STAT 166

• Statistics


  A science, a body of knowledge concerned with the collection, organization, presentation, analysis and interpretation of data
• Statistics


  A set of numerical figures, a collection of facts and figures or processed data
• Use of Statistics


  • Describe the general characteristic of the collection of elements under study called the population
  • Compare different subpopulations
  • Explain a phenomenon that has taken place in the population
  • Predict future phenomena that will take place in the population
  • Describe the relationships of the different characteristics of the elements in the population
  • Study cause-and-effect
• Population


  A collection of all the elements under consideration in any statistical study
• Sample


  A part (or subset) of the population from which information is collected
• Variable


  Characteristic or attribute of the elements in a collection that can assume different values for different elements
• Observation


  Realized value of a variable
• Data


  The collection of observations
• Qualitative Variable


  Have labels or names assigned to their respective categories, assumes values that are not numerical but can be categorized
• Qualitative Variables


  • Sex, marital status
• Quantitative Variable


  Any characteristic that can be measured or counted in numbers, indicates the quantity or amount of a characteristic, can be discrete or continuous

  
• Quantitative Variables


  • Household income, weight (kg)
• Nominal Level of Measurement

  The numbers in the measurement system are used to classify an element into distinct, non-overlapping, and exhaustive categories, categories are of equal importance, arithmetic operations cannot be done
• Nominal Variables


  • Sex (1- male and 2 - female), occupation (farming, laborer, employee)
• Ordinal Level of Measurement


  Deals with qualitative variables, but there is inherent ordering, the difference between categories cannot be measured and has no meaning

  
• Ordinal Variables


  • Satisfaction rating (1-10; 1 being the lowest and 10 being the highest), extent of damage (minimal, moderate, serious), living condition (poor, good, excellent)
• Interval Level of Measurement


  Deals with quantitative variables with differences between two consecutive quantities being constant, but variables have no absolute zero point
• Interval Variables


  • Temperature (°C), IQ
• Ratio Level of Measurement


  Deals with quantitative variables with differences between two consecutive quantities being constant, and variables have an absolute zero point
• Ratio Variables


  • Number of siblings, weight (kg), height (cm), number of household members
• Parameter


  A summary measure describing a specific characteristic of the population
• Statistic


  A summary measure describing a specific characteristic of the sample
• Descriptive Statistics


  Techniques used in organizing, summarizing, and presenting the data collected from either sample or a population

  
• Inferential Statistics


  Techniques used in analyzing the sample data that will lead to generalizations about a population from which the sample came from
• Discreet variable  

  
  

  represent counts; finite or countable number of possible values
• Continuous variables - represent measurable amounts; assures any value in a given interval
• Measurement - the process of determining the value or label of a

  particular variable for a particular element based on

  what has been observed
• Research Process


  A set of activities in which social scientists engage to answer questions, examine ideas, or test theories
• Empirical Research


  A research based on evidence that can be verified by using direct experience
• Statistical Inquiry


  A designed research that provides information needed to solve a research problem
• Steps in Statistical Inquiry

  1. Identify the problem and state the hypothesis

  2. Plan the study

  3. Collect the data

  4. Explore the data

  5. Analyze and interpret the results

  6. Present the results
• Information


  Processed data
• What distinguishes a statistical inquiry from other types of research is the use of data that have been collected and analyzed in answering the research problem
• Observation


  The data are obtained by recording or watching the behavior of an individual or a phenomenon at the time of occurrence
• Experimentation


  There is direct human intervention on the conditions that may affect the values of the variable of interest
• Use of Documented Data


  Researchers can use documented data from previous studies of individuals or private, government and non-government agencies
• Sources of Documented Data

  • The Philippine Statistics Authority
  • Bangko Sentral ng Pilipinas
  • Philippine Atmospheric, Geophysical, and Astronomical Services Administration
  • The Social Weather Station/Pulse Asia
• Registration


  Enumeration and recording of vital statistics
• Registration


  • Registration of birth/death/marriage
  • Voter registration
  • Sales inventory
  • Registration of participants in a program
  • Signing-up to a social media platform
• Survey


  The data are obtained from individuals either by verbal or written communication