Interval Estimates for proportion NEW.pptx

mathematics senior high

1. Statistics and Probability

2. HOUSE RULES Always wear your face mask. Observe physical distancing. Follow directions. Raise your hand to speak.

3. Estimation

4. 95% is an example of a confidence interval.

5. B L U F F

6. 99% is an example of a confidence level.

7. F A C T

8. An interval estimate is a range of values.

9. F A C T

10. Sample proportion is an unbiased estimate of population proportion.

11. F A C T

12. If 95% confidence is selected, then α =.10.

13. B L U F F

14. The expression 95% is the same as .  

15. B L U F F

16. If α = 0.01, the confidence coefficient is 2.58.

17. F A C T

18. If α = 0.10, the confidence coefficient is 1.645.

19. F A C T

20. Because of Covid – 19 Pandemic, the company where Liza’s father worked in has closed. Wanting to earn money for their family to survive, he has thought of putting up and running a business, particularly food business, but he does not know what food business is feasible in their community. What strategy or way can be best done by Liza’s father in starting such business?

21. What product will be offered? Who will buy the product? Why will they buy the product?

22. How will the product be promoted, offered, and sold? Who are my competitors? How is it different or better than other products?

23. Interval Estimates of Population Proportion

24. Today’s Target: compute for the confidence interval estimate of the population proportion. solve problems involving confidence interval estimation of the population proportion. draw conclusion about the population proportion based on its confidence interval estimate

25. Proportion – is a fraction expression where the favourable response is in the numerator and the total number of respondents is in the denominator.

26. Example 1: What PRODUCT should I offer? The pie chart presented shows the survey conducted by Liza to help his father determine what food combo is preferred by people in their community. They interviewed 200 people to determine their preferences. With 95% confidence, what interpretation can we make as regards the probability that all people prefer milk tea and burger combo?

27. With 95% confidence, we can assert that the interval from 25% to 37% contains the true proportion of people who prefer burger and milk tea.

28. EXAMPLE 2: Who will buy my Product? AGE f 10 years old and below 25 11 - 15 45 16 - 20 70 21 – 25 32 26 - 30 15 30 years old and above 13 TOTAL 200

29. The table shows the number of people of a specified age bracket who prefer milk tea and burger. Use a 90% confidence to estimate the true proportion of population with ages 16 – 20 years old who prefer milk tea and burger.

30. We are 90% confident that the interval from 29% to 41% contains the true proportion of people with ages 16 – 20 who prefers milk tea and burger.

31. EXAMPLE 3: Why will they buy the Product?

32. The bar graph shows what customers consider in buying a product. Estimate the true proportion of customers who consider the price in selecting a product. Use 99% confidence level.

33. We can say with 99% confidence that the interval between 22% and 38% contains the true population proportion of customers who consider the price in buying a product.

34. ACTIVITY

35. In a survey, 500 customers were asked what type of promotional ads attract them in buying food products. 205 of them bought products showcased on social media. Use a 95% confidence to estimate the proportion of all customers who bought products showcased on social media.

36. In a job satisfaction survey among faculty members in a university, 400 employees were asked if they were satisfied with their jobs. There were 205 who responded YES. Use a 95% confidence to estimate the proportion of all faculty members who are satisfied with their jobs.

37. Rizza conducted a poll survey in which 520 of 1200 randomly selected voters indicated their preference for Candidate A. Using 90% confidence level, what is the true population proportion of voters who prefer Candidate A?

38. The registrar of a university has conducted a pre-survey of selected courses in the university. Of 850 randomly selected students, 450 have said they like Science course. With 95% confidence, what interpretation can we make regarding the probability that all students in the university want to major in Science?

39. A Physical Education major sought to determine whether all Filipinos are familiar with the game “ sipa ”. Among 1500 respondents, 358 knew the game. Use a 99% confidence to estimate the population proportion. Interpret the data.

40. In your group chat, answer the poll survey: What set-up is convenient for you? Face – to – face classes Printed modular distance learning Digital modular distance leaning Using the result of the poll survey, what is the true population proportion of students who prefer (a) face to face classes, (b) printed modular distance learning, and (c) digital modular distance learning. Use 95% level of confidence.