Pedagogical reasons for time-limited exams

Question

Reading the various questions about open-book and closed-book examinations got me wondering:

Is there any sound pedagogical reason for a time-limited examination (closed or open) at the undergraduate/advanced UG level ?

I understand that there are many good logistical reasons, including:

• classroom management in a big group
• a desire to prevent cheating

and at (say) the elementary school level, I understand that timed tests (say of multiplication tables) create a certain level of felicity with manipulating numbers that helps with more complex tasks later on.

But at the UG/advanced UG level, it seems to me that deep understanding is usually more important.

Note: This question on the unreasonableness of the prescribed time limits is related, but not exactly the same (i.e it takes as given the existence of time limits and merely questions the actual time span set)

Answer 1

Is there any sound pedagogical reason for a time-limited examination (closed or open) at the undergraduate/advanced UG level ?

For many subjects, yes. For others, no.

I had an exam for a subject in school called "technical graphics". It involved drawing parabolas and projections and so forth on a big sheet of A3 paper with pencils and protractors and compasses. It was widely-regarded to be a subject of skill more than knowledge: the exam was timed and you had to accurately and quickly and carefully draw up four or five questions. A small inaccuracy becomes compounded through the rest of the drawing. Given unlimited time and some basic knowledge, nearly anyone could ace the exam since acquiring the necessary knowledge was easy; but acquiring the skill to do the timed exam was hard. And it was the skill we practised in class. Was this skill useful? Was it a learning outcome to draw quickly? I would say yes, of course; if I were to become a draughtsman (leaving aside CAD et al. for the purposes of the analogy), learning to draw quickly and accurately would be important to my livelihood. And it was the tightly-timed test that put emphasis on this learning outcome.

Likewise if I were doing a cookery lesson, cooking quickly would be important. If I were doing a programming lesson, programming quickly would not be as important, but it would still be important. And so we get into the usual varying shades of grey.

Generalising, we can define different types of learning based on the two main types of memory targeted: procedural memory (residing below the level of conscious awareness) and declarative memory (facts and/or knowledge that can be consciously recalled or inferred from other such facts/knowledge). Some subjects – like technical graphics or cookery or programming – put a strong focus on development of procedural memory alongside declarative memory. Other subjects – like biology or history – emphasise declarative memory far far more than procedural memory.

As such, I would say that the importance of a time-limited exam for a subject is correlated with the emphasis on procedural learning for that subject. A teacher may then wish to consider whether or not procedural learning is important for their subject or not.

Answer 2

Oooo. What an intriguing question.

My "answer" is that there is no pedagogical reason, merely practical ones. This is based on the attached study (1) that shows the difficulty with assuming only learning disabled students benefit from more time for exams. Apparently the "time doesn't matter" idea is called the Maximum Potential Thesis.

I certainly am guilty of writing questions that push student time limits to the max... essentially creating a reading exam in addition to a biology one. Student recall of vocabulary and definitions should be quick. But my main learning goal is thoughtful, connected thinking rather than fast thinking.

1. Zuriff, G. E. (2000). Extra examination time for students with learning disabilities: An examination of the maximum potential thesis. Applied Measurement in Education, 13(1), 99-117.

Answer 3

Open book exams

A particular reason for time limits is the open book exam. Such an exam without any time limits would allow the student to simply study all the relevant topics on the spot, and be useless for evaluation; however, an open book exam with an appropriate time limit will separate students based on their knowledge and obtained skill, while allowing the benefits of open-book exams for subjects where people aren't expected to memorize everything but use reference material as needed, and in those disciplines where you should teach students a habit to always doublecheck and verify in case of doubt, instead of guessing, e.g. medicine.

In essence, the time limit is a tool to check if you need to look up 5% of issues or 95%.

Answer 4

I am not sure if in the field of Pedagogy there is any study on the topic, but in the field i studied (Electronic Engineering), doing things fast is very important. Not only you need to be able to understand a topic, but you need to be able to solve problems in a restricted time period, as is the case in the real life profession. When you are working on a project and you need to design something, or are presented with a problem in a system, the engineer in this case needs to be able to identify and solve the problem in the shortest time possible. It is basic competition, "The fast drives out the slow, even if the fast is wrong".

Answer 5

It is often the case that a problem can be solved in multiple ways, some of which involve more "brute force" and some of which involve deeper understanding of the material. The "brute force" approaches are often also much slower than the approaches involving deeper understanding.

Time limits are then one tool that can help to distinguish the depth of understanding that a student has for the material, by making it difficult to accomplish with "brute force" methods in the allotted time.

I had personal experience with this myself as a teaching assistant for the introductory artificial intelligence class at MIT. Many of the things that we taught in that class and the questions that we used to test for them had this property. Students who understood the material well typically finished tests with lots of time to spare and left early, while the ones who were struggling to rediscover the material during the exam came to complain to us afterward about the lack of time --- not the most pleasant thing for any involved, but one that we found no good way to address in the time that I was a TA for that class.