1. Chapter 7: Data Collection and Presentation Mathematics Department Corpus Christi School

2. When you want to buy a phone, which brand will you buy? Apple or Samsung?

3. Statistics  A branch of Applied Mathematics  Involves in collection, organization, presentation, and interpretation of data.

4. Statistics Statistics involves:  Data Collection;  Data Presentation; and  Describing the data collected

5. What are Data? Data is collected from two main sources: 1.Population 2.Sample

6. Example 1 A pharmaceutical company wishes to monitor their products. A. The population for this study is the totality of all medicinal drugs produced by the company. B. The sample would be all the drugs examined for quality control on a particular day.

7. Example 2 A polling firm wishes to determine the voting preferences of Filipino voters for the next election A. The population for this study is the totality of all Filipinos of voting age. B. The sample would consists of all voters surveyed by the firm.

8. Example 3 A survey is being conducted to determine the TV viewing preferences of Filipino HS students. A. The population consists of all Filipino HS students. B. The sample consists of HS students included in the survey.

9. Therefore: A. Population – totality of all individuals or objects from which the required information is to be obtained. B. Sample – a subset or part of the population.

10. Variable - Is the particular information of interest to be obtained from either the population or sample.

11. Example 1 A pharmaceutical company wishes to monitor their products. The variable is the number of percentage of products passing the quality control test

12. Example 2 A polling firm wishes to determine the voting preferences of Filipino voters for the next election The variable is the voting preference of the Filipino voters

13. Example 3 A survey is being conducted to determine the TV viewing preferences of Filipino HS students. Some of the variables that may be studied include favourite television shows, preferred genre, and number of hours.

14. Review: Population Sample Variable Data

15. Observation/Scores -The values of the variable

16. Example 4 If the variable of interest is favourite sports. Some of the values are basketball, swimming, tennis, taekwondo, badminton and archery

17. Example 5 If the variable of interest is number of hours of sleep. Some of the values are 6, 7, and 8.

18. Example 6 If the variable of interest is number of siblings. Some of the values are 0, 1, 2, and 3.

19. Types of Variables 1. Qualitative – variables that measure quality or characteristic. Ex. Hair Color, Gender, Religion 2. Quantitative – variables that measure a number or an amount. a. Discrete – obtained by counting b. Continuous – obtained by measuring

20. Classify the ff: Nationality Weight Credit Limit Voting Preference Hair Color Temperature Shirt size

21. Identify a possible sample: 1. Students enrolled in schools in Cagayan de Oro 2. Electric consumption in Cagayan de Oro 3. Philippine Dialects 4. Religions of the World 5. Average salaries of employees in the Philippines

22. Identify the Variable of interest 1. Survey to determine the choice of president for first time Filipino Voters 2. Study to determine the career- preferences of graduating Filipino High School Students

23. 3. Study to determine the leading causes of death among Filipino Males 4. Survey to determine the most preferred movie genre of Filipinos Identify the Variable of interest

24. Descriptive – concerned with describing the characteristics and properties of a group of person, places or things. Division in Statistics

25. Inferential – is used to draw inferences, prediction, conclusion and information about the properties or characteristics of a large group from the information from the small group. Division in Statistics

26. Identify the division of Statistics: 1. A teacher computes the average grade of her students and then determines the top ten. 2. A manager of business firm predicts future sales of the company based on the present sales.

27. Identify the division of Statistics: 3. A psychologist investigates if there is a significant relationship between mental age and chronological age. 4. A researcher studies the effectiveness of a new fertilizer to increasing food production.

28. Identify the division of Statistics: 5. A school administrator forecasts future expansion of a school.

29. Is any numerical or nominal characteristic of a population. It is a value or measurement obtained from the population. Parameter

30. Is an estimate of a parameter. It is a value or measurement obtained from a sample. Statistic

31. 1. Discrete Variable 2. Continuous Variable 3. Dependent Variable 4. Independent Variable Classifications of Variable

32. Obtained from counting Ex. Number of students in 1I is 30. Discrete Variable

33. Obtained through measuring Ex. Height of a Building Continuous Variable

34. A variable which affects or influences the dependent variable. Independent Variable

35. The variable which is affected or influenced by another variable Dependent Variable

36. A study to determine the favorite brand of shoes of Corpus Christians IV – Quality of shoes, price of shoes, design, size, color DV - Brand

37. 1. Nominal Scale 2. Ordinal Scale 3. Interval Scale 4. Ratio Scale Scales of Measurement

38. The assignment of symbols or numerals to objects or events. Measurement

39. It is used when we want to distinguish one object from another for identification purposes. Ex. Gender, Religion Nominal Scale

40. Data or measure arranged in some specified rank. Ex. Beauty Contest, Runners Ordinal Scale

41. Used when we can say that the object is greater or lesser but we can also specify the amount of difference. Ex. Scores in a Test, Grade Interval Scale

42. It is like the interval unit. This is only used when one object is so many times as large or small as the other. Ex. The weight of the mother is twice as her daughter. Ratio Scale

43. Identify the scale of measurement: 1.Religion 2.IQ Scores 3.Speed of a Car 4.Civil Status 5.Address 6.Size of T-shirt 7.Salary of workers