Population in Statistics: The people about whom investigator is collecting data are a part of his enquiry's population. For example, if we wish to conduct a survey on usage of baby products, then mothers who have a baby in the age group of 0-5 are a part of our population. Similarly, if a teacher wants to know average height of his class, then students in his class constitute her population. It is also called universe in statistics.
Population in Economics: In economics, population refers to the number of persons living in a particular area. It cannot be called universe in economics.