POLLS

Methodology

Approved by: William-Jose Velez
Editor in Chief
Last updated: 5/22/2016

Introduction

The Pasquines Polls consists of completed interviews among adults residents of Puerto Rico using a sample selected from our opt-in online panel to match the demographics and other characteristics of the adult population in the United States territory. These surveys are conducted in English and Spanish, simultaneously, meaning the questions and options are offered in both languages at the same time.

 

Sample Design

Our methodology differs from a traditional telephone poll in a number of ways. Typically, telephone polls work by randomly sampling working numbers (or numbers sampled from an official list of registered voters). For polls conducted on the internet, there is no comparable mechanism for drawing a random sample of all email addresses or other online accounts. Pasquines approaches this problem by recruiting a large panel of internet users who have agreed to participate in online surveys. This panel is itself not representative of the Puerto Rico population, but samples are drawn from that panel to match available demographic and voting data. This is a purposive, rather than random, method of selection, designed to eliminate selection bias and non-coverage of the target population in the panel from which respondents were drawn.

Because of limited resource, our surveys are non probability sample based polls. Our aim is to obtain a random, representative sample of the voting population in Puerto Rico. To achieve this, we correct and weigh responses according to demographic and voting history information. The target population for the survey is adults aged 18 or higher residing in Puerto Rico. All panelists are, by necessity, at least occasional internet users.

All respondents are “cookied” to discourage attempts by persons to take the survey multiple times.

 

Sample Selection and Weighting

Our panels are recruited in three ways:

(1) Through e-mails to people from our e-mail list inviting them to join the panel.

(2) Through advertising, principally using Facebook but also through social media posts on Twitter, LinkedIn and Google+,, in which ads are placed against a wide variety of political keywords—eg, status, statehood.

Data is weighted using age, gender, and educational level. We also track and weight by respondent’s reported vote in the 2012 election. The weighting for this is based on the actual result.

 

Interviewing Procedures

When joining the panel, respondents supply a great variety of background demographic and other information.

Afterwards, depending on their party affiliation, they are asked questions on specific primary races, and then on general election contests. We have also included favorability questions on major local and national candidates and officials.

Respondents are then invited to sign up on our subscriber list to receive future poll invitations.

 

Margins of Error

Many interpret the “margin of error,” commonly reported for public opinion polls, as accounting for all potential errors from a survey. It does not. There are many non-sampling errors, common to all surveys, that can include effects due to question wording and misreporting by respondents. In a telephone survey, which begins with a random sample of phone numbers, such errors can occur due to those not covered by the sample, those who cannot be reached and those who do not respond to the survey. With Pasquines’ sampling methodology, errors can occur due to a failure to fully correct for the non-representative nature of the online panel (or, more specifically, due to variables not included among the matching and weighting variables).