Stats and Proba

• Statistics - •A branch of mathematics dealing with the collection, organization, presentation, analysis and interpretation of data
• 4 Essential Processes in Statistics: Data Collection, Data Analysis, Data Presentation, Data Interpretation
• Collection of data

  -refers to the gathering of related information
• Presentation of data

  • refers to the systematic way of organizing data
• analysis of data - extracting relevant information from the data at hand
• interpretation of data - drawing of logical statements from the analysed
• POPULATION  is the entirety of the group including all the members that forms a set of data
• SAMPLE contains a few members of the population. Samples were taken to represent the characteristics or traits of the population
• DESCRIPTIVE STATISTICS used to say something or describe a set of information collected. It can also be represented with graphs.
• INFERENTIAL STATISCTICS used to say something a larger group (population) using information collected from a small part of that population (sample)
• PRIMARY DATA

    -refers to the first hand data gathered by the researcher himself. 
• SECONDARY DATA

    -the data that has already been collected through primary sources and made readily available for researchers to use for their own research
• 1.DISCRETE QUANTITATIVE VARIABLE

    - a variable which can assume finite

    - usually measured by counting or enumeration
• 2.CONTINUOUS QUANTITATIVE VARIABLE

    - a variable which can assume infinitely many corresponding to line interval
• 1.DIRECT OR INTERVIEW METHOD

    - person to person encounter between the source of information, the interviewee and the one who gathers information, the interviewer
• 2.INDIRECT OR QUESTIONNAIRE METHOD

    - technique in which questionnaire is used to elicit the information or date needed
• 3.REGISTRATION METHOD  - obtains data from the records of the government agency authorized by law
• 4.OBSERVATION METHOD  - technique in which data particularly those pertaining to the behaviors of individual or group
• 5.EXPERIMENTAL METHOD

    - a system used to gather data from the results of performed series of experiments on some controlled and experimental variables
• 6.SIMULATION

    - a process of conducting experiments to understand the behavior of the system or potential strategies for operators of the system
• 7.PANEL METHOD

    - a method of collecting data repeatedly
• 8.MAIL SURVEY  - sending questionnaires by mail to target respondents with a request to
• 9.PROJECT TECHNIQUES

    - respondents presented ambiguous stimuli for interpretation 
• 10.SOCIOMETRY

    - method of finding, describing and assessing social status, structure and development by measuring acceptance or rejection 
• Probability - The chance that a particular event will occur
• 1.Classical

    - is a simple form of probability that has equal odds of something happening
• 2.FREQUENTIST

    - it defines an event's probability as the limit of its relative frequency in many trials (the long-run probability)
• SUBJECTIVE

    - does not base its probability on quantitative information, is affected by personal beliefs, and contains no formal calculations
• BAYESIAN  -is the process of using probability to try to predict the likelihood of certain events occurring in the future
• Sample Space - is the set of all possible outcomes of a statistical experiment
• events -  a set of outcomes of a random experiment
• INTERSECTION

    - The intersection of events A and B, denoted by A ∩ B, consists of all outcomes that are in both A and B.
• The union of events A and B, denoted by A ∪ B, consists of all outcomes that are in A or in B or in both A and B.
• COMPLIMENT OF SETS

    - If U is a universal set and A be any subset of U then the complement of A is the set of all members of the universal set U which are not the elements of A denoted by A′.
• random variables - - is a variable whose values depend on the outcomes of an experiment; function that maps the outcome of an experiment to real numbers.
• discrete probability distribution - consists of the values a random variable can assume and the corresponding probabilities.
• permutation - Arrangement of things in a definite order or the ordered arrangement of distinguishable objects without allowing repetitions among the objects.
• circular permutation - A special case of permutation where the arrangement of things is in a circular pattern.
• Combination - Selection made from a group of items without regard to their order.