1. Statistic Descriptive
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

2. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Lecturer
Ir. Muhril Ardiansyah, M.Sc., Ph.D
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

3. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Text
Lind, Marchal, Wathen Statistical Techniques in Business and Economics with Global Data Sets. Mc Graw Hill International Edition.
Note: Student must bring the
textbook to the class, since we
discuss case and examples from the
textbook.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

4. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Blog
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

5. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Grading
The grading will be used based on the following components:
Participation : 10 %
Homework / Quiz : 20 %
Mid term exam : 30 %
Final exam : 40 %
TOTAL : 100 %
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

6. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Rules In Class
Turn Off HP.
Late more than 15 minutes cannot attend the class.
07:45 am is the latest time to enter the class.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

7. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Materials
Ch 1. What is statistics?
Ch 2. Describing data: frequency tables, frequency distributions, and graphic presentation.
Ch 3. Describing data: numerical measures.
Ch 4. Describing data: displaying and exploring data.
Ch 5. A survey of probability concepts.
Ch 6. Discrete probability distributions.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

8. Materials (continued)
Ch 7. Continuous probability distributions.
Ch 8. Sampling methods and the central limit theorem.
Ch 9. Estimation and confidence intervals.
Ch 10. One sample tests of hypothesis.
Ch 13. Linear regression and correlation.
Ch 16. Time series and forecasting.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

9. Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

10. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Why Study Statistics?
Numerical information is everywhere.
Statistical techniques are used to make decisions that affect our daily lives.
Knowledge of statistical methods will help you understand how decisions are made and give you a better understanding of how they affect you.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

11. What Is Meant By Statistics?
The science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making more effective decisions.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

12. What Is Meant By Statistics?
Chart 1-1 Page 5.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

13. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Frito Lay Volume and Share of Major Snack Chip Categories in US Supermarkets
Potato Chips 64%
Rest
Tortilla Chips 75%
Rest
Pretzels 26%
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

14. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Types Of Statistics
Descriptive statistics.
Inferential statistics.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

15. Types Of Statistics (continued)
Descriptive statistics:
Methods of organizing, summarizing,
and presenting data in an informative
way.
Example:
The population of the United States
was in 1960
in 1970
in 1980
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

16. Types Of Statistics (continued)
Inferential statistics (statistical
inference):
The methods used to estimate a
property of a population on the basis of
a sample.
Population:
The entire set of individuals or objects
of interest or the measurements
obtained from all individuals or objects of interest.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

17. Types Of Statistics (continued)
Sample:
A portion, or part, of the population of
interest.
Reasons for sampling?
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

18. Types Of Statistics (continued)
Population:
all items.
Sample:
items selected from the population.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

19. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Types Of Variables
Quantitative.
Qualitative.
Qualitative variable (attribute):
Characteristic being studied is non
numeric.
Such as: gender,
Religious,
State of birth,
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

20. Types Of Variables (continued)
Quantitative variable:
Characteristic being studied is numeric.
Quantitative variables:
1. Discrete.
2. Continuous.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

21. Types Of Variables (continued)
Discrete variables:
Assume only certain values, and there are
“gaps” between the values.
Example: number of bedrooms in a house.
Continuous variables:
Assume any value within a specific
range.
Example: weight.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

22. Types Of Variables (continued)
Chart 1-2 Page 9
Types Of Variables
Qualitative
Quantitative
Discrete
Continuous
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

23. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Levels Of Measurement
Nominal level data.
Ordinal level data.
Interval level data.
Ratio level data.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

24. Levels Of Measurement (continued)
Nominal level data:
Data categories are represented by labels or names.
Even when the labels are numerically code, the data categories have no logical order.
Table 1-1 Page 10
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

25. Table 1-1 Source Of World Oil Supply For 2004
Millions Of Barrels Per Day
Percent
OPEC
32.91
39.7
OEDC
22.76
27.4
Former USSR
11.33
13.7
China
3.62
4.4
Other
12.35
14.9
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

26. Levels Of Measurement (continued)
Ordinal level data:
Data classifications are represented by sets of labels or names (high, medium, low) that have relative values.
Because of the relative values, the data classified can be ranked or ordered.
Table 1-2 Page 11
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

27. Table 1-2 Rating Of A Finance Professor
Frequency
Superior 6
Good 28
Average 25
Poor 12
Inferior 3
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

28. Levels Of Measurement (continued)
Interval level data:
Ordinal level.
The difference between values is a constant size.
Data classification are ordered.
Equal differences in the characteristics are presented by equal differences in the measurements.
Table Page 12
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

29. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Table Page 12
Size
Bust (In)
Waist (In)
Hips (In) 8 32 24 35 10 34 26 37 12 36 28 39 14 38 30 41 16 40 43
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

30. Levels Of Measurement (continued)
Ratio level data:
Has all the characteristics of the interval level.
The 0 point is meaningful.
The ratio between two numbers is meaningful.
Such as: money,
weight,
Table 1-3 Page 13
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

31. Table 1-3 Father-Son Income Combination
Name
Father
Son
Lahey $
40 000
Nale
90 000
30 000
Rho
60 000
Steele
75 000
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

32. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Ethics And Statistics
Practice statistics with integrity and honesty.
Urges us to do the right thing when collecting, organizing, summarizing, analyzing, and interpreting numerical information.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

33. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Homework
No. 9 Page 16.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.

34. Ir.Muhril Ardiansyah,M.Sc.,Ph.D.
Quiz
For the following questions, would you collect information using
a sample or a population? Why?
1.a. Statistics 201 is a course taught at university. Prof.
Verage has taught nearly 1500 students in the course over
the past 5 years. You would like to know the average
grade for the course.
1.b. As part of a research project, you need to report the
average profitability of the number one corporation in the
Fortune 500 for the past 10 years.
1.c. You are looking forward to graduation and your first job as
a salesperson for one of five large pharmaceutical corporations.
Planning for your interviews, you will need to know about each
company’s mission, profitability, products, and markets.
Chapter 1. What Is Statistics?
Ir.Muhril Ardiansyah,M.Sc.,Ph.D.