Implement correct policy regarding whether there exist sufficient data for a measure

app/models/measure.rb

@@ -4,11 +4,19 @@ class Measure < ActiveRecord::Base
 
   has_many :survey_item_responses, through: :survey_items
 
+  def teacher_survey_items
+    @teacher_survey_items ||= survey_items.where("survey_item_id LIKE 't-%'")
+  end
+
+  def student_survey_items
+    @student_survey_items ||= survey_items.where("survey_item_id LIKE 's-%'")
+  end
+
   def includes_teacher_survey_items?
-    survey_items.where("survey_item_id LIKE 't-%'").any?
+    teacher_survey_items.any?
   end
 
   def includes_student_survey_items?
-    survey_items.where("survey_item_id LIKE 's-%'").any?
+    student_survey_items.any?
   end
 end

app/models/survey_item_response.rb

@@ -8,8 +8,8 @@ class SurveyItemResponse < ActiveRecord::Base
 
   scope :for_measures, ->(measures) { joins(:survey_item).where('survey_items.measure_id': measures.map(&:id)) }
   scope :for_measure, ->(measure) { joins(:survey_item).where('survey_items.measure_id': measure.id) }
-  scope :for_teacher_responses_for_measure, ->(measure) { for_measure(measure).where("survey_items.survey_item_id LIKE 't-%'") }
-  scope :for_student_responses_for_measure, ->(measure) { for_measure(measure).where("survey_items.survey_item_id LIKE 's-%'") }
+  scope :teacher_responses_for_measure, ->(measure) { for_measure(measure).where("survey_items.survey_item_id LIKE 't-%'") }
+  scope :student_responses_for_measure, ->(measure) { for_measure(measure).where("survey_items.survey_item_id LIKE 's-%'") }
 
   def self.score_for_measure(measure:, school:, academic_year:)
     return nil unless SurveyItemResponse.sufficient_data?(measure: measure, school: school, academic_year: academic_year)
@@ -26,11 +26,17 @@ class SurveyItemResponse < ActiveRecord::Base
     meets_student_threshold = true
 
     if measure.includes_teacher_survey_items?
-      meets_teacher_threshold = SurveyItemResponse.for_teacher_responses_for_measure(measure).where(academic_year: academic_year, school: school).count >= TEACHER_RESPONSE_THRESHOLD
+      teacher_survey_item_responses = SurveyItemResponse.teacher_responses_for_measure(measure).where(academic_year: academic_year, school: school)
+      average_number_of_survey_item_responses = teacher_survey_item_responses.count / measure.teacher_survey_items.count
+
+      meets_teacher_threshold = average_number_of_survey_item_responses >= TEACHER_RESPONSE_THRESHOLD
     end
 
     if measure.includes_student_survey_items?
-      meets_student_threshold = SurveyItemResponse.for_student_responses_for_measure(measure).where(academic_year: academic_year, school: school).count >= STUDENT_RESPONSE_THRESHOLD
+      student_survey_item_responses = SurveyItemResponse.student_responses_for_measure(measure).where(academic_year: academic_year, school: school)
+      average_number_of_survey_item_responses = student_survey_item_responses.count / measure.student_survey_items.count
+
+      meets_student_threshold = average_number_of_survey_item_responses >= STUDENT_RESPONSE_THRESHOLD
     end
 
     meets_teacher_threshold and meets_student_threshold

spec/features/school_dashboard_feature_spec.rb

@@ -29,33 +29,33 @@ feature 'School dashboard', type: feature do
   let(:password) { 'winchester!' }
 
   before :each do
+    survey_item_responses = []
+
     survey_items_for_measure_1A_i.each do |survey_item|
-      200.times do
-        SurveyItemResponse.create response_id: rand.to_s, academic_year: ay_2020_21, school: school,
-                                  survey_item: survey_item, likert_score: 4
+      SurveyItemResponse::TEACHER_RESPONSE_THRESHOLD.times do
+        survey_item_responses << SurveyItemResponse.new(response_id: rand.to_s, academic_year: ay_2020_21, school: school, survey_item: survey_item, likert_score: 4)
       end
     end
 
     survey_items_for_measure_2A_i.each do |survey_item|
-      200.times do
-        SurveyItemResponse.create response_id: rand.to_s, academic_year: ay_2020_21, school: school,
-                                  survey_item: survey_item, likert_score: 5
+      SurveyItemResponse::STUDENT_RESPONSE_THRESHOLD.times do
+        survey_item_responses << SurveyItemResponse.new(response_id: rand.to_s, academic_year: ay_2020_21, school: school, survey_item: survey_item, likert_score: 5)
       end
     end
 
     survey_items_for_measure_4C_i.each do |survey_item|
-      200.times do
-        SurveyItemResponse.create response_id: rand.to_s, academic_year: ay_2020_21, school: school,
-                                  survey_item: survey_item, likert_score: 1
+      SurveyItemResponse::TEACHER_RESPONSE_THRESHOLD.times do
+        survey_item_responses << SurveyItemResponse.new(response_id: rand.to_s, academic_year: ay_2020_21, school: school, survey_item: survey_item, likert_score: 1)
       end
     end
 
     survey_items_for_subcategory.each do |survey_item|
       200.times do
-        SurveyItemResponse.create response_id: rand.to_s, academic_year: ay_2020_21, school: school,
-                                  survey_item: survey_item, likert_score: 4
+        survey_item_responses << SurveyItemResponse.new(response_id: rand.to_s, academic_year: ay_2020_21, school: school, survey_item: survey_item, likert_score: 4)
       end
     end
+
+    SurveyItemResponse.import survey_item_responses
   end
 
   scenario 'User authentication fails' do

spec/models/survey_item_response_spec.rb

@@ -11,26 +11,71 @@ describe SurveyItemResponse, type: :model do
       let(:teacher_survey_item_2) { create(:survey_item, survey_item_id: 't-question-2', measure: measure) }
       let(:teacher_survey_item_3) { create(:survey_item, survey_item_id: 't-question-3', measure: measure) }
 
-      context 'and there is sufficient teacher data' do
+      context "and the number of responses for each of the measure's survey items meets the teacher threshold of 17" do
         before :each do
-          4.times do
+          17.times do
             create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school, likert_score: 3)
-            create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school, likert_score: 5)
-            create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: 3)
-            create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: 5)
           end
+          17.times do
             create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: 4)
           end
+          17.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_3, academic_year: ay, school: school, likert_score: 5)
+          end
+        end
 
         it 'returns the average of the likert scores of the survey items' do
           expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to eq 4
         end
       end
 
-      context 'and there is insufficient teacher data' do
+      context "and the average number of responses across the measure's survey items meets the teacher threshold of 17" do
         before :each do
-          (SurveyItemResponse::TEACHER_RESPONSE_THRESHOLD - 1).times do
-            create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school)
+          19.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school, likert_score: 3)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: 4)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_3, academic_year: ay, school: school, likert_score: 5)
+          end
+        end
+
+        it 'returns the average of the likert scores of the survey items' do
+          average_score = 3.941
+          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to be_within(0.001).of(average_score)
+        end
+      end
+
+      context "and none of the measure's survey items meets the teacher threshold of 17" do
+        before :each do
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school, likert_score: rand)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: rand)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_3, academic_year: ay, school: school, likert_score: rand)
+          end
+        end
+
+        it 'returns nil' do
+          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to be_nil
+        end
+      end
+
+      context "and the average number of responses across the measure's survey items does not meet the teacher threshold of 17" do
+        before :each do
+          18.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_1, academic_year: ay, school: school, likert_score: rand)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_2, academic_year: ay, school: school, likert_score: rand)
+          end
+          16.times do
+            create(:survey_item_response, survey_item: teacher_survey_item_3, academic_year: ay, school: school, likert_score: rand)
           end
         end
 
@@ -43,26 +88,73 @@ describe SurveyItemResponse, type: :model do
     context 'when the measure includes only student data' do
       let(:student_survey_item_1) { create(:survey_item, survey_item_id: 's-question-1', measure: measure) }
       let(:student_survey_item_2) { create(:survey_item, survey_item_id: 's-question-2', measure: measure) }
+      let(:student_survey_item_3) { create(:survey_item, survey_item_id: 's-question-3', measure: measure) }
 
-      context 'and there is sufficient student data' do
+      context "and the number of responses for each of the measure's survey items meets the student threshold of 196" do
         before :each do
-          (SurveyItemResponse::STUDENT_RESPONSE_THRESHOLD/4).times do
-            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: 1)
-            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: 5)
-            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: 1)
-            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: 5)
+          196.times do
+            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: 3)
+          end
+          196.times do
+            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: 4)
+          end
+          196.times do
+            create(:survey_item_response, survey_item: student_survey_item_3, academic_year: ay, school: school, likert_score: 5)
           end
         end
 
         it 'returns the average of the likert scores of the survey items' do
-          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to eq 3
+          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to eq 4
         end
       end
 
-      context 'and there insufficient student data' do
+      context "and the average number of responses across the measure's survey items meets the student threshold of 196" do
         before :each do
-          (SurveyItemResponse::STUDENT_RESPONSE_THRESHOLD - 1).times do
-            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school)
+          200.times do
+            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: 3)
+          end
+          195.times do
+            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: 4)
+          end
+          193.times do
+            create(:survey_item_response, survey_item: student_survey_item_3, academic_year: ay, school: school, likert_score: 5)
+          end
+        end
+
+        it 'returns the average of the likert scores of the survey items' do
+          average_score = 3.988
+          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to be_within(0.001).of(average_score)
+        end
+      end
+
+      context "and none of the measure's survey items meets the student threshold of 196" do
+        before :each do
+          195.times do
+            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: rand)
+          end
+          195.times do
+            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: rand)
+          end
+          195.times do
+            create(:survey_item_response, survey_item: student_survey_item_3, academic_year: ay, school: school, likert_score: rand)
+          end
+        end
+
+        it 'returns nil' do
+          expect(SurveyItemResponse.score_for_measure(measure: measure, school: school, academic_year: ay)).to be_nil
+        end
+      end
+
+      context "and the average number of responses across the measure's survey items does not meet the student threshold of 196" do
+        before :each do
+          200.times do
+            create(:survey_item_response, survey_item: student_survey_item_1, academic_year: ay, school: school, likert_score: rand)
+          end
+          196.times do
+            create(:survey_item_response, survey_item: student_survey_item_2, academic_year: ay, school: school, likert_score: rand)
+          end
+          191.times do
+            create(:survey_item_response, survey_item: student_survey_item_3, academic_year: ay, school: school, likert_score: rand)
           end
         end