Lok Sabha Election 2019: News18-IPSOS exit poll shines as the most accurate survey

The News18 exit poll survey conducted by IPSOS India proved to be the most accurate exit poll in 2019 general elections, keeping its brilliant global track record of predicting election results with high level of reliability intact. Here is a comparison of predictions from different pollsters on three key indicators (seat predictions for NDA, UPA and others) and how much each deviated from the actual:

The agency names are sorted as per their accuracy level, that is, the least to maximum total deviation (in the last column). It can clearly be seen that some agencies have deviated as much as three-digit level on these three key indicators. If we go for deeper analysis (like individual party or state specific predictions), the gap between IPSOS and the next best widens further. IPSOS also came out with high accuracy in predicting the NDA vote share as 48.5 percent.The provisional data shared by Elelction Commission also confirms that actual vote share of NDA is 49 percent. The high level of accuracy was maintained by the IPSOS by a detailed and meticulous ‘Planning, Execution and Analysis’ exercise. Planning stage IPSOS took cue of its rich global experience of conducting political polling to ensure nothing is left to chance. Scientific sampling was a crucial building block of success. At first, the parliamentary constituencies (199 in number) were selected using Stratified Random Sampling technique. To select 796 Assembly constituencies within these 199 parliamentary constituencies, IPSOS used Simple Random Sampling. As many as 4,776 polling stations were selected using Systematic Random Sampling. Time-location cluster sampling was done at polling stations level to ensure different demographics and every third (or fifth person in some high traffic PSs) person was approached to avoid group biases. Execution stage All plans were assiduously followed using pure exit poll methodology. Unlike some other agencies, it was not mixed with shortcuts like post-poll, online, telephonic, mobile app etc. Survey was conducted on voting day in all seven phases of polling and only on those days in pre-decided polling stations. This was done to ensure that the voter was in the same frame of mind and not changed by any influence. All interviews were done using tablets. Power banks were provided to each interviewer to ensure no compromise on time-location cluster sampling. The tablets had EVM simulated on it and it was ensured that the voter pressed the button of the simulated model of the EVM without the interviewer’s knowledge. This helped in capturing unbiased response. The fieldwork of the in-house data collection team, which is the largest in the nation, was monitored from four regional control rooms and one national control room. Before accepting or rejecting the data, a team of about 35 quality control executives conducted concurrent quality checks on the interviews. Live monitoring, data on real time basis and GPS-enabled devices had also ensured the quality of field work. Experience of every phase was implemented in the next phase of election to pre-empt likely on-ground challenges and thereby risk assessment and mitigation strategies were planned accordingly. The data was then weighed by age, gender, religion and caste to make the sample representative of each parliamentary constituency. Further, deep dive into the exit poll results with a detailed analysis of voter mood, trends and factors were considered using mathematical models to arrive at vote estimates and seat predictions. The core research team of IPSOS traveled extensively in different parts of the country during these five-six weeks, which helped them in understanding the pulse and underlying issues at different parts. Different possible biases, like Bradley effect (people not sharing honest data due to social/political reasons of embarrassment or fear), were also picked up during these visits and factored in during the analyses stages. IPSOS had done trust surveys between November 2018 and March 2019. These insights gave IPSOS a ready reference to understand the trends and go for the right predictions and re-affirm its position as India’s most accurate exit poll.