What is Population? Sample?
In statistics, researchers, and educators
commonly use the terms population and sample (Alferez & Duro, 2006). The population is often too large for us to examine
each of its members.
The population is the entire collection of all elements/experimental units under consideration in a statistical inquiry or to be studied. Sample a part of the population. If the sample is to provide information about the entire population, it must be representative of that group in some way. In actuality, unless a sample is picked at random, it cannot be expected to be representative of a population. This is because any nonrandom rule for selecting a sample will almost always produce one that is skewed toward some data values over others.
For example, if we wish to determine the average income of households in Zamboanga del Norte, then the population of interest is the collection of all households in Zamboanga del Norte. However due to some constraints, the budget, the time, the manpower for instance, and then we would have to redefine the interest. This time we can delimit the scope of the study we utilized sampling size to include only the collection of all households in Dapitan and Dipolog City, considering this is done thru sampling techniques.
Parameter refers to any numerical value describing a characteristic of a population and is usually denoted by some Greek letters such as population standard deviation, σ and population mean, μ.
While the term statistic is a numerical measurement describing some characteristics of a sample. The symbols x and s are statistics which is unbiased of the parameter μ and σ.
Two Major Areas of
Statistics
Descriptive Statistics
Is
concerned with the methods for collecting, organizing, and describing a set of
data so as to yield meaningful information (Walpole, 2000). Construction of tables, charts,
and graphs and the computation of descriptive statistical measures also
fall in this area.
Inferential Statistics
Inferential Statistics is also called Inductive
Statistics or Statistical Inference. Comprises those procedures
for drawing inferences or making generalizations about characteristics of a
population-based on partial and incomplete information obtained sample data to
infer to populations.
SEE YOU ON THE NEXT TOPIC:
Introduction to Statistics
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