module 2

• POPULATION

  • Is a collection of all entities, elements, objects, things, or individuals.
  • The number of observation in the population is known to be the population size denoted by N.
• SAMPLE

  • Is a subset, a part or a small portion of a population.
  • It could also define as subgroup or a representative of the universe.
  • It is used to represent the characteristics or traits of a population.
  • The number of observations in the sample is known as the sample size denoted by n.
• SAMPLING FRAME

  • Is a list of all elements or individuals in a population.
• CENSUS

  • Is a process of gathering information facts or figures from the population.

   
• SURVEY

  • Is a process of gathering information facts or figures from the sample.
• DATA

  • Is a characteristic or attribute of persons or objects which can assume different values.
  • These are collection of facts, figures or pieces of information.
• PARAMETER

  • Is any numerical value describing a characteristic of the population.
  • Ex. Mean, Median, Mode.
  • It is usually referred to as the true or actual value.
• STATISTIC OR ESTIMATE

  • Refers to any numerical value describing characteristics of a sample
• BASIC STATISTICAL CONCEPTS

  POPULATION

  SAMPLE

  SAMPLING FRAME

  CENSUS

  SURVEY

  DATA

  PARAMETER

  STATISTIC OR ESTIMATE
• DATA are individual pieces of actual information recorded and used for the purpose of analysis. It is the raw information from which statistics are created. 
• PRIMARY DATA

  • These are set of information gathered directly from the source which are based from first-hand experience.

   
• INTERVIEW METHOD

  •        It is a person-to-person exchange of information between the interviewer and the interviewee.

  •        It provides more consistent and more precise information.
• Questionnaire Method

  • It is applied when written response are given to prepared questions.
• REGISTRATION METHOD

  • It is done when information is reported immediately after its occurrence.
• Observation Method

  • It is where the behavior of persons or organizations are observed and recorded by the researcher
• Experiment Method

  • It is used to determine the cause-and-effect relationship of a phenomenon under controlled conditions as in scientific research.
• PRIMARY DATA

  INTERVIEW METHOD

  QUESTIONNAIRE METHOD

  REGISTRATION METHOD

  OBSERVATION METHOD

  EXPERIMENT METHOD
• Secondary Data

  • These are set of information based on existing records.
  • Information which are taken from published materials or data gathered by other individuals or agencies.
  • These are data which are transcribed from original sources.
  • It can be collected from journals, magazines, books, newspapers, and television, internet, radio, private and government agencies.

   
• Qualitative Data

  • Data or information which can assume values that manifest the concepts of attributes.
  • They represent differences in quality character or kind, sometimes called categorical data.

   

  • Information falling in this category cannot be subjected to meaningful arithmetic.
• Quantitative Data

  • Data or information that is numerical in nature.
  • These are obtained from counting and measuring.
  • They represent differences in quantity or amount.
• Discrete Quantitative

  • Data is one that can assume a finite number of values
  • The values are obtained through counting.

  Continuous Quantitative

  • Data is one that can assume infinite values within a specified interval.
  • The values are obtained through measuring
• Measurement – is the process of assigning values to observations in such a way that the numbers are amenable to analysis by manipulation or preparation according to certain rules.  
• Nominal Level

  • Used when one wants to distinguish one object to another for identification purposes.
  • Characteristics of the data show equity among them.
  • The numbers or other symbols are used as code simply to classify objects, persons or characteristics into certain categories or classes.
• Ordinal Level

  • Data are arranged in some specified order or rank
  • The numbers become meaningful because they reveal whether one class or category is more or less than the other.

   

   

   
• Interval Level

  • Has all the properties of the ordinal level and in addition, the magnitude or distance between any two numbers is of known size.
  • There is no natural or meaningful zero, although for convenience a zero points maybe arbitrarily assigned.

   
• Ratio Level

  • Is an interval level with meaningful zero.
  • Members indicate the actual amount of the characteristics being  measured.

   
• LEVELS OF MEASUREMENT

  NOMINAL

  ORDINAL

  INTERVAL

  RATIO
• Sampling techniques are procedures used to determine the individuals or members of the sample. These are also used to answer the question concerning who will be included in the sample. As a rule, a sample should be obtained in a way that reflects the particular characteristics of the population being sampled.

   
• SIMPLE RANDOM SAMPLING

  • It is a method of selecting n units out of the N units in the population
  • Every distinct element has nonzero chance of being drawn.
  • Can be used if the elements in the population have similar characteristics.
  • Lottery method (fishbowl method, chips of paper, raffle draw method) and the use of table of random numbers.
• Stratified Random Sampling

  • The population is first divided into subgroups of strata-based on homogeneity-in order to avoid the possibility of drawing samples whose members come only from one stratum
  • Then select simple random samples of size n from each subgroup using the  proportional allocation  
• Systematic Sampling

  • This method involves a system in selecting every kth element of a series representing the population.
  • The formula in getting kth element is given by k=.
• Cluster Sampling

  • It selects a sample containing either all, or a random selection, of the elements from clusters that have themselves been selected from population.
  • Also called Area Sampling
• SAMPLING TECHNIQUES

  SIMPLE RANDOM SAMPLING

  STRATIFIED RANDOM SAMPLING

  SYSTEMATIC SAMPLING

  CLUSTER SAMPLING
•  Presentation of Data - refers to the organization of data into tables, graphs or charts, so that logical and statistical conclusions can be derived from the collected measurements.  
• Textual presentation of data or narrative form.

  • This involves enumerating the important characteristics, giving emphasis on significant figures and identifying important features of the data.
• Tabular presentation of data.

  • Data are first organized into classes/categories by rows and/or by columns and pieces of information are entered in the cells of the table.
• PRESENTATION OF DATA

  TEXTUAL

  TABULAR

  GRAPHICAL
• Basic parts of a statistical table:

  1.    Table heading- includes table number and title.

  2.    Body- main part of the table containing the information or figures presented.

  3.    Stubs/classes- these are the classification of categories describing the data and are usually found at the left side of the table.

  4.    Caption- designations or identifications of the information contained in a column usually found at the top of the column.

   
• The Frequency Distribution Table (FDT)

  • A statistical table showing the frequency or number of observation contained in each of the defined classes or categories.

   

  qualitative frequency distribution table is a tabular presentation wherein the data are grouped according to some qualitative characteristics.

  quantitative frequency distribution table is a tabular presentation wherein the data are grouped according to some numerical characteristics.
• RANGE FORMULA

  • R = HIGHEST VALUE-LOWEST VALUE