Definition of Statistics Basic Statistical Concepts

1. Statistics
Chapter 1

2. Statistics
• status, census
• as a science
“ a collection, organization,
presentation, analysis, and
interpretation of data”
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3. Descriptive Statistics
• Includes anything Answers questions such
done to data which is as
designed to Who… Who performed better in the
entrance examination?
summarize or
describes, without What are the highest and
going any further, that What… lowest scores obtained by
students in the test?
is without attempting What is the most populated
to infer anything that school in Metro Manila?
goes beyond the data How many students are
themselves. How…
interested to take Statistics
online?
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4. What are the Roles and Principal
Objectives of Descriptive Statistics
as a Scientific Discipline
• What kind of data to be collected?
• How much data need to be collected?
• How should we organize the data?
• How should we interpret the data?
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5. Most Pinoys Believe in Love at First Sight
(Source: Philippine Daily Inquirer, February 15, 2002)
According to the survey made by the Social Weather Stations
(SWS) in November, MAJORITY of Filipinos believe in love at first sight
and say each person has only one true love. Belief in love at first sight is
higher among middle-aged and older Filipinos compared to younger
ones, and higher among Filipinos with less education. Compared to a
February 2000 Gallup poll in the United States, the SWS survey found
that more Filipinos believe in love at first sight (72% compared to 52%
among Americans), have experienced falling in love at first sight (64%
compared to 40% among Americans), and believe in one true love (84%
compared to 74% among Americans). When asked about their past
relations, SWS found that 70% of Filipino men have experienced falling
in love at first sight, as compared to only 58% of Filipino women. Sixty-
seven percent (67%) of married Filipinos are more likely to say they
have experienced falling in love at first sight, compared to 54% of single
Filipinos.
The SWS said it surveyed 1,200 adults. The results have a 3%
margin of error.
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6. Terms Used in
Statistics Population Parameter
Population
- is the set of measurements
corresponding to the entire collection We may wish to
of units about which the information is
sought.
draw conclusions
- is the group of objects about which about the recovery
conclusions are to be drawn. rate of 4000 college
Parameter
students by studying
- is any numerical value which a sample of 300
describes a population
students from the
Sample population.
- the set of measurement that are
actually collected in the course of the
investigation.
- is the portion of the subset of objects
Sample
drawn from the population.
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7. Population Parameter Sample
A typical television We may wish to
network surveys uses a draw conclusion
sample of 2000 about how Metro
households and the Manilans vote in the
results are used to form coming presidential
conclusions about the
population of all
election by studying
26,000,000 households a sample of 1000
in the country. persons from this
population.
parameter not indicated
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8. Classification of Data
are attributes which cannot be
QUALITATIVE
subjected to meaningful
arithmetic.
1) color of the eye
Qualitative Variables
- measure a quality 3) position in an organization
or characteristics on each 5) Rate of politician (e.g. excellent)
individual or object,
6) state of our forest
distinguished by some
nonnumeric characteristics.
QUANTITATIVE
are numerical in nature and
therefore meaningful 2) number of computers in a room
arithmetic can be done. 4) number of students enrolled in NEU
Quantitative Variables 7) temperature in Baguio City
- measure a numerical
8) amount of time to finish the test
quantity or amount on each
individual or object. 9) scores in exam
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9. QUANTITATIVE
- assume exact - assume the infinitely
values only. It can assume many values corresponding to
only a finite or countable the point on a line interval in
number of values. Decimals such a way that there are no
have no meaning. gaps or interruptions. Decimals
have meaning.
DISCRETE CONTINUOUS
2) number of computers in a room 7) temperature in Baguio City
4) number of students enrolled in
8) amount of time to finish the test
NEU
9) scores in exam
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10. Scales of Measurement
NOMINAL ORDINAL
-categorical INTERVAL RATIO
-names, labels,
or categorized
1) The different only
1) sizes of t-shirts
students’ (e.g. small) do
-numbers 1) honor of
organization not mean students 1) length of movies
2) The survey 2) rating of
anything 2) ranking in a 2) number of votes
politician (e.g.
responses of yes, contest
poor)
no or undecided
-numerical -numerical
-categorical
-numbers are -numbers are
-categorical -numbers are used
used to label used
-names, labels, -differences
and categorize and rank -differences
between data between data
only -differences values are
between data values are
-numbers don’t meaningful meaningful
mean anything values are
meaningless -no zero -have zero
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11. ACTIVITY NO. 2
Prof. Amelia F. Asaytono
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12. Activity No. 1b
A restaurant wants to get feedback from its 1000 customer on the quality of food and
services it offers. Below is a sample of the survey questionnaire that they distribute to
their 100 customers.
Using the sample survey, identify at least five variables that you can classify as
QUANTITATIVE or QUALITATIVE. For QUALITATIVE VARIABLE, determine if it is
NOMINAL or ORDINAL. For QUANTITATIVE VARIABLE, determine if it is RATIO or
INTERVAL and DISCRETE or CONTINUOUS.
Name: Quality of Food
________________________________ _____VS _____S _____US
Age: _____________ Gender: Serving Size
_________________ _____VS _____S _____US
Nutritional Orientation Services
____ Vegetarian ____ Non-vegetarian _____VS _____S _____US
How often do you go to this restaurant?
____ once a week VS - Very Satisfactory
____ twice a week S - Satisfactory
____ more than twice a week US - Unsatisfactory
____ others
What type of orders do you usually Remarks/Comments/Suggestions:
take? __________________________
____ solo meals ____ group meals __________________________
____ combo meals ____ ala carte
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13. References
High School Statistics by Campeña
Basic Statistics with Probability by
Hernandez
Elementary Statistics by Blay
Introduction to Probability and
Statistics by Calingasa
PowerPoint Lay-out
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