Update for 1.6+ requirement

src/influence.jl

@@ -4,23 +4,10 @@
 
 StatsBase.leverage(model::LinPredModel) = _leverage(model, model.pp)
 
-# TODO: Delete this once the minimum required Julia version is set to something recent
-if VERSION >= v"1.3.0-DEV.94"
- const _diagm = diagm
-else
- function _diagm(n::Integer, m::Integer, v::AbstractVector)
- length(v) == min(n, m) || throw(DimensionMismatch())
- D = similar(v, (n, m))
- fill!(D, zero(eltype(D)))
- copyto!(view(D, diagind(D)), v)
- return D
- end
-end
-
 function _leverage(_, pred::DensePredQR)
  Q = pred.qr.Q
  r = linpred_rank(pred)
- y = _diagm(size(Q, 1), r, trues(r))
+ y = diagm(size(Q, 1), r, trues(r))
  Z = Q * y
  return vec(sum(abs2, Z; dims=1))
 end
@@ -37,7 +24,7 @@ function _leverage(model, pred::DensePredChol{<:Any,<:CholeskyPivoted})
  if any(x -> isapprox(x, zero(x)), diag(C.L))
  Q = qr!(X).Q
  r = rank(C)
- y = _diagm(size(Q, 1), r, trues(r))
+ y = diagm(size(Q, 1), r, trues(r))
  X = Q * y
  else
  choldiv!(C, X)