Chapter A and Chapter B (Modules 1-2)

• Statistics


  • In singular sense - a discipline, a body of knowledge (science) that deals with methods of COPAID: Collection, Presentation, Organization, Analysis, Interpretation of data
  • In plural sense - numbers, set of numerical figures
• Statistics


  • Population count
  • Vital statistics (birth rate, mortality rate, etc.)
  • Crime rate per province
  • The average daily hour spent on social media
  • Percentage of Filipinos who are in favor of "same-sex marriage"
• Uses of Statistics


  • Describe the general characteristics of 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 relationship between the different characteristics of the elements in the population
  • Study cause-and-effect
  • A useful tool in decision making

  
• 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


  A characteristic or an 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
• Types of Variables


  • Qualitative variable (have labels or names assigned to their respective categories)
  • Quantitative variable (any characteristics that can be measured or counted in numbers)
• Levels of Measurement


  • Nominal (classification into distinct, non-overlapping, and exhaustive categories)
  • Ordinal (classification into distinct categories with ordering)
  • Interval (classification into distinct categories with fixed unit of measurement and no true zero)
  • Ratio (classification into distinct categories with fixed unit of measurement and true zero)
• The level of measurement is one of the considerations in choosing the appropriate statistical tool to analyze the data
• Parameter


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


  A summary measure describing a specific characteristic of a sample
• Major Areas in Statistics

  • Descriptive Statistics (organizing, summarizing, and presenting data)
  • Inferential Statistics (analyzing sample data to make generalizations about a population)
• The Research Process


  • Identify the problem and state the hypothesis
  • Plan the study
  • Collect the data
  • Explore the data
  • Analyze and interpret results
  • Present the results
• Empirical Research


  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
• Methods of Collecting Data

  • Observation
  • Experimentation
  • Use of Documented Data
  • Registration
• Direct human intervention


  • In the conditions that may affect the values of the variable of interest
• Goal of an experiment

  To isolate the effect(s) of a treatment or intervention on the variable of interest
• Medical technologists


  • Assigned a new brand of vitamins to a set of toddlers while another set was given the already existing brand to compare their effect on the growth of toddlers
• Documented data


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

  • 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
• Examples of registration


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


  Data obtained from individuals either by verbal or written communication

  
• Methods of conducting a survey

  • Personal Interviews
  • Telephone Interviews
  • Mailed Questionnaires
  • Online Surveys
  • Focused group discussions
• Examples of surveys


  • A manufacturing company would interview shoppers on their favorite brand of coffee
  • A study is conducted to study the vulnerability of a community to weather-related hazards. Researchers collected data on the adaptive capacity, sensitivity, and exposure of that community to specific hazards and obtained the community's vulnerability index. They interviewed the residents in the community personally in gathering some information on adaptive capacity and sensitivity. They also use weather data from PAGASA to capture the exposure of the community to particular hazards
• Primary data


  Data acquired directly from the source
• Secondary data


  Data not acquired directly from the source
• Personal interview


  Interviewers personally ask the questions to the respondents and record the answers of the respondents on the questionnaire
• Telephone interview


  The interviewers ask the questions to the respondents through telephone
• Self-administered questionnaires


  The respondents fill up the questionnaire themselves without any assistance from an interviewer
• Online surveys


  The respondent read the questions and sends his responses via the internet or electronic mail (e-mail)
• Mailed questionnaire


  A set of questions mailed to the respondent
• Focused group discussion


  A moderator follows a focus group discussion guide to direct a freewheeling discussion among a small group of people
• Nature of questions, response rates, resources, time, and population are some factors influencing the choice of method in conducting a survey

  
• Mixed collection methods can be done but caution regarding the "mode effect" is necessary
• Census


  When data come from asking every unit in the population
• Sample survey


  When data come from asking a subset of people from a well-defined population