1.1 An Overview of Statistics

Mrs. LeonardElem Stat

Vocabulary

• Data –

• Statistics –

information coming from observations, counts, measurements, or responses

the science of collecting, organizing, analyzing, and interpreting data in order to make decisions

Vocabulary

• Population –

• Sample -

the collection of ALL outcomes, responses, measurements, or counts of interest

subset of a population

Ex. - All the students at CGHS

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 –

• Statistic –

numerical description of a Population characteristic

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’s2) Parameter – because we are looking at all the graudates

from the University of Chicago3) Statistic – because we are looking at a sample of stores

Vocabulary

• Descriptive Statistics –

• Inferential Statistics –

branch of statistics that involves the organization, summarization, and display of data

branch of statistics that involves using a sample to draw a conclusion about a population

Ex. - 67% of the pets at my house are dogs, while 33% are cats.

Ex. - I have more dogs than cats.

1) Descriptive Statistics – “For unmarried men, 70% were alive at age 65. For married men, 90% were alive at age 65.”

Inferential Statistics – Married men live longer than unmarried men.

2) Descriptive Statistics – “44% of Wall Street analysts incorrectly forecasted high-tech earnings in a recent year.”

Inferential Statistics – The Stock Market is difficult to forecast.

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)b)c)

2)

3) a)

b)

All Gas StationsThe 800 Gas StationsPrice Per Gallon at each of the 800 Stations

Parameter, because we are dealing with a population.

76% of women and 60% of men has a physical the previous year

Women care more about their health

Homework

TextbookPg. 8-10

(2, 4, 5, 6, 12, 14, 16, 20, 24, 40)