(This parameter is explained in § Pseudocount below.) Additive smoothing is a type of shrinkage estimator, as the resulting estimate will be between the empirical probability (relative frequency) x i N {\textstyle \scriptstyle {\frac {x_{i}}{N}}} , and the uniform probability 1 d {\textstyle \scriptstyle {\frac {1}{d}}} . Invoking Laplace's rule of succession, some authors have argued[citation needed] that α should be 1 (in which case the term add-one smoothing[2][3] is also used)[further explanation needed], though in practice a smaller value is typically chosen.