Further Contribution to the Square Transformation of the Error Component of the Multiplicative Time Series Model
- Umah Alfred Chikadibia; Onyemachi Chris Uchechi; Chikezie David Chidi
- DOI: 10.5281/zenodo.21354951
- ISA Journal of Engineering and Technology (ISAJET)
Conditions initially designed
to yield successful transformation in time series modeling are considered. For
these cases, this article proposes an approach aimed at exploring the range at
which the expectation of the untransformed attains equilibrium with the
transformed and maintains variance as a proportional product of the
untransformed. Methodologically, new results are obtained, and relations in
comparison of normality are compared. The square transformation has a moderate
effect on distribution shape. The square
transformed could be used to
reduce left skewness as squaring makes sense even if the variable concerned is
zero or positive, given that and are identical. It is the motive of this
paper to primarily investigate the limits of the square transformation with a
view to eliminating distributional assumptions that may impede expectations for
the confidence intervals. We compared means and variances of both the transformed
and untransformed to establish the bounding curves.
Keywords: Transformation, Statistical properties, distributional
assumptions, confidence intervals.