Index: lams_central/conf/language/lams/ApplicationResources.properties
===================================================================
diff -u -r666a01da9d0d2b4482ca00041527739b5e56b9f2 -rb2b9056f147f07040dab6ab9c92d7b505776996f
--- lams_central/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision 666a01da9d0d2b4482ca00041527739b5e56b9f2)
+++ lams_central/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision b2b9056f147f07040dab6ab9c92d7b505776996f)
@@ -943,6 +943,10 @@
 label.qb.stats.usage.difficulty = Difficulty index
 label.qb.stats.usage.discrimination = Discrimination index
 label.qb.stats.usage.biserial = Point biserial
+label.qb.stats.tooltip = Item analysis is a technique that analyses the student answers to evaluate the effectiveness of questions in an exam. Only students who have finished the activity are taken into consideration. There must be at least 2 students.
+label.qb.difficulty.index.tooltip = The difficulty index represents a percentage of the students responses that answered the question correctly. This metric takes a value between 0 and 1. High values indicate that the question is easy, while low values indicate that is difficult. Value 0.3 to 0.7 is considered good for this factor and outside this range requires improvement.
+label.qb.discrimination.index.tooltip = Discrimination index measures how well a question distinguishes between students with more knowledge or skill from those with less. Values close to +1 indicate that the question does a good job of discriminating between high performers and low performers. Value 0.2 to 1 is considered good for this factor, -0.2 to 0.2 is medium and below -0.2 requires improvement.
+label.qb.point.biserial.tooltip = Point-biserial measures the correlation between the scores on the entire exam and the scores on the single question (where 1 = correct answer and 0 = incorrect answer). A large correlation indicates that a question is measuring the same construct as the overall exam measures. Value 0.2 to 1 is considered good for this factor, -0.2 to 0.2 is medium and below -0.2 requires improvement.
 label.qb.stats.versions = Previous versions
 label.qb.stats.versions.none = This question does not have any previous versions
 label.qb.stats.versions.created = Created date
Index: lams_central/web/qb/stats.jsp
===================================================================
diff -u -re96141f945611c4c619dc27b0b2e65edcd6d0150 -rb2b9056f147f07040dab6ab9c92d7b505776996f
--- lams_central/web/qb/stats.jsp	(.../stats.jsp)	(revision e96141f945611c4c619dc27b0b2e65edcd6d0150)
+++ lams_central/web/qb/stats.jsp	(.../stats.jsp)	(revision b2b9056f147f07040dab6ab9c92d7b505776996f)
@@ -313,7 +313,8 @@
 	
 	<div class="panel panel-default">
 		<div class="panel-heading">
-			<fmt:message key="label.qb.stats.usage" />
+			<fmt:message key="label.qb.stats.usage" />&nbsp;
+			<i class="fa fa-question-circle" aria-hidden="true" data-toggle="tooltip" data-placement="right" title="<fmt:message key="label.qb.stats.tooltip" />"></i>
 		</div>
 		<div class="panel-body">
 			<c:choose>
@@ -339,13 +340,16 @@
 								<fmt:message key="label.qb.stats.usage.participant.count" />
 							</th>
 							<th>
-								<fmt:message key="label.qb.stats.usage.difficulty" />
+								<fmt:message key="label.qb.stats.usage.difficulty" />&nbsp;
+								<i class="fa fa-question-circle" aria-hidden="true" data-toggle="tooltip" data-placement="right" title="<fmt:message key="label.qb.difficulty.index.tooltip" />"></i>
 							</th>
 							<th>
-								<fmt:message key="label.qb.stats.usage.discrimination" />
+								<fmt:message key="label.qb.stats.usage.discrimination" />&nbsp;
+								<i class="fa fa-question-circle" aria-hidden="true" data-toggle="tooltip" data-placement="right" title="<fmt:message key="label.qb.discrimination.index.tooltip" />"></i>
 							</th>
 							<th>
-								<fmt:message key="label.qb.stats.usage.biserial" />
+								<fmt:message key="label.qb.stats.usage.biserial" />&nbsp;
+							 	<i class="fa fa-question-circle" aria-hidden="true" data-toggle="tooltip" data-placement="right" title="<fmt:message key="label.qb.point.biserial.tooltip" />"></i>
 							</th>
 						</tr>
 						<c:forEach var="activityDTO" items="${stats.activities}">