M1 - lesson 3

• Element or Member


  A specific subject or object (for example, a person, firm, item, state, or country) about which the information is collected
• Variable


  A characteristic under study that assumes different values for different elements
• Observation or Measurement


  The value of a variable for an element
• Data Set


  A collection of observations on one or more variables
• Quantitative Variable


  A variable that can be measured numerically
• Discrete Variable


  A variable whose values are countable
• Continuous Variable


  A variable that can assume any numerical value over a certain interval or intervals
• Qualitative or Categorical Variable


  A variable that cannot assume a numerical value but can be classified into two or more non-numeric categories
• Cross-Section Data are data collected on different elements at the same point in time or for the same period of time
• Time-Series Data are data collected on the same element for the same variable at different points in time or for different periods of time
• Population


  All subjects (human or otherwise) that are being studied
• Sample


  A group of subjects selected from a population
• Statistic


  A characteristic or measure obtained by using the data values from a sample
• Parameter


  A characteristic or measure obtained by using all data values for a specific population
• Census


  A survey that includes every member of the population
• Sample Survey


  A survey that includes only a portion of the population
• The purpose of conducting a sample survey is to make decisions about the corresponding population
• Representative Sample


  A sample that represents the characteristics of the population as closely as possible
• Sampling with Replacement


  Each time an element is selected from the population, it is put back before the next selection
• Sampling without Replacement


  The selected element is not replaced in the population
• Data


  are the values (measurements or observations) that the variables can assume.