INTRODUCTION%20TO%20STATISTICS

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Topic INTRODUCTION TO STATISTICS
UNIVERSITY OF VETERINARY AND ANIMAL
SCIENCES LAHORE
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INTRODUCTION TO STATISTICS

• Definition
• Statistics is a branch of science, in which we
• Collect
• Observed
• Analyze
• Interpret
• Numerical facts and figures.

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INTRODUCTION TO STATISTICS

• Collect
• Observed

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INTRODUCTION TO STATISTICS

• Analyze
• Interpret

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INTRODUCTION TO STATISTICS

• Statistics is also defined as, it is a science of
  collecting data, processing, organizing and
  interpreting also taking more effective decisions
  on the basis of sample information.
• There are two categories of statistics
• Descriptive Statistics
• Inferential Statistics
• Descriptive statistics is that in which we
  describe the characteristics of population like
  mean, median, standard deviation etc.
• Inferential statistics is that in which we draw
  influence on the basis of sample information
  about the population that is called inferential
  statistics (inference statistical results).

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INTRODUCTION TO STATISTICS
Population Total area under discussion is called
population. The number of observations in a
finite population is called size of the
population and is denoted by N.
Sample An enough and representative part of
population is called sample. The number of
observations in a sample is called size of the
sample and is denoted by n.
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INTRODUCTION TO STATISTICS

• Functions of Statistics
• Statistics has the following major
  functions(uses).
• Statistics helps in collecting and presenting
  data in a systematic and meaningful form i.e.,
  summarizes the larger set of data into an easily
  understand form. e.g., there is a lot of students
  in a particular college does not give an exact
  information as the statement that 480 students
  studying in the college i.e., numerical facts
  give more precise information than facts
  expressed in general terms.
• Statistics facilitates comparisons of data e.g,
  the price indices of a given year easily compare
  with the price indices of previous years.

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INTRODUCTION TO STATISTICS

• Statistics assists in highlighting the important
  features of data and studied relationships among
  different facts
• Statistics helps in prediction or forecasting.
• Statistics help in formulations of suitable
  policies also sound and effective planning in any
  field of inquiry.
• Statistics helps in formulating and testing of
  hypothesis through observed data.

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INTRODUCTION TO STATISTICS

• Importance of Statistics in different fields
• State Management.
• ( Budget, Unemployment, Census etc)
• Pure Science.
• Mathematical Science.
• Psychology, Education and Sociology.
• Business.

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INTRODUCTION TO STATISTICS

• Banks.
• Insurance Companies.
• Economic Economic Development Companies.
• Agriculture.
• Research.

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INTRODUCTION TO STATISTICS

• There are two types of population
• Finite population
• Infinite population
• Population which consists of countable or fixed
  number of values is called finite population.
  Examples?
• whereas population which consists of infinite
  number of values is called infinite population.
  Examples?

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INTRODUCTION TO STATISTICS
Parameter All numerical values calculated from
population is called parameter. And all these
values are denoted by Greek letters. e.g mean and
standard deviation are denoted by µ and s
respectively
Statistic All numerical values calculated from
sample is called statistic. And all these values
are denoted by small letters. e.g mean and
standard deviation are denoted by ? and s
respectively. If we study the total population of
fish in pond which is 100 then it is called as
parameter but if we study specific (20 fish) then
it is called as statistic.
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INTRODUCTION TO STATISTICS

• Variable
• The characteristics which varies from individual
  to individual is called variable e.g. height
  variable, blood pressure level etc.
• Types of variable
• Quantitative
• Qualitative
• A variable which can be measureable numerically
  is called quantitative whereas a variable which
  cannot be measured numerically only can be
  described is called qualitative e.g. marital
  status of man.

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INTRODUCTION TO STATISTICS

• Constant
• The characteristic which does not change is
  called constant.
• Examples?
• Data
• The information collect from the respondent is
  called data.
• Types of data
• Primary data
• Secondary data
• Primary data
• A collection of data at initial stage without
  using statistical tool is called as primary data.
  Examples?

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INTRODUCTION TO STATISTICS

• Sources of Primary Data
• Personal Investigation
• Through Investigators
• Through Local Sources
• Through Telephone
• Through Internet
• Through Questionnaire
• Secondary data
• It is an organized or compact form of data. It is
  obtained from any organizations, institutions,
  governments and semi-governments etc. The primary
  data converted into secondary data after applying
  some statistical tools. Examples?

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INTRODUCTION TO STATISTICS

• Sources of Secondary Data
• Government Organizations
• Semi-government Organizations
• Teaching and Research Organizations
• Research Journals and Newspapers

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INTRODUCTION TO STATISTICS

• Scales of Measurement
• Measurement Measurement refer to Assigning of
  number to observations or objects.
• Scaling Scaling is a process of measuring.
• Four Scales of Measurements
• Nominal Scale
• Ordinal Scale
• Interval Scale
• Ratio Scale

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INTRODUCTION TO STATISTICS
Nominal Scale (Weakest form of
measurement) The classification or grouping of
the observations into mutually exclusive
qualitative categories or classes is said to
constitute a nominal scale. e.g. Sex , Race,
Religion, Country Rainfall may be classified as
Heavy, Moderate, Light Ordinal Scale (When
numbers are allocated in some order) It includes
the characteristics of nominal scale and in
addition has a property of ordering or ranking of
measurements. Attitude scale
Strongly agree, agree, disagree Social scale
Upper, middle, lower
Performance of players Excellent, good, fair,
poor
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INTRODUCTION TO STATISTICS
Interval Scale It has separate categories, like
nominal scales and also has ordered categories
like ordinal scales. But the interval
measurements has no true zero point. Temperature
(80oF and 40oF is 26.7oC and4.4oC) Ratio
Scale In this scale the intervals are consistent
along the entire scale. The ratio measurements
has true zero point. Height of plant, weight
of students, volume, length,
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INTRODUCTION TO STATISTICS

• Questions
• Explain that the given statement follows which
  types of data.
• Sex of insect.
• Weights of plants.
• Major crops of Pakistan.
• Level of satisfaction.
• Teaching standards.
• Temperature measured in Fahrenheit.