Final answer:
In the theoretical world of statistics, a parameter corresponds to data about an entire population, such as the mean age of all people in a city, while a statistic is derived from a sample of that population. The 50 percent figure from the U.S. federal government survey is a statistic if it's from a sample and a parameter if it's from the entire population of high school seniors.
Step-by-step explanation:
In the theoretical world of statistics, the correct corresponding feature to a statistic such as an average is a parameter. A parameter refers to a numerical characteristic of the entire population. For instance, if we wanted to know the mean age of all people in a city, we would calculate the parameter if we had access to the ages of every person in that city. On the other hand, a statistic is calculated from a sample, which is a subset of the population. For instance, if we only surveyed a group of people from that city, the average age from that group would be a statistic that estimates the parameter.
To answer the student’s question on what would be the corresponding feature to statistic in the theoretical world, if we consider the U.S. federal government survey example where 50 percent of high school seniors plan to attend a four-year college or university, that 50 percent would be classified as a statistic if it represents a sample of the population. However, if that figure represented the entire population of high school seniors, then it would be a parameter.