The four levels of Kirkpatrick's evaluation model of training essentially measures:

Reaction of student - what they thought and felt about the training usually done through evaluation forms (Happy sheets)

Learning - the resulting increase in knowledge or capability. 

Behaviour - extent of behaviour and capability improvement and implementation/application

Results - the effects on the business or environment resulting from the trainee's performance. 

All these measures are recommended for a full and meaningful evaluation of learning in organizations, although their application broadly increases in complexity, and usually cost, through the levels from level 1- 4.

Level Objective of Measurement Tools or techniques Comments
Level 1 : Reaction ( and planned action ) Participant's reaction to and satisfaction with the content and delivery of training Evaluation forms or action plans for implementing new knowledge Subjective but has some usefulness
Level 2 : Learning Skills, Knowledge or attitude changes as a result of training program Tests via paper and pencil or computerized format. Tests must be assessed for validity and reliability
Level 3 : Behavior Changes in behavior on the job as a result of training Performance reviews and observations Assumptions is that if the skills are applied, results will follow.
Level 4 : Results - Business Impact Impact of training on business activities and processes. Cost Reduction, productivity increases,improved quality, reduced labor hours,decreased production/processing time,..etc. Critical tasks are isolating the effects of training and capturing appropriate data.
Return on Investment (ROI) Compares the costs of the training program with monetary results and is usually expressed as a percentage Detailed, comprehensive data collection and analysis of costs & benefits accounting expertise helpful. Time Value of money is a factor. The most comprehensive and objective evaluation technique, but the process can be very costly and time consuming.