WHILE I agree with Ms Elizabeth Tan Boon Kwan's assertion that overly strict marking may have a negative effect on a student's desire to learn, I fear she has conflated rigidity with rigour in marking - especially in the context of the examples she has raised ("Rigid marking kills interest in science"; Forum Online, last Saturday).
In her first example, she equated a clear liquid with a colourless liquid. Unfortunately, these two terms describe different aspects of a liquid.
A liquid can be both clear and coloured at the same time.
For example, think of a rose syrup drink. It is pinkish-red throughout, meaning that it is not colourless, but you can see through it and there are no visibly suspended particles, making it clear.
Thus, there is a meaningful difference between the two words in the scientific context.
Similarly, in her second example, the author asks if there is a difference between "fair" and "reliable" tests.
For a scientific experiment, the two are conceptually different.
A fair test means one has done things such as control the variables of the experiment correctly; a reliable test is one that returns the same results each and every time it is done.
A poorly designed experiment repeated many times may return the same results each time, but it does not mean the results are fair.
Since the question asked why the test was conducted multiple times, reliability is the concept being tested for.
The latter example is particularly important because fairness and reliability are cornerstones of the scientific method. It is essential that our students learn to distinguish between the two.
Daryl Lim
