1 1 An Overview of Statistics Mrs Leonard

1. 1 An Overview of Statistics Mrs. Leonard Elem Stat

Vocabulary • Data – information coming from observations, counts, measurements, or responses • Statistics – the science of collecting, organizing, analyzing, and interpreting data in order to make decisions

Vocabulary • Population – the collection of ALL outcomes, responses, measurements, or counts of interest Ex. - All the students at CGHS • Sample - subset of a population Ex. - The Senior Class

Population: the responses of all American adults Sample: the responses of the 1708 adults in the survey Data Set: the 939 yes’s and the 769 no’s

Vocabulary • Parameter – numerical description of a Population characteristic • Statistic – numerical description of a Sample characteristic Examples of both are means or standard deviation.

1) Statistic – because we are looking at a sample of MBA’s 2) Parameter – because we are looking at all the graudates from the University of Chicago 3) Statistic – because we are looking at a sample of stores

Vocabulary • Descriptive Statistics – branch of statistics that involves the organization, summarization, and display of data Ex. - 67% of the pets at my house are dogs, while 33% are cats. • Inferential Statistics – branch of statistics that involves using a sample to draw a conclusion about a population Ex. - I have more dogs than cats.

1) Descriptive Statistics – “ 44% “For unmarried men, analysts 70% were 2) of Wall Street in alive at age 65. For married men, 90% were alive year. ” correctly forecasted high-tech earnings in a recent at age 65. ” Inferential Statistics – The Stock Market is difficult to Inferential Statistics – Married men live longer than forecast. unmarried men.

More Practice 1) The US Dept of Energy conducts weekly surveys of 800 gasoline stations to determine the average price per gallon of regular gasoline. On July 10, 1998, the average price was $1. 066 per gallon. a) Identify the population. b) Identify the sample. c) What does the data set consist of?

More Practice 2) In 1997, major league baseball teams spent a total of $1, 119, 537, 215 on players’ salaries. Does this numerical value describe a parameter or a statistic?

More Practice 3) A survey conducted among 1017 men and women by Opinion Research Corporation found that 76% of women and 60% of men had a physical examination within the previous year. a) Identify the descriptive aspect of the survey. b) What inferences could be drawn from this survey?

Answers to More Practice 1) a) All Gas Stations b) The 800 Gas Stations c) Price Per Gallon at each of the 800 Stations 2) Parameter, because we are dealing with a population. 3) a) 76% of women and 60% of men has a physical the previous year b) Women care more about their health

Homework Textbook Pg. 8 -10 (2, 4, 5, 6, 12, 14, 16, 20, 24, 40)