lesson 1

• Statistics


  A branch of science that deals with studies involving collection, presentation, analysis, interpretation, and drawing conclusions from the data
• General purpose of Statistics

  • Research can see what happened in the research study and communicate the results to others
  • Help researcher to answer questions that initiated the research
  • Helps to determine exactly what general conclusions are justified from the specific results
• Statistics


  • Consists of the collection, organization, presentation and analysis of data
  • Consist the higher degree of analysis, interpretation, and inferences
• Two main branches of Statistics

  • Descriptive Statistics
  • Inferential Statistics
• Hypothesis Testing


  An area of inferential statistics, a decision making procedure to find out whether there is a significant differences between a claim about a population and another information obtained about the said population
• Data


  Any pieces of information useful to the researcher
• Two classifications of Data

  • Quantitative
  • Qualitative
• Variable


  A characteristic of a population or sample which make one different from the other
• Population


  A large collection of objects, persons, or things
• Sample


  A part of a population that has the same characteristics of the given population
• Four classifications of Variables

  • Continuous Variable
  • Discrete Variable
  • Independent Variable
  • Dependent Variable
• Parameter


  A value or measure obtained from a population
• Statistic


  A value or measure obtained from a sample
• Four types of Scales

  • Nominal
  • Ordinal
  • Interval
  • Ratio
• Summation Notation (Σ)


  The most commonly used notation in statistics, which reads "the sum of" or "the summation of"
• Operations in statistics: 1) Calculations in parentheses first, 2) Squaring/exponents second, 3) Multiplication/division third, 4) Summation using Σ next, 5) Addition/subtraction last
• The formula for the sum of an arithmetic sequence is Sn = n(a + l)/2, where n is the number of terms, a is the first term, and l is the last term
• Interval

  this property allows one to make statements of equality of intervals.
• ratio

  this property permits making statements of equality of ratios.
• ordinal

  this variable refers to a property whereby members of a group are ranked.
• nominal

  this property allows one to make statement of similarities or differences. This scale distinguishes one object from another object for identifying purposes only.
• dependent variable

  it is the value affected by change in other factors and is called the criterion variable
• continuous variable

  is one which can assume all values between any two specific values or intervals.
• discrete variable

  assumes values that can be counted and their values are represented by counting numbers only
• independent variable

  its changes caused other variables to change in value and is called the predictor variable