Question

Define what are the four principles of Statistics when collecting data values?

What is the main difference between Statistics and Statistic? Please explain!

What are the main differences between sample and population? Explain with an example to support your answers!

Answer 1

1. Four principles of Statistics when collecting data values are:

Relevance: the collected data should be relevant to the activity or phenomenon you intend to analyse and study.

Simplicity: the collected data should be simple in concept and easy to measure.

Accuracy: the collected data can accurately describe the activity, phenomenon, topic or issue you are studying.

Clarity: the collected data should be clear, unambiguous, easy to interpret and easy to understand.

2. Statistic refers to a “descriptive measure performed over a sample to estimate Population Parameter”. It is basically a function of sample values. For example the sample mean is an statistic for the population mean μ.

Statistics on the other hand is a very broad subject, with applications in a vast number of different fields. In generally one can say that statistics is the methodology for collecting, analyzing, interpreting and drawing conclusions from information.

3. Population is the collection of all individuals or items under consideration in a statistical study

Examples

• The population of all workers working in a factory.
• The population of cars produced by a particular company.
• The population of students in a town.
• The population of voters in India.

Sample is that part of the population from which information is collected.

Examples

• The group of workers of all workers working in a factory.
• The bunch of cars from all cars produced by a particular company.
• The fraction of voters from each state in India.

The difference between population and sample is:

• The population consists of each and every element of the entire group. On the other hand, only a handful of items of the population is included in a sample.
• The characteristic of population based on all units is called parameter while the measure of sample observation is called statistic.
• When information is collected from all units of population, the process is known as census or complete enumeration. Conversely, the sample survey is conducted to gather information from the sample using sampling method.
• With population, the focus is to identify the characteristics of the elements whereas in the case of the sample the focus is made on making the inferences about the characteristics of the population, from which the sample came from.