The Elections Department released early indications of polling results for the first time during the 2015 General Elections by publicly announcing the result of sampling checks within 2 hours of the close of polls. Sampling checks have been carried out since 2001 or earlier, but the results were not made known to all candidates or the public until this year. The sampling check is carried out by Counting Assistants drawing a sample of 100 ballots from each counting table after opening the ballot boxes and mixing the ballot papers together. As each counting table corresponds to one polling district and there are about 2,000-3,000 voters per polling station, the 100-ballot sample per polling district corresponds to 3-4% of votes cast and is a large enough sample to make a good estimate of the final polling result
As shown in Table 1, the margin of error varies from ±1.2% points for a large GRC, Pasir Ris-Punggol with 66 polling districts, to ±4.4 % points for Potong Pasir, the smallest Single Member Constituency (SMC) with only 5 polling districts. For simplicity, no adjustments are made to account for the variation in number of voters in each polling district, and the error margin is calculated for a 50:50 vote split. The Straits Times has reported that the error margin for sampling counts is ±4% but this is a worst case and only applies to Potong Pasir which is the smallest SMC by far. On average, the uncertainty in the sampling check is within 1.3% points for GRCs and 3.3% points for SMCs.
|Table 1 – Error margins for selected constituencies and SMC and GRC averages|
|Number of polling districts||Sample size||Margin of error at 50% vote share|
|Pasir Ris-Punggol GRC||66||6,600||1.2%|
|East Coast GRC||32||3,200||1.7%|
|Bukit Panjang SMC||11||1,100||3.0%|
|Potong Pasir SMC||5||500||4.4%|
|Error margin is calculated as half the width of the two-sided 95% confidence interval (Normal approximation) at 50% vote share. All polling districts within a constituency are assumed to have an equal number of voters.|
In a first-past-the-post election, however, what counts is not the actual vote share but crossing the 50% threshold. If we ignore three-cornered fights and make use of the normal approximation again, we can calculate a “victory threshold” or minimum sampling check result for which a candidate can be 95% certain of victory. This is shown in Table 2 for selected constituencies. Note that the victory threshold is slightly lower than would be obtained if we simply added the error margin from Table 1 to 50% because the victory threshold is a one-sided rather than a two-sided test. If you’re not statistically-inclined, don’t worry about it – that effect is small in this case. In Aljunied, despite the appearance of a nail-biting finish, the 52:48 sampling check result was above the victory threshold for the Workers’ Party and the PAP in fact had only a 0.2% chance of winning in that constituency once the sampling check result was known [See note 1]. In Punggol East, however, the sampling check result of 51% for PAP was lower than the victory threshold of 52.4% and the PAP could only be 75% certain that they would win there. Put another way, Lee Li Lian still had a 25% chance of winning even after seeing the sampling check results. In all the other constituencies, the winning party’s sampling check result significantly exceeded the victory threshold so the final result was not in doubt once the sampling checks were completed.
|Table 2 – Victory threshold for selected constituencies.|
|No. of polling districts||Victory threshold||Actual PAP share in sampling check||Probability of PAP win given sampling check result|
|Pasir Ris-Punggol (6-member GRC)||66||51.0%||73%||100%|
|Aljunied (5-member GRC)||50||51.2%||48%||0.2%|
|East Coast (4-member GRC)||32||51.5%||61%||100%|
|Sengkang West (SMC)||13||52.3%||63%||100%|
|Punggol East (SMC)||12||52.4%||51%||75%|
|Potong Pasir (SMC)||5||53.7%||68%||100%|
|1. Victory threshold is defined as the minimum sample count result for which a candidate can be 95% certain of receiving over 50% of the actual vote (one-sided test).|
|2. Probability of PAP win is the probability that the actual PAP vote share is > 50%, given the observed sampling check result.|
The error between the sampling check and the actual result gets smaller as the sample size increases. Hence GRCs will have smaller error margins than SMCs and 6-member GRCs will have smaller error margins than 3-member GRCs. This is seen in Figure 1 where the difference between the sampling check and the actual result was only 0.1% points in the 6-member Pasir Ris-Punggol GRC while the largest difference of 2.6% points was observed in MacPherson SMC. The observed differences between sampling check and actual vote counts were all within the expected 95% error margins except for one constituency, but one out of 29 is about right, statistically. We also did not take rounding errors into account, which slightly widen the margin of error.
The sample check is a form of a quick count, which is used in developing democracies where there are concerns with regards to the compilation of electoral results by the central government. In Singapore’s case, there is no obvious need for a quick count as the entire counting process can be observed by candidates’ counting agents and elections results have always been announced within a few hours. Nonetheless, given that the Elections Department has chosen to conduct sampling checks, the decision to publicly reveal sampling check results is a welcome one.
 Some additional uncertainty is caused by the sampling check results only being reported as whole number percentages. The true PAP sampling check result from 5,000 samples could have been as high as 48.5% rather than the reported 48%. However, this would still have given the PAP only a 1.8% chance of victory once the sampling check results were known.
Sampling check results and actual vote counts are tabulated in Sample check vs actual v3 (Excel format).
A version of this note was previously published on The Online Citizen, http://www.theonlinecitizen.com/2015/09/how-accurate-is-the-ge-sample-vote-count/.
Filed under: Elections, General Elections, Sampling check, Validity check | Leave a Comment
DOS does not publish breakdowns of citizen population by age group. The published population pyramids are for “residents” which includes permanent residents. However, the government did publish the actual number of Singapore citizens aged 20-64 in 2011 in the population white paper together with forecasts up to 2060. Chart 6 shows their forecast for the number of citizens aged 20-64 in 2015 as around 2.2 million (I use their scenario with maximum intake of new citizens). The ratio of working-age to elderly citizens is around 5 in Chart 8. This allows us to estimate the total number of Singapore citizens 20 and above in 2015 as 2.64 million. An ELD press release on 27 July 2015 states that there are 2,460,977 electors on the electoral register. Thus, approximately 2.46/2.64 = 93% of Singaporeans of voting age are on the electoral register. For simplicity, I’m not adjusting the denominator for those above 20 but below 21.
Apart from those who were dropped from the the electoral register for failing to vote in previous elections, various other categories of people are not eligible to vote (Section 6 of the Parliamentary Election Act), but the biggest category are probably prisoners. The total number of prisoners (including drug detainees) in Singapore is around 10,000 so that should not affect the figure that much. I presume that the NPTD population figures do not include overseas Singaporeans, so that would not contribute to the missing 7% either. The predominant explanation for voting-age Singaporeans not included in the electoral register is probably be that they failed to vote in previous elections but did not apply to restore their names to the electoral register by choice, ignorance or inability to pay the $50 fee required. 93% registration is high by international standards, but does seem a bit low considering that Singaporeans are automatically enrolled when they turn 21 and only drop off (mostly) if they fail to vote without reasonable excuse.
The International Institute for Democracy and Electoral Assistance (International IDEA) has published a table showing that only about half of Singapore’s voting-age population actually voted. While the first three columns are consistent with ELD figures, the fifth column, Voting Age Population, appears to have been derived by subtracting the number of residents below 21 from the total population including non-citizens. The high proportion of non-citizens (including PRs) living in Singapore, especially in the working age population, therefore inflates the denominator and the low Voting-Age-Population turnout calculated by IDEA may be literally true but not meaningful because a large proportion of the denominator are non-citizens. The numerator is also only for voters in contested constituencies. The voter participation rate is thus further reduced by the prevalence of walkovers in past elections.
(Documenting here for reference as the question came up in discussion recently)
Filed under: Elections, General Elections | Leave a Comment
Tags: Electoral participation
UPDATE: The EBRC report has been released. See comments at bottom of post.
The Elections Department (ELD) recently published revisions to polling districts. This revision comes six months after the last revision in February, which is an unusually short interval as previous revisions were spaced a year or more apart. Polling districts (PDs), also known as precints, are sub-divisions within constituencies and their main significance is that all voters in a polling district will vote at the same polling place within a polling station. Changes to constituency boundaries are normally made by rearranging polling districts into different constituencies so that ELD will not have to compile new electoral registers before the next election. However, changes to precint boundaries do not necessarily mean that those precints will be moved to a different constituency. As usual, ELD did not highlight the changes that were made, but a quick comparison of the July notificaton with the previous February one shows changes in the following polling districts.
|Choa Chu Kang GRC||CK10,CK11|
|East Coast GRC||EC01, EC41|
|Jurong GRC||JR10, JR11|
|Moulmein-Kallang GRC||MK03, MK05|
|Nee Soon GRC||NS53|
|Pasir Ris-Punggol||PN69, PN70|
|Sembawang||SB02, SB03, SB18, SB21, SB22|
|Tanjong Pagar||TP12, TP13|
(If readers spot any other changes which I missed, please drop me a note at email@example.com) Many of the changes do seem to be errata in the sense of just being minor clarifications or streamlining of precint boundaries. However, there are some which could foreshadow changes in constituency boundaries.
The scenic polling district with nobody living in it
Pulau Serangoon (Coney Island) has been cut out of polling district EC01 and placed into its own precint, EC41. This is quite strange because I’m quite sure no one actually lives there right now. While part of it is zoned for residential use, it will probably remain a “rustic park” for several more years. Why carve it out into its own precint now ? My guess is that the intention is to move it from East Coast GRC into a new Punggol GRC so that it can be managed together with the rest of Punggol New Town. The electoral register is not publicly accessible so I do not know the actual number of electors living in Punggol estate but there are only 24 polling districts, which may be just enough for a 3-member GRC.
Hougang, Sengkang, Pasir Ris, Where Am I ?
Talking of Pasir Ris-Punggol GRC, that GRC includes one-third of Sengkang new town and stretches all the way to Hougang Ave 8. Two of the PD’s at the border of Sengkang and Hougang estates were also rationalised in the recent revision. PN69 previously included a condominium and nursing home north of Buangkok Drive as well as 9 HDB blocks along Hougang Ave 8. In the latest revision, that PD was redrawn to include only the condo and nursing home between Compassvale Bow and Buangkok Drive. The HDB blocks in Hougang Ave 8/10 were consolidated into one precint, PN70. This seems unusual to me because the new PN69 polling district comprises one condo with 625 units, and a relatively small (72-bed) nursing home while PN70 consists of 24 HDB blocks. If the intent of tweaking polling districts is to balance out the distribution of voters, this change would seem to go against that. Interestingly enough, however, Buangkok Drive is the boundary between Sengkang and Hougang estates. Whereas before, half of PN69 was in Sengkang and the other half was in Hougang estate, PN69 is now entirely in Sengkang. MARUAH has previously called for electoral boundaries to be aligned with URA planning areas. If the boundaries are to be redrawn, a logical spliit would be to assign PN69 to a new Sengkang GRC while PN70 is merged into a Hougang GRC.
Sengkang estate is currently split between three constituencies: Sengkang West SMC, Pasir Ris-Punggol GRC and Punggol East SMC. While the government has traditionally not made major changes to opposition-held constituencies such as Punggol East, and many other HDB estates are also split between different Town Councils, it would make far more sense to simply consolidate Sengkang into a single GRC and to hive off the Hougang portion of Pasir Ris-Punggol into an enlarged Hougang or Aljunied-Hougang GRC. Combining Sengkang West, Sengkang Central (now in Pasir Ris-Punggol) and Punggol East would give a GRC with 43 polling districts – about right for a 5-member GRC. Of course, boundary delineation is not based solely on objective estate management grounds. Government may instead leave Punggol East alone and combine Punggol and Sengkang West and Central into a Punggol-Sengkang GRC instead. If they do create a Sengkang GRC, however, that would leave 6 Pasir Ris-Punggol precincts (PN64-PN68 and PN70) which are actually in Hougang estate, orphaned. Perhaps these should be merged into Aljunied-Hougang together with another 5 precincts presently in Ang Mo Kio GRC (AM16-AM20) but which are part of Hougang estate, in exchange for Punggol East ?
UPDATE 8:00 PM Haha. This post was posted in the wee hours of the morning of 24 July and the Electoral Boundaries Review Committee (EBRC) report was released at 3:00 pm. Looks like my predictive ability can be described as half-full or half-empty.
Coney Island – Coney Island was indeed transferred out of East Coast GRC but not into a new GRC. Instead it was added to the existing Pasir Ris-Punggol GRC
Sengkang – A new boundary was indeed created along Buangkok Drive by hiving off the Hougang portions of Pasir Ris-Punggol. PN69 was retained within Pasir Ris-Punggol while PN70 went to Ang Mo Kio.
Hougang – As predicted, PN70 was transferred out of Pasir Ris-Punggol but not into Hougang-Aljunied. Instead, it was absorbed into Ang Mo Kio GRC together with the portion of Pasir Ris-Punggol south of Buangkok Drive.
Whitley Road – I didn’t get round to writing this up last night, but I did notice that MK03 and MK05 in Moulmein-Kallang GRC were realigned so that the boundary would be along Whitley Road rather than in the middle of the landed housing estate at Chancery Lane. My inference was that this was in preparation for Whitley Road to become a boundary between two constituencies, and this was borne out when Moulmein-Kallang was dissolved and MK03 went to Holland-Bukit Timah while MK04 was added to Tanjong Pagar GRC.
So overall, my predictions were accurate at micro-level but I did not do so well at higher level. My two correct predictions, Coney Island and Whitley Road, are not very consequential. Where I failed was being too idealistic in the North-East region. The PAP presumably recognised that they would face a tough fight in the Punggol/Sengkang/Hougang North area so instead of creating a new GRC for the HDB’s latest showcase estates in the North-East, they bled off the voters into AMK and Pasir Ris-Punggol, both six-member GRCs, to dilute the voting strength of the younger voters in those estates. I completely did not foresee that Sengkang would be split further, into four constituencies, with part of Sengkang going into AMK GRC. At this rate, Ang Mo Kio is becoming the new Marine Parade. Specifically, the area around Hougang Street 51 and 61 was transferred from Pasir Ris-Punggol GRC to Ang Mo Kio GRC. The HDB Blocks near Street 61 have thus moved from Aljunied to Pasir Ris-Punggol to Ang Mo Kio GRC in the last three elections. In addition, one-third of the voters in Sengkang West SMC have been moved from the constituency into Ang Mo Kio GRC.
Filed under: Elections, Electoral Boundaries, General Elections | 1 Comment
- The delimitation process in Singapore is opaque and not subject to public scrutiny. Some boundaries appear to be arbitrary or designed to favour one party. This results in weaker community ties and cynicism towards the political process.
- Maruah urges the government to raise the level of impartiality, equality, representativeness, non-discrimination and transparency of the boundary delimitation process in Singapore
Slides from the press conference are here:
Filed under: Elections, Electoral Boundaries, General Elections, Presidential Election, Singapore | 1 Comment
Map of reported Israeli airstrikes and ground engagements in Gaza, overlaid on map of Singapore. Gaza is even smaller than Singapore, roughly 40km long x 6-12 km wide, in comparison to mainland Singapore’s, 40 km x 20 km. Israel has declared 44% of Gaza off-limits in the present offensive, so 1.8 million Gazans are squeezed into an area of 200 sq km, less than one-third of Singapore. In that light, the 1,000-plus Palestinian casualties, most incurred over the last few days, are hardly surprising. Though I suppose Israel’s defenders would argue that the casualty rate would be even higher if Israel did not follow such strict rules of engagement.
Red areas in the Singapore map represent what the URA calls “special uses” in its Master Plan. What that usually means is military facility. Note the presence of SAF bases immediately next door to Jurong West, Woodlands, Yishun and several other HDB estates.
Filed under: Uncategorized | Leave a Comment
Tags: Gaza, Singapore
The Personal Data Protection Comission (PDPC) has argued that the existing customer exemption was introduced to give consumers the choice of receiving promotional messages and also that other countries such as the UK had similar exemptions. These arguments are red herrings: Even without the exemption, individuals always had the choice of giving consent to receive promotional messages and the UK “soft opt-in” rules for existing customers require that individuals must be given a chance to opt out at the time their data was initially collected.
Had they wanted to, the PDPC could have implemented a “soft opt-in” in Singapore even without an exemption order. Considering that businesses had more than a year to prepare for the implementation of the DNC after the Act was passed, the PDPC could have encouraged businesses to make use of that window to get consent from their customers. Instead, the PDPC created a permanent exemption which inverts the basic premise of Data Protection that individuals have the right to control how their personal information is used. Instead of the default position being that businesses should not use a person’s data without permission, the default has been inverted such that the company has the right to send promotional messages until consent is withdrawn.
Granted, the fact is that most businesses did not prepare in advance and did not get express or implied consent to send marketing messages even to customers with whom they had an on-going relationship. A hard stop once DNC kicked in may have been quite disruptive to many companies. Had a public consultation been held, I could have lived with a time-limited exemption under which businesses would be given a limited time, say one year, to get consent from their existing customers to send marketing messages. This would not be unduly onerous to businesses – If they claim to have an “ongoing relationship”, they should certainly be contacting that customer at least once a year anyway. Unfortunately, there was no public consultation so now we are stuck with a permanent exemption which subverts one of the basic principles of Data Protection.
Filed under: Uncategorized | Leave a Comment
Tags: DNC, Do Not Call, PDPC, Personal Data Protection Comission, soft opt-in
Six MPs have submitted questions for Monday’s Parliament sitting regarding the implementation of the Do Not Call registry. Unfortunately, none of the questions directly address the fact that the government changed the regulations at the last minute without any public consultation. To recap, the government announced in 2011 that it would finally be introducing Data Protection legislation, some 22 years after the government first created a committee to study the issue. A Do Not Call (DNC) registry was to be included in the Personal Data Protection Act (PDPA) and three rounds of public consultation were held before the Act was passed by parliament in 2012. The DNC registry opened for registration on 2 Dec 2013, but one week before the DNC rules were due to come into effect on 2 Jan 2014, the government announced an exemption that would allow businesses to SMS and fax existing customers. Telemarketers cheered but individuals were shocked and dismayed by the sudden weakening of a long-anticipated law that Singaporeans had hoped would protect them from junk calls and messages.
We can argue over whether the exemption is in fact “pragmatic” and “reasonable” or similar to other country’s rules, but the fact is that the government changed the rules at the last minute, without warning and without any public consultation, in stark contrast to the far more open and transparent manner in which the PDPA and DNC rules were originally drafted. Three rounds of public consultation were held, and unless the commenter requested otherwise, all comments were published on the Ministry of Information, Communications and the Arts (MICA), now Ministry of Communications and Information (MCI), website. It was very much the open, transparent, consultative approach to policy making associated with the Our Singapore Conversation (OSC) and which Singaporeans hoped to see more of.
Yet once the rubber hit the road, the government fell back to its old, familiar method of formulating and implementing public policy. The government decided what was best for us behind closed doors and that was that. In other words, it’s the Population White Paper all over again. Just as the government views us as economic digits in calculating its target population for Singapore, the PDPC refers to us as “consumers” rather than as “individuals”. But of course, to be “consumers”, we have to consume and companies have to have a way to sell to us. The PDPC’s repeated claims that the exemption was made in the interests of consumers is at best paternalistic and at worst an attempt to turn black into white, just as they initially claimed that businesses never raised the issue of existing customers until after the close of public consultations. Ironically, one of the members of the PDPC had suggested that a public message board be created to take in ideas, views and comments as part of the National Conversation. In Arun Mahizhnan‘s words, “Such transparency will go a long way to pacify the widespread perception that the government is selective in its hearing and self-serving in its sharing. After decades of careful orchestration of what the public says or hears in public, the completely transparent modus operandi on the part of the government will be refreshing and reassuring.” He goes on to say, “If the government explains its rationale for selecting only certain ideas for further consideration clearly and carefully, the fallout should be manageable.”. While not completely open, the Data Protection public consultations held in 2011-2012 were fairly close to this ideal. In contrast, the process by which the existing customer exemption was created in 2013 was policy-reversal by fait accompli. The PDPC only grudgingly acknowledged there was even a policy reversal at all, let alone give a rationale for making the change. We most certainly were not given any chance to present counter-arguments against the exemption.
We have seen in 2013 two contrasting faces of the PAP. There was the PAP of the White Paper – arrogant, paternalistic, top-down – and the PAP of the OSC – open, consultative, touchy-feely. Much as the DNC exemption is, on the scale of things, a storm in a teacup, we can again see both sides of the government. During the initial public consultations for the Data Protection Act, we saw the open, consultative PAP of the OSC but when the DNC exemption was inserted without prior warning, we saw again the old arrogant, paternalistic, top-down and secretive PAP . So which is the real PAP ? Come 2016, which PAP will be voting for ?
Filed under: Uncategorized | 1 Comment
Tags: DNC, Do Not Call, PDPC, Personal Data Protection Comission, White Paper