The document introduces statistics as the science of collecting, organizing, presenting, analyzing, and interpreting numerical data to assist in decision making. It explains that statistics are used broadly across many fields including marketing, accounting, quality control, consumers, sports, hospitals, education, politics, and medicine. The document also defines key statistical terms like population, sample, descriptive statistics, inductive statistics, and the different levels of measurement for data.
2. What is Meant by
Statistics?
Statistics is the science
of collecting, organizing,
presenting, analyzing,
and interpreting
numerical data to assist
in making more
effective decisions.
3. Who Uses Statistics?
Statistical techniques are
used broadly by
marketing, accounting,
quality control,
consumers, professional
sports people, hospital
administrators,
educators, politicians,
physicians, and many
others.
4. Two important terms used
in the study of Statistics
A Population
is collection of all
possible
individuals,
objects, or
measurements of
interest.
A Sample is a
portion, or part,
of the population
of interest
5. Types of Statistics
EXAMPLE : According to the
data of General Electric, it
reported that the production of
washing machine from 2003 to
2007 were 1,000 , 1,200 , 1,300 ,
1400 and 1,500.
Descriptive Statistics: Methods of organizing,
summarizing, and presenting data in an informative way.
Inductive Statistics: A decision, estimate,
prediction, or generalization about a population, based on
a sample.
9. Levels of
Measurement
During a taste test
of 4 soft drinks,
Coca Cola was
ranked number 1,
Dr. Pepper number
2, Pepsi number 3,
and Root Beer
number 4.
Ordinal level: involves data arranged in some
order and usually inequality signs can be used
10. Levels of
Measurement
Temperature on the
Fahrenheit scale.
Interval level
Similar to the ordinal level, with the additional
property that meaningful amounts of differences
between data values can be determined. There is no
natural zero point.
11. Levels of
Measurement
Ratio level: the highest level of data.
Meaningful ratio between value. In addition, it
resulted in a pure or distance number and it is not
expressed in units
12. Practice
■ Suppose that we are given complete
information about the number of patients
admitted and the length of their stays at a
certain hospital during a certain year. Give
one example each of problems in which
we would consider this set of data to be
a. population
b. sample
13. Practice
■ In the years 2004, 2005, 2006 and 2007, Medan had 1.4 , 1.6, 1.8,
2.0 millions population. During the same year, Binjai (in million) 0.6,
0.7, 0.9, and 1.0 population. Which of the following conclusions can
be obtained from these figures by purely descriptive methods and
which require generalizations (inductive statistics)?
a. Medan’s populations grew to 2 (millions) from
the year 2004 to 2007.
b. Binjai’s populations increased from the year 2004 to
2007.
c. Medan’s populations will exceed 3.0 millions within the next 5
years.
d. From these two cities, populations in Binjai are lesser than the
populations in Medan.
e. Population rates in Medan must have been about 20% less in the
year of 1998 than it was in 2004.
14. Practice
■ The “Brastagi” fruit store has asked you for
information about apples that you bought. For
each question, identify each types of data
requested as either categorical data or numerical
data. When numeric data, identify the variable as
discrete or continuous.
1. What is the weight of the apples?
2. In what country this apples are imported?
3. What’s the color of your apples?
4. How many apples that you bought?
15. Practice
■ What is the level of measurements for each of the
following variables?
1. Subjects that being taught in IT&B
campus, like Accounting, Marketing,
Statistics and Organizational Behavior.
2. Students IQ ratings.
3. Number of hours employees work per week.
4. Three largest corporations ranked by
sales (Toyota, Honda, and Suzuki).
5. Male employees pants size
16. Assignments
■ Which of the each following variables can
be classify to quantitative or qualitative.
a. Age
b. Gender
c. Class rank
d. Martial Status
17. Assignments
■ What is the level of measurement for each
of the following variables?
a. The number of papers sold each
Sunday during 2004
b. The departments, such as editorial,
advertising, sports, etc
c. Student’s money for a week
d. Barcelona’s Temperature
18. Assignments
■ Developer of Cemara Asri invited a sample of
258 people to look at the newly build types of
villa. Of the 258 sample, 180 said that they
would purchase the villa if it is marketed
a. What could Developer of Cemara Asri report
regarding acceptance of the villa?
b. Is this an example of descriptive statistics or
inferential statistics? Explain.
