Final answer:
In statistics, a 'population' refers to the complete set of items or individuals sharing common characteristics that are studied, which can be animate or inanimate objects, not just humans. Demography is the study of population in terms of size, density, and birth and death rates, to understand how groups change over time. Representative sampling is fundamental to obtaining valid population parameters from sample statistics.
Step-by-step explanation:
What is a Statistical Population?
In statistics, the term population refers to the complete set of items or individuals that have one or more characteristics in common that are of interest for some question or experiment. This can mean all people living in a country, all the trees in a forest, or every penguin in a colony. The statistical definition of population encompasses not only humans but any category of similar items or beings. For instance, a population of butterflies in a meadow, or a population of cars produced by a factory could be the focus of a statistical study. In every case, the population is the entirety of subjects to be studied.
Demography is the statistical study of populations, where populations are examined in terms of their size, density, dispersion, birth rates, and death rates. Each characteristic can impact how populations function and adapt to changes in the environment. For example, knowing the population size of a certain fish species helps scientists determine the risk of extinction or the impact on ecosystems. The concept is essential in both ecology and statistical research because it sets the stage for studying the dynamics of how groups change over time.
When analyzing a population in statistics, it's also crucial to have a representative sample that accurately reflects the characteristics of the population. This ensures the validity of inferences made about the population based on the sample. The ultimate goal is to understand the population parameter, which is a summary measure of the population that a sample statistic is trying to estimate.