal from the backgrounds more efficiently.Comment: Published version. 19 pages, 11 figures, 3 tables. Discussion on the
forward-backward asymmetry is adde
- …