Demographic advantage of 4.8% vote swing to Opposition in 2016 Elections

by Helluo Librorum

It is clear, from various online polls conducted during and after the recent General Elections, that Singaporean netizens are overwhelmingly pro-Alternative (Opposition) Parties (i.e. against PAP). Consistently, over 90% of the netizens support the Alternatives in these polls.

[Of particular significance are two online surveys:

Yawning Bread's post-polling-day survey (here and here) shows 7.05% (122) voted for PAP, and 92.95% (1609) voted for Alternatives.

Stephan Ortmann (City University of Hong Kong)'s pre-polling-day survey (here) shows  5.83% (78)  pro_PAP, and 94.17% (1260) pro-Alternatives.

Using various internal indicators, I think these surveys capture representative samples of internet-savvy Singaporeans, which I think the vast majority of future young voters will be.]

Netizens are disproportionately younger than the general electorate.

In five years' time, a new cohort of internet-savvy young people will have become new voters, and be predisposed to vote for the Alternatives.

This demographic factor naturally favours the Alternatives. But how big an advantage is it?

My rough estimate is that, assuming that the new 2016 voters are 90% pro-Alternatives, while the old voters (already voting in 2011) remain 39.86% pro-Alternatives, then the 2016 voters overall will be 44.62% pro-Alternatives, a significant swing of 4.76% towards the Alternatives.

Hence, there is a demographic advantage of a 4.8% vote swing to the Alternatives in 2016.

Persuading voters beyond the reach of the internet to support the Alternatives is crucial and laborious. On the other hand, reaching young voters via the internet is far easier, and extremely important, in terms of the sheer number of young voters.

[Remark

Even though new voters provide a significant boost to the Alternative vote share, the old voters remain indispensable in any Alternative Party's electoral victory.

For an Alternative Party to obtain 50%, 55%, 60% of the total vote share, it must have 45.8%, 51.3%, and 56.9% (respectively) share of the old voters. ]

My calculations

First, I estimate the number of new 2016 voters.

The 2010 census (here) shows 243141 citizens aged 15.0-19.9.  New 2016 voters were aged 15.5 to 20.5 during the census.  So I take 243141 as the number of new voters.

(The census show 263750 residents (citizens and PR) aged 15.0-19.9, and 263017 residents aged 16.0-20.9. Thus the number of residents aged 15.5-20.5 can be fairly accurately estimated using either number.)

Next, how many voters will there be in 2016?

From 2001 to 2006, voter number increased by 6.029%. From 2006 to 2011, voter number increased by 8.851% to 2,350,873. (source)

Assuming 8.85% increase from 2011 to 2016, there will be 2,558,925 voters in 2016.

New voters will therefore be 9.50% (=243141/2558925) of the 2016 voters.

Assume that these 9.5% new voters are 90% pro-Alternatives, and the remaining 90.5% old voters are  39.86% pro-Alternatives, then overall the 2016 voters are 44.62% pro-Alternatives. (9.5x90+90,5x39.86=4462.33)

Related post: Young voters (aged 21.0 to 25.9) were responsible for 4.5% vote swing in 2011 Elections (here)