29-Aug-15Created by Mr. S. Gier1 Statistics STATISTICS DEFINED COLLECTING DATA SAMPLING POPULATION & SAMPLE SAMPLING TECHNIQUES

- is the branch of mathematics concerned with the techniques by which information is collected, organized, analyzed and interpreted.

1. It refers to actual numbers derived from data. For example, - the number of medals won in the Asian games. - the number of malnourished children in a barangay. - the attendance figures for a concert.

2. It formally refers to the simple collection, tabulation, and data summation forming meaningful inferences and conclusions.

- Utilizes numerical and graphical methods to look for the patterns in the data set. - Draws conclusions like decisions, predictions or generalizations about the data set.

1. The increasingly quantitative approach employed in all the sciences, in business and in many activities that directly affect the lives of people requires study. For example, - evaluation of antipollution control. - evaluation of traffic in the city. - study of diet and longevity. - study of communicable disease - evaluation of teaching techniques and curriculum

2. The amount of statistical information that is collected, processed and disseminated to the public has increased tremendously such that more persons with knowledge of statistics are needed to collect the right data, analyze the data wisely, and take part in all the planning. Back to page 1

 A statistician is someone who is particularly versed in the ways of thinking necessary for the successful application of statistical analysis. Often such people have gained this experience after starting work in any of a number of fields.statisticiannumber of fields

 There is also a discipline called mathematical statistics, which is concerned with the theoretical basis of the subject.

 The word statistics can either be singular or plural. When it refers to the discipline, "statistics" is singular, as in "Statistics is an art."

 When it refers to quantities (such as mean and median) calculated from a set of data, statistics is plural, as in "These statistics are misleading."

Some scholars pinpoint the origin of statistics to 1663, with the publication of Natural and Political Observations upon the Bills of Mortality by John Graunt. Early applications of statistical thinking revolved around the needs of states to base policy on demographic and economic data, hence its stat- etymology.John Grauntstat- etymology

Its mathematical foundations were laid in the 17th century with the development of probability theory by Blaise Pascal and Pierre de Fermat. Probability theory arose from the study of games of chance. The method of least squares was first described by Carl Friedrich Gauss around 1794.probability theory Blaise PascalPierre de Fermatmethod of least squares Carl Friedrich Gauss The use of modern computers has expedited large-scale statistical computation, and has also made possible new methods that are impractical to perform manually.computers

The scope of the discipline of statistics broadened in the early 19th century to include the collection and analysis of data in general.

 Statistics is also important in many aspects of society such as business, industry and government. Because of the increasing use of statistics in so many areas of our lives, it has become very desirable to understand and practice statistical thinking.  This is important even if you do not use statistical methods directly.

 Today, statistics has become an important tool in the work of many academic disciplines such as medicine, psychology, education, sociology, engineering and physics, just to name a few.

EXTRA CHALLENGE!!!

DIFFERENCE BETWEEN POPULATION & SAMPLE

DIFFERENCE BETWEEN POPULATION & SAMPLE

DIFFERENCE BETWEEN POPULATION & SAMPLE

Try this out…. Study the following situations. Identify the phrase which represents the sample and which phrase shows the population. 1. Mrs. Jara wants to know the nutritional status of the first year students in her school so she got 150 first year students to represent the year level. SAMPLE 150 first year students POPULATION First year students

Try this out…. Study the following situations. Identify the phrase which represents the sample and which phrase shows the population. 2. When Sandra bought a sack of rice, she examined a handful from the sack to check if it is the variety she wants. SAMPLE handful of rice POPULATION a sack of rice or one sack of rice

Try this out…. Study the following situations. Identify the phrase which represents the sample and which phrase shows the population. 3. A doctor wants to know what causes the infection in a patient so he requested for the patient’s blood examination. The medical technologist extracted only 10 cubic centimeters of blood from the patient for examination. SAMPLE 10 cubic centimeters of blood POPULATION Blood

Try this out…. Study the following situations. Identify the phrase which represents the sample and which phrase shows the population. 4. The chef wants to check if the food being cooked tastes as he wants it to be so he tasted a spoonful of it. SAMPLE Spoonful of it POPULATION Food cooked

Try this out…. Study the following situations. Identify the phrase which represents the sample and which phrase shows the population. 5. The school guidance counselor would like to know the course preference of the graduating students in their school so she interviewed 100 of the fourth year students. SAMPLE 100 fourth year students POPULATION Graduating students

What is Statistics?

What is the difference between POPULATION and SAMPLE?

QUIZ….

QUIZ Assume that the following are questions to which you want to find the answer. (i)Ms. Sanchez wants to know the most-liked subject in a school. 1. What must be the population of the study? 2. How will you describe the population? 3. What would be the appropriate sample of the study?

HOMEWORK Give at least two instances which show that Statistics is important in our daily life. Statistics can be very well- used or misused. When is Statistics misused and by whom? Describe how. Write your answers in a paper (one-half crosswise)