Types of Questions in Computer Science Education - Guide to Teaching Computer Science: An Activity-Based Approach - page 162

Discussion : The fact that students should relate to a given module influences the
development process of the solution. For example, in the case of a given method, as
in the above example, the learner has to suit the developed method to a specific sub-
task that the given method implements. This type of questions is considered harder
than Type1 questions because in this case learners need to meet a constraint—the
use of the given subtask.

9.2.3 Type3. Tracing a Given Solution

Description : A given code is presented and the learners are asked to track the code
execution.
Example of a general pattern : Present a tracing table that follows the execution
of a given method. The table should include a column for each variable and for the
code output.
Variations : A tracing question can ask to follow, for example: (a) a complete pro-
gram; (b) a single method; (c) a recursive method; (d) object creation. In addition,
the following instructions can be used in each of the above variations: (1) follow
the code execution according to a given input; (2) follow the code execution when
learners choose the input; (3) follow the code execution according to several differ-
ent specified inputs which are selected in a way that guides the learners to find what
the given code performs; (4) find different sets of inputs so that each set represents
a different flow by which the code is executed; (5) find a set of inputs that yields a
specific output.
Discussion : Variations (1)-(3) can be considered as closed questions. The learner
is required to trace a given code with a specified (given or chosen) input, and there
is only one correct solution. Variations (4) or (5) require learners to apply deeper
considerations and to examine the presented code from a higher level of abstrac-
tion. In these cases, it is not sufficient to understand different instructions; rather,
they require code analysis—what the purpose of the code is and how it is achieved.
Clearly, more advanced cognitive skills are needed in order to address meaningfully
these variations.

9.2.4 Type4. Analysis of Code Execution

Description : A given code is presented and learners are asked to analyze specific
aspects of the code execution.
Example of a general pattern : Look at the given code that includes a loop and
answer the following questions:

1. For what values of x and y the loop is not executed at all?
2. For what values of x and y the loop is executed exactly one time?
3. For what values of x and y the loop will never terminate?