In the Sri Lanka Opinion Tracker Survey (SLOTS) polling for July 2023, support amongst likely voters for the major parties remained with little change from the previous month. The SJB and NPP/JVP remain ahead with 24% and 23% each, and the SLPP and UNP on 9% and 8% each. But the largest share–30% of likely voters–remained unwilling to name any party.
The latest MRP estimates using the SLOTS polling data confirms a general decline in support for the NPP/JVP and SJB since early 2023, with modest increases in support for the UNP and SLPP, which both remain behind. They also confirm a large increase in voters who say they will vote for another party but are unwilling or unable to say which.
Dr. Rannan-Eliya, IHP Executive Director, commented: “These latest results again confirm that a large share of the electorate is increasingly uncertain who to support. This would suggest that none of the major parties have succeeded in making a convincing case to the public, and it implies that there is potential for big changes in support in coming months.”
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.
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 July 2023 MRP estimates are based on 466 interviews conducted in July 2023, and 12,269 interviews conducted overall from 1 October 2021–13 August 2023, with a margin of error assessed as 3–5% for the NPP/JVP, SJB, UNP and SLFP, and 1–3% for the other parties. As the May update uses a more recent data set than the previous update, there are small changes in estimates of voting shares for previous months. A total of 62 stochastic simulations were used in the modelling to estimate margins of error.
MRP is a method that is increasingly used by polling firms in other countries to leverage small samples, most notably by YouGov which used it to forecast results of the UK Brexit Referendum and recent UK general elections. 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.
The SLOTS has 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, but the sponsors play no role in the study design, analysis, or interpretation of findings. Interested parties can contact IHP for more detailed data and results.
Date: 21 August 2023
Time: 12:01 AM Sri Lanka Time
FOR FURTHER INFORMATION CONTACT
Email: dalreen ‘at’ ihp.lk
TO CONTACT LEAD INVESTIGATOR
Dr. Ravi Rannan-Eliya
Email: ravi ‘at’ ihp.lk Twitter: @ravirannaneliya