Hierarchical Task Analysis
What is a hierarchical analysis?
"A hierarchy is an organization of elements that, according to prerequisite relationships, describes the path of experiences a learner must take to achieve any single behavior that appears higher in the hierarchy (Seels & Glasgow, 1990, p. 94)". Thus, in a hierarchical analysis, the instructional designer breaks down a task from top to bottom, thereby, showing a hierarchical relationship amongst the tasks, and then instruction is sequenced bottom up. For example, in the diagram below, task 4 has been decomposed into its enabling tasks implying that the learner cannot perform the third task until he/she has performed the first and second tasks respectively.
How do I conduct a hierarchical analysis?
The starting point for constructing a hierarchy is a comprehensive list of the tasks that make up a job or function. There are three major steps to constructing a hierarchy:
1. Cluster or group the tasks. For inclusion in a group, select tasks that bear close resemblance to each other. Each task must be included in at least one of the groups, but a task may also be common to several groups. Label the groups with terms that emerge from the job or function being analyzed. Initial clustering or grouping of tasks may be tentative. The composition of the groups may change as a result of decisions you make later on. Do not hesitate to regroup tasks when it seems appropriate.
2. Organize tasks within each group to show the hierarchical relationships for learning. Ask yourself "What would the learner have to learn in order to do this task?" Once the essential prerequisite relationships are shown, reevaluate the relationship between each pair of tasks with the question "Can this superordinate task be performed if the learner cannot perform this subordinate task?" The lower level skill must be integrally related to the higher-level skill. The learning types (domains) of the tasks should match horizontally.
3. Confer with a subject matter expert to determine the hierarchy’s accuracy. This step occurs concurrently with Steps 1 and 2.
(Seels & Glasgow, 1990)
What criteria should I use to evaluate my analysis?
The following is a checklist for you to evaluate your hierarchical analysis.
_______Adequate breadth (number) of tasks; (0-5)
_______ Depth of levels: does hierarchy span all levels of learning (problem-solving to verbal information) leading to the final level of the task; (0-5)
_______ Validity & accuracy: how well does analysis correspond to learning processes; (0-5)
_______ Consistency in grouping similar tasks on same level in hierarchy; (0-5)
_______ All skills/sub-skills stated in performance terms (using verbs); (0-5)
Can I see an example of a hierarchical task analysis?
By Tina Stanley
Click here for more examples of hierarchical task analyses.