This is considered a sample survey. A population is the entire group of people that is being studied, whereas a sample is a subset of that population that is studied in order to predict values for the entire population. For example, a population could be all people ages 18-25, whereas a sample would be a group of people in this age group who were selected to fill out a survey. In this case, 1,000 people are selected from the general population to survey. This is, therefore, a sample survey, not a population survey.