Table 1

Geometrical parameters of the hook curve
Hook parameter
 symbol
 typical range
 characteristics
Start point
 Σ(0) ≈ Σstart,
 1.0 – 2.5
 Non-specific signal

Δ(0) ≈ Δstart
 0.0 – 0.15
 PM/MM-gain (N)
End point
 Σ(∞),
 3.5 – 4.8
 Saturation signal

Δ(∞)
 0
 PM/MM-gain (as)
Width
 β = Σ(∞)-Σ(0)
 2.2 – 3.2
 Measuring range, non- specific binding strength in logarithmic scale
asymptotic height
 α
 0.75 – 1.1
 PM/MM-gain (S)
decay constant
 λ
 0.5 – 1.5
 Decay rate of the density distribution of the Σ-values; this S/N-index characterizes the mean ratio of specific and non- specific binding (S/N- ratio) in the logarithmic scale.
Expression index
 φ = (β - MathΔ(0)) - λ ≈ β - λ
 1.5 – 2.5
 Mean specific signal in logarithmic scale

Binder et al. Algorithms for Molecular Biology 2008 3:11   doi:10.1186/1748-7188-3-11