STATISTICS - PowerPoint Presentation

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STATISTICSSlide2

Some vocab

Statistics

is

the

art of solving problems and answering questions by collecting and analysing data.Data are the facts or information we collect and analyze. (plural)(note datum is the singular term)Data set- a list of unorganized data. Often called the raw dataSlide3

Raw Data

.....just the numbersSlide4

Statistical Investigation

Step 1: Examining a problem which might be solved using data and asking questions (how many students ride bikes to school)

Step 2: Collecting the data

Step 3: Organising the data.

Step 4: Summarising and displaying the data.Step 5: Analysing the data, and making a conclusionStep 6: Writing a report (presenting your findings)Slide5

Census/Sample

A census is a method which involves collecting data about EVERY individual in a

whole

population.

A sample is a method which involves collecting data about a part of the population.Not as detailed or accurate as census, but easier.Slide6

Problems with a sample

A sample can be biased if the data has been unfairly influedned in the collection

p

rocess. A biased sample won’t represent the whole population

Question

: Are you good at climbing trees?Slide7

Other problems

Question:

Do Americans

like cheese burgers???I am American.I like cheese burgers.There fore ALL Americans like cheeseburgers.Valid argument?!?! Could use Logic!A sample must be sufficiently large to represent the whole populationSlide8

Variables in Statistics

Categorical variable – describes qualities or characteristics. Can be divided into

categories.

The information is called categorical data.Examples. Getting to school: Bus, train, bike, car, walking.Color of eyes: Slide9

Variables in statistics

Quantitative variable- has a numerical value, and is often called a

numerical

variable.

The information collected is called numerical data.Can be discrete or continuous.A quantitative discrete variable

takes exact number values. (

Think

counting)

Examples. Number of people in a house hold

The score out of 30 on a test

The number of sunny days in Stavanger. 1,2,3,4,.....Slide10

Variables in Statistics

A quantitative

continuous variable

takes numerical values within a certian CONTINOUS range. (think measuring)

Examples.The weights of new born babiesThe heights of 9th grade studentsTimeSlide11

What do you think?

Classify the following variables as categorical, quantitative discrete, or quantitative continous.

A. The brand of shoes a person wears

B. The number of cousins a person has

C. The temperature of my coffeeD. The number of cars a household ownsE. The voting intention at the next electionF. Cost of houses on a streetG. Height of 11th gradersH. Favorite type of food

I. Town or city where a person was bornSlide12

Presenting and Interpreting Categorical DataSlide13
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What is the PERCENTAGE of the pie I have eaten (estimate)Slide18
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Presenting and Interpreting Numerical Data

Freqency= number of times the data occursMode= most frequently occuring dataSlide23

Presenting and Interpreting DataSlide24

Presenting and Interpreting DataSlide25

Presenting and Interpreting DataSlide26

The Distribution of Data

(going to lunch)Slide27
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OutliersSlide30
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Interesting Statistics

http://www.worldometers.info/

http://www.informationisbeautiful.net/visualizations

/

http://www.babynamewizard.com/voyager#ms=false&exact=falsehttp://news.bbc.co.uk/2/hi/science/nature/7137462.stm