Lesson 8

Aim: What is statistics?

Aim: What is statistics?

Problem of the Day:

1. What is a variable?

2. What types of things can be considered variables?

3. How can these variables be measured?

Aim: What is statistics?Statistics is the study of numerical data.

Data: numbers that have meaning.

Aim: What is statistics?Statistics is the study of numerical

data.

Data: numbers that have meaning. 3 Steps in a statistical study:1. The collection of data2. The organization of these data into tables, charts and graphs.3. The drawing of conclusions from an analysis of these data.

Aim: What is statistics?There are two types of variables:

Qualitative:

Quantitative:

Aim: What is statistics?There are two types of

variables:Qualitative: variables that describe qualities of, or categories an individual can be grouped in.

Quantitative:

Aim: What is statistics?There are two types of variables:

Qualitative: variables that describe qualities of, or categories an individual can be grouped in.

i.e. color, gender, race, religion, political party

Quantitative:

Aim: What is statistics?There are two types of variables:

Qualitative: variables that describe qualities of, or categories an individual can be grouped in.

i.e. color, gender, race, religion, political party

Quantitative: variables that can be measured numerically.

Aim: What is statistics?There are two types of variables:

Qualitative: variables that describe qualities of, or categories an individual can be grouped in.

i.e. color, gender, race, religion, political party

Quantitative: variables that can be measured numerically.

i.e. height, weight, temperature, oxygen level, pressure

Aim: What is statistics?A census attempts to count every member of a population.

Why may a census be unreliable?

Aim: What is statistics?Instead of a census, we can take a fair sample of the population.

If the sample techniques favor a certain portion of the population, we say the sample is biased.

Aim: What is statistics?Unbiased samples:

1. Sample sizes should be large

2. Samples should be chosen randomly, so that every member of the population has an equal chance of being selected.

3. Questions should be fair and not favor a particular response.

Aim: What is statistics?Example:

A radio talk show host asks her listeners their opinions of George W. Bush. How could the responses be biased?

Aim: What is statistics?Example:

You want to determine which types of television programs people watch. Where should you conduct your interview?

a) a ball parkb) a supermarketc) a concert hall

Aim: What is statistics?Classwork

Homework

pp. 726–727: ex. 1, 2; Quick check 1, 2p. 727–728: ex. 3–6; Quick Check 3–6

p. 728: ex. 1–4, 7, 9, 10, 13, 14, 15, 17, 20, 22, 25Challenge: p. 731: ex. 28Test Prep: p. 731: ex. 29–31Mixed Review: p. 751: ex. 32, 36 42, 44, 46