diff --git a/.travis.yml b/.travis.yml
index 7a17dd93..afe5911a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,7 +17,7 @@ before_script:
   - composer install --ignore-platform-reqs
 
 script:
-  - ./vendor/bin/phpunit
+  - ./vendor/bin/phpunit --color=always --coverage-text
 
 jobs:
   include:
diff --git a/composer.json b/composer.json
index d0379949..32df7bac 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,7 @@
     "scripts": {
         "check": [
             "php-cs-fixer fix --ansi --dry-run --diff",
-            "phpcs --report-width=200 samples/ src/ tests/ --ignore=samples/Header.php --standard=PSR2 -n",
+            "phpcs --report-width=200 samples/ src/ tests/ --ignore=samples/Header.php --standard=PSR12 -n",
             "phpunit --color=always"
         ],
         "fix": [
diff --git a/tests/data/Calculation/Statistical/CHIDIST.php b/tests/data/Calculation/Statistical/CHIDIST.php
index 4093b991..023d2a7c 100644
--- a/tests/data/Calculation/Statistical/CHIDIST.php
+++ b/tests/data/Calculation/Statistical/CHIDIST.php
@@ -37,4 +37,8 @@ return [
         '#VALUE!',
         'NAN', 3,
     ],
+    [
+        '#NUM!',
+        -8, 3,
+    ],
 ];