Chapter 1
Basic Statistical Concepts
Dr. Ruben A. Sanchez
Associate Professor 2
What is the role of
STATISTICS in research?
Why do you need STATISTICS ?
DATA
Adage of Research: G I G O
Data may range from single
frequency tables to a very complex
multivariate analysis such as
forecasting for time series data or
structural equation modeling
Why do you need STATISTICS ?
➢ All real-world processes exhibit
variability which is the result of changes
in the underlying conditions
➢ In most application, it is not possible to
study the whole population – there is
always an element of uncertainty
➢ It provides evidence to support an
opinion or judgement
Some Applications of
Statistical Analysis
◦ Visualization of company’s performance over
time and in real-time
◦ Comparing the effects of five kinds of fertilizers
on the yield of a particular variety of corn
◦ Determining if there exists an association
between income and educational attainment
◦ Comparing the effectiveness of two diet
programs
◦ Assessment of job satisfaction scores
◦ Evaluation of student performance
Aim of Statistical Analysis
It aims to uncover structure in data, to explain trends, variation…
DATA INFORMATION KNOWLEDGE INSIGHTS
◦Weights of people in your class are not the same.
◦Banks’ reserves vary from bank to bank.
◦Peso dollar exchange rate varies from day to day.
◦Economic growth rates of countries vary.
Descriptive Statistics and Inferential Statistics
Two Classification of Statistics
1. Descriptive Statistics
2. Inferential Statistics
• With descriptive statistical
analysis, one is simply describing
what is or what the data show.
• It uses graphical numerical
descriptions to give a picture of a data
set.
Generalization via Sample
Descriptive Statistics
Inferential Statistics
Example. Determine whether the following
statements use the area of descriptive analysis
or inferential analysis.
1. A teacher wishes to determine the
percentage of students who passed the
examination. Answer:DS
2. A basketball player wants to estimate his
chance of winning the most valuable player
(MVP) award based on his current season
averages and the average of his opponents.
Answer: IS
3. A student wishes to determine the average
monthly expenditures on school supplies for
the past five months. Answer: DS
1. Nominal
o Numbers or symbols used to classify
o Categories are distinct, mutually exclusive, and mutually
exhaustive
o Categories are of equal importance Example: Sex (1-
Male, 0-Female)
2. Ordinal
o Accounts for order; no indication of distance between
positions. Example: Size of Shirt (Small, Medium, Large)
3. Interval
o Equal intervals; may be added or subtracted;
no absolute zero
o Examples: Temperature, IQ
4. Ratio
o Has absolute zero
o Examples: Income, production
Sample Exercise
Determine if the data is Quantitative or qualitative. If
quantitative, specify if discrete or continuous. Further,
determine the level of measurement.
1. Amount of travel expense of employees (actual amount in pesos)
Answer: Quantitative, continuous, interval
2. Zip code
Answer: Qualitative, Nominal
3. Membership in an organization (member or non-member)
Answer: Qualitative, nominal
4. Length of service (in actual number of years)
Answer: Quantitative, discrete, ratio
5. Satisfaction with the training program (Very satisfied, satisfied, dissatisfied, very
dissatisfied)
Answer: Qualitative, ordinal
6. Reproductive Health Bill (oppose, in favor)
Answer: Qualitative, nominal
7. Number of employees given bonuses
Answer: Quantitative, discrete, ratio
What to comply?
1. Formative Assessment 1
2. Workshop 1
3. Workshop 2
4. Deadline: September 7, 2024
11:59PM
Asynchronous on August 31
You will work with the three
requirements
