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                 "bin/ecs"
@@ -4128,7 +4272,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "5.2-dev"
+                    "dev-master": "5.3-dev"
                 }
             },
             "autoload": {
@@ -4145,20 +4289,20 @@
                 "MIT"
             ],
             "description": "Use Coding Standard with 0-knowledge of PHP-CS-Fixer and PHP_CodeSniffer.",
-            "time": "2018-11-03T10:43:05+00:00"
+            "time": "2018-12-07T13:16:16+00:00"
         },
         {
             "name": "symplify/package-builder",
-            "version": "v5.2.0",
+            "version": "v5.2.15",
             "source": {
                 "type": "git",
                 "url": "https://github.com/Symplify/PackageBuilder.git",
-                "reference": "0b88fb5038d015e00179286d55445695372245aa"
+                "reference": "978e9ac03eb4640282be4b56677e0dd8e665893d"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/Symplify/PackageBuilder/zipball/0b88fb5038d015e00179286d55445695372245aa",
-                "reference": "0b88fb5038d015e00179286d55445695372245aa",
+                "url": "https://api.github.com/repos/Symplify/PackageBuilder/zipball/978e9ac03eb4640282be4b56677e0dd8e665893d",
+                "reference": "978e9ac03eb4640282be4b56677e0dd8e665893d",
                 "shasum": ""
             },
             "require": {
@@ -4180,7 +4324,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "5.2-dev"
+                    "dev-master": "5.3-dev"
                 }
             },
             "autoload": {
@@ -4193,20 +4337,20 @@
                 "MIT"
             ],
             "description": "Dependency Injection, Console and Kernel toolkit for Symplify packages.",
-            "time": "2018-11-03T13:34:54+00:00"
+            "time": "2018-12-02T21:24:21+00:00"
         },
         {
             "name": "symplify/token-runner",
-            "version": "v5.2.0",
+            "version": "v5.2.15",
             "source": {
                 "type": "git",
                 "url": "https://github.com/Symplify/TokenRunner.git",
-                "reference": "88747d0c1b8021106d62fe1c8bc15284224d48a7"
+                "reference": "73878adbf28a7ce974f896af4f3890a295c97d17"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/Symplify/TokenRunner/zipball/88747d0c1b8021106d62fe1c8bc15284224d48a7",
-                "reference": "88747d0c1b8021106d62fe1c8bc15284224d48a7",
+                "url": "https://api.github.com/repos/Symplify/TokenRunner/zipball/73878adbf28a7ce974f896af4f3890a295c97d17",
+                "reference": "73878adbf28a7ce974f896af4f3890a295c97d17",
                 "shasum": ""
             },
             "require": {
@@ -4215,8 +4359,8 @@
                 "nette/utils": "^2.5",
                 "php": "^7.1",
                 "squizlabs/php_codesniffer": "^3.3",
-                "symplify/better-phpdoc-parser": "^5.2",
-                "symplify/package-builder": "^5.2",
+                "symplify/better-phpdoc-parser": "^5.2.15",
+                "symplify/package-builder": "^5.2.15",
                 "thecodingmachine/safe": "^0.1.6"
             },
             "require-dev": {
@@ -4225,7 +4369,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "5.2-dev"
+                    "dev-master": "5.3-dev"
                 }
             },
             "autoload": {
@@ -4238,20 +4382,20 @@
                 "MIT"
             ],
             "description": "Set of utils for PHP_CodeSniffer and PHP CS Fixer.",
-            "time": "2018-10-31T09:23:48+00:00"
+            "time": "2018-12-07T13:16:16+00:00"
         },
         {
             "name": "thecodingmachine/safe",
-            "version": "v0.1.6",
+            "version": "v0.1.8",
             "source": {
                 "type": "git",
                 "url": "https://github.com/thecodingmachine/safe.git",
-                "reference": "31d2c13b9e67674614df33ecb3dc0f20f8733749"
+                "reference": "4547d4684086d463b00cbd1a7763395280355e7d"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/thecodingmachine/safe/zipball/31d2c13b9e67674614df33ecb3dc0f20f8733749",
-                "reference": "31d2c13b9e67674614df33ecb3dc0f20f8733749",
+                "url": "https://api.github.com/repos/thecodingmachine/safe/zipball/4547d4684086d463b00cbd1a7763395280355e7d",
+                "reference": "4547d4684086d463b00cbd1a7763395280355e7d",
                 "shasum": ""
             },
             "require": {
@@ -4368,7 +4512,7 @@
                 "MIT"
             ],
             "description": "PHP core functions that throw exceptions instead of returning FALSE on error",
-            "time": "2018-10-30T16:49:26+00:00"
+            "time": "2018-11-13T09:01:03+00:00"
         },
         {
             "name": "theseer/tokenizer",
diff --git a/src/Classification/Ensemble/Bagging.php b/src/Classification/Ensemble/Bagging.php
index 26cc7a6..2c9010d 100644
--- a/src/Classification/Ensemble/Bagging.php
+++ b/src/Classification/Ensemble/Bagging.php
@@ -157,7 +157,7 @@ class Bagging implements Classifier
     {
         $predictions = [];
         foreach ($this->classifiers as $classifier) {
-            /* @var $classifier Classifier */
+            /** @var Classifier $classifier */
             $predictions[] = $classifier->predict($sample);
         }
 
diff --git a/src/Classification/Ensemble/RandomForest.php b/src/Classification/Ensemble/RandomForest.php
index c0f0dd8..ac1304c 100644
--- a/src/Classification/Ensemble/RandomForest.php
+++ b/src/Classification/Ensemble/RandomForest.php
@@ -86,7 +86,7 @@ class RandomForest extends Bagging
         // Traverse each tree and sum importance of the columns
         $sum = [];
         foreach ($this->classifiers as $tree) {
-            /* @var $tree DecisionTree */
+            /** @var DecisionTree $tree */
             $importances = $tree->getFeatureImportances();
 
             foreach ($importances as $column => $importance) {
diff --git a/src/Clustering/FuzzyCMeans.php b/src/Clustering/FuzzyCMeans.php
index db42fe9..3637ef6 100644
--- a/src/Clustering/FuzzyCMeans.php
+++ b/src/Clustering/FuzzyCMeans.php
@@ -18,7 +18,7 @@ class FuzzyCMeans implements Clusterer
     private $clustersNumber;
 
     /**
-     * @var array|Cluster[]
+     * @var Cluster[]
      */
     private $clusters = [];
 
@@ -28,7 +28,7 @@ class FuzzyCMeans implements Clusterer
     private $space;
 
     /**
-     * @var array|float[][]
+     * @var float[][]
      */
     private $membership = [];
 
diff --git a/src/Clustering/KMeans/Space.php b/src/Clustering/KMeans/Space.php
index 566d691..f9f57f5 100644
--- a/src/Clustering/KMeans/Space.php
+++ b/src/Clustering/KMeans/Space.php
@@ -116,7 +116,7 @@ class Space extends SplObjectStorage
     }
 
     /**
-     * @return array|Cluster[]
+     * @return Cluster[]
      */
     public function cluster(int $clustersNumber, int $initMethod = KMeans::INIT_RANDOM): array
     {
@@ -129,7 +129,7 @@ class Space extends SplObjectStorage
     }
 
     /**
-     * @return array|Cluster[]
+     * @return Cluster[]
      */
     protected function initializeClusters(int $clustersNumber, int $initMethod): array
     {
diff --git a/src/CrossValidation/StratifiedRandomSplit.php b/src/CrossValidation/StratifiedRandomSplit.php
index 4974d4c..3b3acc4 100644
--- a/src/CrossValidation/StratifiedRandomSplit.php
+++ b/src/CrossValidation/StratifiedRandomSplit.php
@@ -19,7 +19,7 @@ class StratifiedRandomSplit extends RandomSplit
     }
 
     /**
-     * @return Dataset[]|array
+     * @return Dataset[]
      */
     private function splitByTarget(Dataset $dataset): array
     {
diff --git a/src/Math/Statistic/ANOVA.php b/src/Math/Statistic/ANOVA.php
index f7b01c7..d233f84 100644
--- a/src/Math/Statistic/ANOVA.php
+++ b/src/Math/Statistic/ANOVA.php
@@ -17,9 +17,9 @@ final class ANOVA
      * the same population mean. The test is applied to samples from two or
      * more groups, possibly with differing sizes.
      *
-     * @param array|array[] $samples - each row is class samples
+     * @param array[] $samples - each row is class samples
      *
-     * @return array|float[]
+     * @return float[]
      */
     public static function oneWayF(array $samples): array
     {
diff --git a/src/Math/Statistic/Correlation.php b/src/Math/Statistic/Correlation.php
index 7039e39..6878388 100644
--- a/src/Math/Statistic/Correlation.php
+++ b/src/Math/Statistic/Correlation.php
@@ -9,8 +9,8 @@ use Phpml\Exception\InvalidArgumentException;
 class Correlation
 {
     /**
-     * @param array|int[]|float[] $x
-     * @param array|int[]|float[] $y
+     * @param int[]|float[] $x
+     * @param int[]|float[] $y
      *
      * @throws InvalidArgumentException
      */
diff --git a/src/Math/Statistic/StandardDeviation.php b/src/Math/Statistic/StandardDeviation.php
index 170a9ee..a9724d1 100644
--- a/src/Math/Statistic/StandardDeviation.php
+++ b/src/Math/Statistic/StandardDeviation.php
@@ -9,7 +9,7 @@ use Phpml\Exception\InvalidArgumentException;
 class StandardDeviation
 {
     /**
-     * @param array|float[]|int[] $numbers
+     * @param float[]|int[] $numbers
      */
     public static function population(array $numbers, bool $sample = true): float
     {
@@ -39,7 +39,7 @@ class StandardDeviation
      * Sum of squares deviations
      * ∑⟮xᵢ - μ⟯²
      *
-     * @param array|float[]|int[] $numbers
+     * @param float[]|int[] $numbers
      */
     public static function sumOfSquares(array $numbers): float
     {
diff --git a/src/Pipeline.php b/src/Pipeline.php
index d57da87..41188f3 100644
--- a/src/Pipeline.php
+++ b/src/Pipeline.php
@@ -7,7 +7,7 @@ namespace Phpml;
 class Pipeline implements Estimator
 {
     /**
-     * @var array|Transformer[]
+     * @var Transformer[]
      */
     private $transformers = [];
 
@@ -17,7 +17,7 @@ class Pipeline implements Estimator
     private $estimator;
 
     /**
-     * @param array|Transformer[] $transformers
+     * @param Transformer[] $transformers
      */
     public function __construct(array $transformers, Estimator $estimator)
     {
@@ -39,7 +39,7 @@ class Pipeline implements Estimator
     }
 
     /**
-     * @return array|Transformer[]
+     * @return Transformer[]
      */
     public function getTransformers(): array
     {