Math

• Population 


  Repairs to the entire group chat is under study or investigation
• Sample


  Is a subset taken from a population?
• Random sampling 


  It is a selection of elements derived from a population on n which is the subject of the investigation or experiment
• Simple random sampling 


  The most basic random song playing were in each element in the population has an equal probability of being selected
• Systematic random sampling 


  It is a random sampling that uses a list of all the elements are being selected in interval call sample interval
• Stratified random sampling 


  It is a random sampling where in the population is divided into different strata or division
• Cluster random sampling 


  It is a random sampling where in population is divided in to a cluster or groups then the Cluster are randomly selected
• Non random sampling 


  Is use when the sample is not proportion of the population and when there is no system in selecting a sample
• Accidental sampling 


  Only those whom the researchers meets by chance are included in the same playing when using this technique
• Quota sampling 


  Includes a specified number of person off certain types to be taken as sample
• Convenient sampling


  Most convenient and fastest sampling technique that make use of the telephone mobile phone or the internet
• Purposive sampling 


  Use in very small sizes
• Mean


  Also known as the average is calculated by dividing the sum of the observation by the total number of observation
• Variance


  Is Define as the average of the square deviation from the mean
• Standard deviation 


  The square root of the variance