IHP’s Sri Lanka Opinion Tracker Survey (SLOTS) MRP provisional estimates of Presidential Election voting intent in all adults in June 2024 show that support for SJB leader Sajith Premadasa increased to 43% (+4) but decreased for NPP/JVP leader AK Dissanayake to 30% (-6) compared to May. Support for Pres. Ranil Wickremesinghe increased to 20% (+3) whilst a generic SLPP candidate runs at 7% (-1). However, the June estimates were associated with a substantial increase in model uncertainty, so the two leading candidates remain within the margin of error.

These estimates use the IHP SLOTS Multilevel Regression and Poststratification (MRP) model (01/2024 revision). This update is for all adults and uses data from 18,213 interviews conducted from Oct. 2021 to 21 Jul. 2024, including 446 interviews during June 2024. 100 bootstraps were run to capture model uncertainty. Margins of error are assessed as 1–11% for June. The margins of error for June estimates are substantially higher than the previous months, which appears to reflect increased volatility in voter preferences, so the two leading candidates remain neck and neck. IHP is planning to expand its interview numbers in coming weeks and hopes that the next MRP update will provide more clarity on current trends. 

IHP’s SLOTS MRP methodology first estimates the relationship between a wide variety of characteristics about respondents and their opinions – in this case, ‘If there was a Presidential Election today, who would you vote for?’– in a multilevel statistical model that also smooths month to month changes. It then uses a large data file calibrated to the national population to predict voting intent in each month since Oct. 2021, based on what the multilevel model indicates about their probability of voting for various parties (‘post-stratification’) at each point in time. The multilevel model was estimated 100 times to reflect underlying uncertainties in the model and to obtain margins of error. The voting intent results for previous months have changed in this update as more data were collected after the last release and these changes are within the margin of error.

About IHP

IHP is an independent, non-partisan research centre based in Colombo, Sri Lanka. The SLOTS lead investigator is Dr Ravi Rannan-Eliya of IHP, who has trained in public opinion polling at Harvard University and has conducted numerous surveys over three decades. 

Methodology

SLOTS combines interviews from a national sample of adults (ages 18 and over) reached by random digit dialling of mobile numbers, and others coming from a national panel of respondents who were previously recruited through random selection. IHP estimates voting intent using an adaptation of Multilevel Regression and Post-Stratification (MRP), with multiple imputation to account for uncertainties in its modelling, exploiting data from all SLOTS interviews to estimate voting in a particular month. 

The June 2024 MRP estimates are based on 18,213 interviews conducted from 1 October 2021–21 July 2024, including 446 interviews conducted in June 2024. The margin of error is assessed as 7.0–11.5% for AK Dissanayake, Sajith Premadasa and 3.5% for Ranil Wickremesinghe and the other potential candidate. All estimates are adjusted to ensure the sample matches the national population with respect to age, sex, ethnicity, socioeconomic status, education, geographical location, and voting in the 2019 Presidential and 2020 General Elections.

Funding

The SLOTS survey has previously been funded by the Neelan Tiruchelvam Trust, the UK National Institute for Health and Care Research (NIHR), The Asia Foundation in Sri Lanka, and others. Current fieldwork is financed by the IHP Public Interest Research Fund and others. The sponsors play no role in the study design, analysis, or interpretation of findings. Furthermore, the survey findings do not necessarily reflect the views or positions of past and present funders. Interested parties can contact IHP for more detailed data and results.