$${\boldsymbol{\upbeta}}_1=\mathbf{log}\left(\frac{\mathbf{Af}{\mathbf{f}}_1}{\mathbf{Af}{\mathbf{f}}_{\mathbf{R}}}\right)+\mathbf{log}\left(\frac{{\mathbf{t}}_{1\mathbf{N}}}{{\mathbf{t}}_{1\mathbf{N}}+{\mathbf{t}}_{2\mathbf{N}}}\right)$$ No special interest
$${\boldsymbol{\upbeta}}_2=\mathbf{log}\left(\frac{\mathbf{Af}{\mathbf{f}}_2}{\mathbf{Af}{\mathbf{f}}_1}\right)+\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{N}}}{{\mathbf{t}}_{1\mathbf{N}}}\right)$$ No special interest
$${\boldsymbol{\upbeta}}_3=\mathbf{log}\left(\frac{{\mathbf{t}}_{1\mathbf{T}}+{\mathbf{t}}_{2\mathbf{T}}}{{\mathbf{t}}_{1\mathbf{N}}+{\mathbf{t}}_{2\mathbf{N}}}\right)$$ Logarithm of the overall fold change of the event. Differential expression present if different from zero.
$${\boldsymbol{\upbeta}}_4=\mathbf{log}\left(\frac{{\mathbf{t}}_{1\mathbf{T}}}{{\mathbf{t}}_{1\mathbf{T}}+{\mathbf{t}}_{2\mathbf{T}}}\right)-\mathbf{log}\left(\frac{{\mathbf{t}}_{1\mathbf{N}}}{{\mathbf{t}}_{1\mathbf{N}}+{\mathbf{t}}_{2\mathbf{N}}}\right)$$ Difference of the logarithms of the fold change using relative concentrations of isoform 1 in both conditions. AS present if different from 0.
$${\boldsymbol{\upbeta}}_5=\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{T}}}{{\mathbf{t}}_{1\mathbf{T}}}\right)-\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{N}}}{{\mathbf{t}}_{1\mathbf{N}}}\right)$$ Difference of the logarithms of the fold change of both isoforms. AS present if different from zero.
$${\boldsymbol{\upbeta}}_4+{\boldsymbol{\upbeta}}_5=\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{T}}}{{\mathbf{t}}_{1\mathbf{T}}+{\mathbf{t}}_{2\mathbf{T}}}\right)-\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{N}}}{{\mathbf{t}}_{1\mathbf{N}}+{\mathbf{t}}_{2\mathbf{N}}}\right)$$ Difference of the logarithms of the fold change using relative concentrations of isoform 2 in both conditions. AS present if different from 0.
$${\boldsymbol{\upbeta}}_3+{\boldsymbol{\upbeta}}_4 = \mathbf{log}\left(\frac{{\mathbf{t}}_{1\mathbf{T}}}{{\mathbf{t}}_{1\mathbf{N}}}\right)$$ Logarithm of the fold change of isoform 1.
$${\boldsymbol{\upbeta}}_3+{\boldsymbol{\upbeta}}_4+{\boldsymbol{\upbeta}}_5=\mathbf{log}\left(\frac{{\mathbf{t}}_{2\mathbf{T}}}{{\mathbf{t}}_{2\mathbf{N}}}\right)$$ Logarithm of the fold change of isoform 2.