Use function definitions in StatsAPI (#744)

Author: rafaqz

Project.toml

@@ -22,7 +22,7 @@ DataStructures = "0.10, 0.11, 0.12, 0.13, 0.14, 0.17, 0.18"
 LogExpFunctions = "0.3"
 Missings = "0.3, 0.4, 1.0"
 SortingAlgorithms = "0.3, 1.0"
-StatsAPI = "1"
+StatsAPI = "1.2"
 julia = "1"
 
 [extras]

docs/Project.toml

@@ -1,6 +1,7 @@
 [deps]
 Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
+StatsAPI = "82ae8749-77ed-4fe6-ae5f-f523153014b0"
 
 [compat]
 Documenter = "0.24"

docs/make.jl

@@ -1,4 +1,4 @@
-using Documenter, StatsBase, Statistics, Random, LinearAlgebra
+using Documenter, StatsBase, StatsAPI, Statistics, Random, LinearAlgebra
 
 # Workaround for JuliaLang/julia/pull/28625
 if Base.HOME_PROJECT[] !== nothing
@@ -7,7 +7,7 @@ end
 
 makedocs(
     sitename = "StatsBase.jl",
-    modules = [StatsBase],
+    modules = [StatsBase, StatsAPI],
     pages = ["index.md",
              "weights.md",
              "scalarstats.md",
@@ -29,4 +29,4 @@ makedocs(
 
 deploydocs(
     repo = "github.com/JuliaStats/StatsBase.jl.git"
-)
+)

docs/src/statmodels.md

@@ -1,6 +1,7 @@
 # Abstraction for Statistical Models
 
-This package defines an abstract type `StatisticalModel`, and an abstract subtype `RegressionModel`.
+[StatsAPI.jl](https://github.com/JuliaStats/StatsAPI.jl) defines an abstract type `StatisticalModel`,
+and an abstract subtype `RegressionModel`. They are both extended by StatsBase, and documented here.
 
 Particularly, instances of `StatisticalModel` implement the following methods.
 
@@ -30,7 +31,7 @@ rss
 score
 stderror
 vcov
-weights(::StatisticalModel)
+weights
 ```
 
 `RegressionModel` extends `StatisticalModel` by implementing the following additional methods.
@@ -52,4 +53,4 @@ residuals
 An exception type is provided to signal convergence failures during model estimation:
 ```@docs
 ConvergenceException
-```
+```

docs/src/weights.md

@@ -149,5 +149,5 @@ fweights
 pweights
 eweights
 uweights
-weights
+weights(vs::AbstractArray{<:Real})
 ```

src/StatsBase.jl

@@ -20,7 +20,15 @@ import LinearAlgebra: BlasReal, BlasFloat
 import Statistics: mean, mean!, var, varm, varm!, std, stdm, cov, covm,
                    cor, corm, cov2cor!, unscaled_covzm, quantile, sqrt!,
                    median, middle
-import StatsAPI: pairwise, pairwise!
+using StatsAPI: StatisticalModel, RegressionModel
+import StatsAPI: pairwise, pairwise!, params, params!,
+                 fitted, response, responsename, meanresponse, modelmatrix,
+                 crossmodelmatrix, leverage, cooksdistance, residuals, predict,
+                 predict!, dof_residual, coef, coefnames, coeftable, confint,
+                 deviance, islinear, nulldeviance, loglikelihood, nullloglikelihood,
+                 loglikelihood, loglikelihood, score, nobs, dof, mss, rss,
+                 informationmatrix, stderror, vcov, weights, isfitted, fit, fit!,
+                 aic, aicc, bic, r2, r², adjr2
 
     ## tackle compatibility issues