Math M2

• Data collection - systematic approach to get relevant informations from a variety of sources
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  Collection of data- first step in any statistical work and it is a process of obtaining information
• Primary data- first-hand experience, can be obtained by doing interview, observation, or experimentation
• Interview- direct method of gathering data, it is person-to-person inquiry.
• Interviewee- the person supplying the data.
• Systematic sampling- it is a process of selecting every nth element in the population.
• Stratified sampling- dividing the population into strata or classes.
• Cluster sampling- done in randomly selecting group.
• Non-probability sampling- not every element in a population is given an equal chance of being included in the sample.
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  Convenience sampling- a method in which people are chosen because they are convenient.
• Quota sampling- similar to stratified sampling but the difference is it is not done randomly.
• Purposive sampling- done when a criteria of the study satisfy a particular sample.
• Probability sampling- every element in a given population is given an equal chance of being included in a sample.
• Simple random sampling- can be done by picking names placed inside a bowl or in a computer-generated system.
• Sampling- process of choosing a representative of a population.
• Secondary data- data collected from a source that has already published in any form .
• Questionnaire- indirect method of gathering data, includes written questions to be answered by respondents.
• Observation- makes use of senses in gathering information.
• Census- known as registration.
• Experimentation- process of performing scientific to determine something.