Statistics with Economics and Business Applications. Chapter 1 What is Statistics? Inference process, population, sample . The Importance of Statistics. Statistics is the science of collecting, organizing, analyzing and interpreting numerical facts which we call data.
Chapter 1 What is Statistics?
Inference process, population, sample
Statistical thinking will one day be as necessary for efficient citizenship as the ability to read and write.
USA Today, 9/4/04
Bush, Kerry differ on strength of economy.
Bush and Kerry both chose Ohio for their stage at the beginning of the Labor Day weekend, traditionally viewed as the kickoff for the fall campaign. "They promised to create 6 million jobs, and guess what? They're about 7 million short," said Kerry.
Bush seized on new employment numbers showing 144,000 new jobs were added to payrolls as evidence of an improving economy. Kerry said it merely confirmed that the president's term would probably end with a net loss of jobs, the first since the Great Depression.
Statistics provides tools that you need in order to react intelligently to information you hear or read.
We are not saying that each one of these claims is true!
Prize Categories and Odds:
Match Odds 1 in
All 5 of 5 And Mega 41,416,353
All 5 of 5 1,592,937
Any 4 of 5 and Mega 197,221
Any 4 of 5 7,585
Any 3 of 5 And Mega 4,810
Any 3 of 5 185
Any 2 of 5 And Mega 361
Any 1 of 5 And Mega 74
None of 5, Only Mega 49
A population is any entire collection of people, animals, plants or things from which we may collect data. It is the entire group we are interested in, which we wish to describe or draw conclusions about.
In order to make any generalizations about a population, a sample, that is meant to be representative of the population, is often studied.
A sample is a subset of measurements selected from the population of interest.
A Time Magazine/CNN pool of 1500 adult American conducted on January 7, 2002 shows that 618 said the "approve", 702 "disapprove" and 180 either declined to answer or has no opinion.
The ratio of the mass of the earth to that of the moon were obtained during several different spacecraft flights: 81.3001, 81.3015, 81.3006, 81.3011, 81.299, 81.3015, 81.3005, 81.3021. These number differ form one another (and presumably form the true ratio) because of measurement error.
x x x
x x x xx
x x xx
xx x x x x x
x x x x x
on Sample units
Environmental Protection Agency (EPA) has accused Shell Oil Company of violation environmental regulations at its refinery located in Huston during the year 2001. The regulations state that the average petroleum leaked into the ground at the refinery must not exceed 100 gallons per day during any calendar year. Fine for violating the regulations is $1,000,000.
EPA regulators visited the refinery on eight days in December, 2001 and measured the petroleum leaked in gallons as 110,96,104,101,87,99,116,108.
The Six Step Inference Process:
I. What’s in this lecture?
1. inference process
2. population and samples
II. What's in next lecture?
Read Chapters 1 and 2.