Sample

A sample is a subset of population For example, a truckload of potatoes is arriving from New Brunswick to a potato chip manufacturer. All the potatoes in the truck are taken to represent a population and since every single potato can not be laboratory-tested a sample of potatoes representing the population is chosen. If the sample passes the test the population of potatotes is accepted and paid for.

The context of a study is usually pretty clear but don't forget to ask if someone is giving you sample-based data or population-based data. Also, if it is sample-based data what was the basis and methodology for determining the sample.

The object of this first course in statistics is to involve ourselves with how professionals communicate and explain themselves in terms of probability and statistics

It is no longer sufficient to say that this medical treatment is better than the one before based on only brief case history. New drugs also must be properly tested and analyzed in at least three rounds of human trials. These trials are closely scrutinized and the statistical methods used to collect an analyze the numerical results are carefully chosen.

Today, even in the grade schools they are getting children aware to data collection and data display. The basics of how to read a Bar Chart and a Pie Chart is certainly covered before college. We have some basic concepts to review.

Statistics has some important definitions

Population

A population is the complete and entire collection of elements (such as manufactured products, people, measurements) to be studied.

For example, one might deal with the population of all automobiles on the road of Canada.

Simple Random Sample (SRS)

SRS of size n is a sample of size n units chosen in such a way that every collection of n units from the sampling frame has the same chance of being chosen.

An SRS when properly administered is a common and approved procedure for determining a sample. Due to time and money restrictions, an entire population can not be analyzed. Figure out a sample routine or format that covers a portion of the population.

Even chartered accountants do not have the time to check all the monetary transactions of a large company.The procedure then is to define, beforehand, a system of obtaining simple random samples in all the monetary transaction areas.