Two weeks after the national redelineation exercise since 13 years was announced, the Election Commission (EC) has come under fire for malapportionment.

Malapportionment entails having vast differences between the number of voters from one constituency to another.

This is unfair because it dilutes the value of votes in larger constituencies compared to smaller constituencies.

For example, after the redelineation, the parliamentary seat of Damansara (formerly Petaling Jaya Utara) which has 150,439 voters will only get to elect one MP to Parliament whereas Putrajaya, which only has 17,627 voters, will also get one MP.

While this example has been repeated often, it does not reflect the overall malapportionment as it is only a comparison between two extreme cases in a total of 222 parliamentary seats.

However, there is a formula that can explain the overall severity of malapportionment with a single value.

The higher this value is, the worse the malapportionment. The lower the value, the more equal the respective parliamentary seats are.

Quantifying the discrepancy

For illustration, Malaysia's latest redelineated boundaries will have a malapportionment value of 0.141. This is compared to Australia (0.025), UK (0.0425) and Canada (0.06).

These malapportionment values shed light on a series of analyses by Serdang MP Ong Kian Ming, who has a PhD in political science from Duke University, USA.

For Ong’s analysis, he has detailed here how the malapportionment value is calculated:

Step 1: Find out the percentage of a seat. If there are 10 seats in total, then it's one out of 10, or 10 percent. If there are 222 seats, then it’s one out of 222, or 0.45 percent.

Step 2: Find out the percentage of voters in a seat. For example, if there's 1,000,000 voters in a country and this particular seat has 20,000 voters, then it’s two percent.

Step 3: Minus the percentages in step 1 and step 2. Then, note down the absolute value for this seat. It doesn't matter if the value is negative or positive, you only want the number.

Step 4: Repeat this process for all seats. Then add up the absolute value of all seats together.

Step 5: Divide the sum by two. This final number will be the malapportionment value.

The tables below illustrates four different examples based on a hypothetical population of 100,000 with 10 seats.