FURTHER NOTES

• • Parameter: A numerical value that summarizes a characteristic of the entire population. Parameters are what we're truly interested in, but often we can't measure them directly. So, we use statistics from samples to estimate the corresponding population parameters
• • Statistic: A numerical value that summarizes the data from a sample. Common statistics include mean, median, mode, standard deviation, etc. We use statistics to describe and understand the important features of the sample data.
• • Data: The actual collected information about the variables we're interested in. This data can come from surveys, experiments, measurements, or any source that gives us values for our variables. Data can be numerical (like heights) or categorical (like hair color).
• • Sample: A smaller subset of the population that is chosen to represent the bigger group. We use samples because studying the entire population can be expensive, time-consuming, or even impossible. The quality of our conclusions depends on how well the sample reflects the population.
• • Population: The entire collection of individuals or items we're interested in studying. It could be all the people in a country, all the trees in a forest, or all the customers of a store. In an ideal world, we'd love to analyze the entire population, but that's not always feasible.
• • Variable: A characteristic or attribute that can take on different values for members of a group. For example, height, weight, hair color, or test scores can all be variables.