More than 99 million Mexicans are called to go to the polls on Sunday, June 2, to participate in the biggest election in the country's history. There are 20,708 public positions at stake, including the presidency and the renewal of the federal Congress.
Mexico's National Electoral Institute (INE) provides two tools for citizens to find out about preliminary results and voting trends on election day.
Voting in the country takes place through the Preliminary Electoral Results Program (PREP) and quick counts, which are not the same thing. Understand how each one works below.
What is PREP?
PREP is a tool that collects, processes and publishes preliminary voting results on election day, according to INE.
The program launches at 8pm local time, a few hours after polling stations close. In this way, PREP begins to produce preliminary results that can be consulted in real time on the Internet through the electoral body's official channels.
In addition to “exit” polls (which are not the same as PREP), the media in Mexico publishes data from this method during their election day coverage.
It is important to note that program results are not official results.
The final count takes place until the Wednesday (05) after election day, explained Claudia Edith Suárez, chief executive secretary of INE, during a press conference in May.
- How it works?
On election day, after the polls close, polling station employees will count the votes and fill out approximately 515,000 tabulation sheets.
According to INE, there are two ways to digitize registration sheets:
Using a mobile application called “PREP casilla”, which allows information from the totalization sheets to be captured from each of the polling stations across the country and transmitted to data collection and transmission centers.
Once received at the collection centers, the totalization sheets are scanned, a double data collection and compatibility check are carried out and finally they are published on the Internet, where citizens can follow the results in real time.
Another form of capture involves the registration sheet being transported within the electoral package, from the polling station to the district council, where it is captured and digitized to go through the same verification and publication process.
“PREP is not an exit poll, nor does it replace the official count of district counts that begin the Wednesday after Election Day,” Suárez said.
“Instead, it provides a preliminary overview based on real data collected at polling stations and is completed by the next day, so its shelf life is 24 hours,” he adds.
The Superior Chamber of the Electoral Court of the Judiciary of the Federation, the highest jurisdictional authority on electoral matters in the country, declares the validity of the presidential election after determining that the elections were conducted in a “free, authentic and democratic” manner.
Furthermore, the body is responsible for resolving any challenge or controversy that may arise in the electoral process.
The quick count
Unlike PREP, quick count is a statistical method that predicts voting trends based on a random sample of polling stations that is also released on the evening of Election Day, according to INE.
- How it works?
The quick count is triggered around 6 p.m. local time, when polling stations close, Alejandro Sosa Durán, executive director of the Federal Register of Voters, told CNN .
The survey begins with the compilation of voting results in the polling stations that were selected for the sample. The data obtained is transmitted by telephone or via a mobile application to be recorded in the quick counts computer system.
Members of the Technical Advisory Committee for Quick Counts (COTECORA) receive the information and make estimates until a definitive trend is known. The COTECORA team delivers the quick count results report to the President of the INE General Council. And then the results are released.
The results of the quick count are neither official nor proof of victory, according to INE.
Measures to ensure reliability
INE carries out at least three simulations before election day in order to “identify and correct” any situation that may arise when these preliminary results systems are put into operation, explained the executive director of the Federal Electoral Registry.
According to Sosa Durán, simulations allow electoral authorities to optimize operational procedures, such as information collection, data transmission times, infrastructure and possible failures of infrastructure equipment, among others.
The INE official also assured that there are plans to reinforce the supply of electricity necessary for the computer equipment used in the collection centers where the results are digitized. Furthermore, they work through a secure network: “the applications have security mechanisms that allow us to identify the person accessing the data processing equipment, and we maintain a record where we know who is entering”.
INE guarantees that PREP offers “immediate transparency” when publishing the results of voting at polling stations.
“We have the support of a technical advisory committee made up of experts in different disciplines – statistics, information technology and security, political science, among others – whose function is to provide continuous technical advice, which is fundamental to providing this solid and safe support the entire process,” said Suárez.
Source: CNN Brasil

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