Here is a numbers quiz: 70, 74, 78, 65, 63, 61, 65, 75, 67, 60. (Hint: It is not about maths.)
If you have been following the political news closely, it is not hard to guess that the figures represent the People's Action Party's (PAP's) percentage share of the valid votes in past elections.
With campaigning for the Sept 11 General Election set to intensify in the coming week, this numbers game will be making the rounds. How many seats will the PAP and opposition parties get, how much share of the popular vote, and what sort of swing will we see, if any?
While the general election is serious business about issues concerning Singapore's leadership, the future of multiparty politics, and even about the next 50 years, the reality is that when the ballots are finally counted, all eyes will be on these numbers.
And indeed when you look closely at the 10 numbers listed, they tell quite a story.
Here is one observation: There were four large swings in those 10 general elections.
In 1984, the ruling party suffered a 13-percentage-point swing against it, down from 78 per cent to 65 per cent.
That was the year it failed to regain Anson, which the Workers' Party (WP) represented by Mr J.B. Jeyaretnam had won in a by-election in 1981, and it lost Potong Pasir to the resolute Mr Chiam See Tong.
Its share of the votes then continued to fall in the next two general elections.
But it bounced sky high to 75 per cent in 2001, a huge swing of 10 percentage points.
This was followed by two other large swings, but this time downwards, of 8 and 7 percentage points in 2006 and 2011.
Here are the numbers again with those swings in brackets: 70, 74, 78, 65 (-13), 63, 61, 65, 75 (+10), 67 (-8), 60 (-7).
What can we draw from this?
It has been said that Singapore is a politically flat country, meaning that, unlike in some geographically big places where there are politically diverse areas, Singapore is so small and homogeneous, you cannot tell the difference between Jurong and East Coast in the same way you could between liberal New York and conservative Texas. New York will almost certainly vote Democratic, while Texas will go Republican.
For Singapore, there is no such division. It also means that if there was one big issue in an election, it could affect every constituency the same way, thus resulting in those big swings nationwide.
That was how the 10-percentage- point surge in PAP's vote in 2001 was explained - fear gripped the country after the Sept 11 attack in the United States, and voters fled to the safety of the ruling party.
One issue, one large swing.
It was also how the 2011 swing against the PAP was accounted for - widespread unhappiness over its immigration, housing and transport policies, and significant numbers switched to the WP.
These type of large swings seldom result from voters making rational and deliberate calculations about the pluses and minuses of policies or the manifestos of the different parties.
There are too many people with different ideas about which policies they like or dislike to cause all of them to think alike.
Instead, they are about sentiment and mood, about emotions that have to do with trust or distrust, happiness or disgust, like or dislike, and all those other feelings that make up how a person feels about something or somebody.
When the mood was nervous anxiety over whether global terrorism would prevail in 2001, or when it turned sour in 2011 against the ruling party, the numbers swung upwards and downwards accordingly.
So, what is the likelihood of the electoral needle swinging wildly this general election?
Given what has happened this year, the conditions do exist for a mood change.
After all, the country had never experienced such a collective and public outpouring of emotion when its founding prime minister, Mr Lee Kuan Yew, died in March.
Then, there were the Jubilee year celebrations with goodies to go, including those mentioned by the Prime Minister last Sunday at the National Day Rally.
Would they work up a feel-good attitude towards the party?
There is one problem with this view, though.
Research has shown that there is a negative bias in how people vote, meaning that they are more likely to be influenced by what they do not like about a candidate or a party than what they like about them.
In many years of study and experiments on this, political scientist Jon Krosnick at Stanford University has shown that if you like two candidates equally, there is little motivation to go out and vote for either one of them.
That is not surprising. Even when you like them unequally, you will not feel very strongly about voting for the one you like more. But when you dislike one of them, that is when you become a very engaged voter.
Here is how he puts it: "If you dislike at least one of the two candidates, then you really are motivated to participate - so, in other words, it is really disliking the candidate that motivates turnout."
Negative mood has a stronger impact on election results than positive sentiment, and it explains those large swings in the past.
This has important implications for the Sept 11 polls.
For the PAP, it means moderating expectations on how the Jubilee year celebrations might sway voters. It also means not doing anything that will bring forth negative perceptions of the party, which might trigger the "dislike" behaviour that Mr Krosnick referred to.
This includes toning down personal attacks on political opponents, which it sometimes did in past elections, causing a voter backlash.
For a dominant party like the PAP, coming across as a big bully can cause an adverse mood change.
For the opposition, you can expect it to play up the ruling party's perceived failings and try to get voters to dislike the PAP.
But while negative campaigning might seem the more effective strategy in theory, there is also the possibility that it can backfire and lose votes.
How the parties balance the urge to attack their opponents without damaging their own cause will be an interesting aspect of the campaigning.
Watch out for those mood swings in the next 12 days.
This article was first published on August 30, 2015.
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