For those days when you have absolutely nothing else to do.

Like, you've tidied your room you're that bored

Or for when you have an exam...

By Amy G. (she is a legend)

Presentation of data

Probability Averages

Questionnaires and sampling

( 1 click a box to advance the show...)

Percentages +Savings accounts

( 2 it's totally worth it)

( 3 Otherwise you'll just sit here staring at the contents page...)

( 4 we wouldn't want that now, would we?)

( 5 unless you like that sort of thing...)

( 6 I don't...)

( 7 seriously, click one now...)

THE END IS IN SIGHT(click this if you're done)

Data in a frequency table

Add an extra column to the table so you have 3

Mode = most frequent

Show the full calculator display

The data column is the one that is ordered

You never do averages of averages

Always work back to totals

Number of cars (X)

Frequency F times X

0 5 0

1 18 18

2 23 46

3 14 42

total 50

I want to go back to the awesome contents

(or choose a new topic)

This is so boring, maybe the Next page

Will be more interesting

Grouped frequency tables

This type of frequency table has class intervals

Questions ask for an estimate of the mean- don't just guess!

The mode and the median are both class intervals

Draw a table with 4 columns – data, frequency, midpoint, midpoint x frequency

Moving averages

For a 4 point moving average, take the first 4 values, for a 3 point moving average take the first 3 etc. find the mean of them

Then take the next 4 values starting with the 2nd value and find the mean of them.

(depending on what type of moving average it is, you could have a different number of values.)

Carry on until you get to the end of the values

Plot the moving average in the middle of the data it represents e.g. if it is a 3 point moving average, plot it at the 2nd value

I cant tek any more Averages!!! >.<

(contents)

Rush on to the next page, Folks(But not before you read the

facts!)

Primary data- Data you collect yourself (from surveys and questionnaires- face to face, by phone, by post, or via the Internet)

Secondary data-Data that is collected by someone else (from the Internet, newspapers etc)

Primary Data is more reliable because you can be sure of the source, but it can take a long time to collect and costs lots of money. Secondary Data is usually cheaper and easier to get, but it may not be as reliable.

Ooh, this looks a bit hard....

(back to contents)

On the Next page, Enlightenment awaits

This method of sampling is less biased and very useful =)

You split the population into groups called strata and each group is sampled according to it's size.

FORMULA!!!!

( remember this formula- it comes in handy=))

Meh... I knew this...(contents)

Just kidding bout enlightenment, go

to Next page anyways

How likely an event is to happen

Impossible = 0

Certain = 1

Probability can be a fraction, a decimal or a percentage but NEVER a ratio.

P'(event) = Probability of the event not happening

To compare probabilities, change them both to decimals

Events are chosen at random- every event has an equal chance of being chosen

Relative Frequency If you don't have the probability of

something, and you can't calculate it, you can do an experiment to calculate the probability

More trials =Better estimate of the probability =) (its goooood)

Noooo not probability...

(back to contents)

The Next page has a picture

of a fish on it...

Mutually exclusive events can't both happen at the same time- P(A or B)= P(A) + P(B)

Independent events have no effect on each other- P(A and B) = P(A) x P(B)

Combined events

If 2 or more events happen at the same time you need to do a diagram to find out all possible outcomes-

A systematic list

A sample space diagram

A probability tree

Probability trees

These are the most efficient way to show combined probabilities

Write the events across the top

Draw branches for each possible event

Write the probabilities on the branches

Total probability for each set always equals 1

Conditional probability is when the probability is affected by another.Argh still

probability...(contents)

What did I tell you? (he's called Nemo) Next page

Pie charts

Do a table to find the angle for each sector

Pie charts don't give frequencies so be careful when you compare frequencies

Check proportion

Scatter Diagrams

Plot a series of data to see if there is a relationship – correlation

Just because there is correlation doesn't mean that there is a relationship

The Independent variable goes on the X axis

The dependent variable goes on the Y axis

Maybe later ehehehe...

(back to contents)

Use the force (of this button)To go to the next page

Scatter Diagrams

Positive Correlation- as 1 variable increases, so does the other

Negative Correlation- as one variable decreases, the other increases

Line Of Best fit

These should follow the trend of the data

It must go through the mean plot

You can use the line of best fit to extrapolate values, but you need to be careful, as sometimes they aren't relevant

You may need to work out the equation of the line using the equation Y=MX+C

zzzzzzzzzzzz...(back to contents)

Hurry on to the Next page, Peeps XD

Frequency Polygons

These are used to compare sets of data

Plot the frequency against the midpoint of the class interval

Histograms

A bar chart is actually a type of Histogram with equal class intervals

The bars always touch in a histogram

The area of the bars represent the frequency

Label the vertical axis frequency density

Work out the vertical scale to complete the histogram

Must...play...ps3!(back to

contents)

Something interesting

might happen on the next page

Histograms continued

Method

Work out the vertical scale and complete the histogram

To work out the vertical scale, find a value that is in both the table and the histogram

Cumulative Frequency Graphs:

Add a 'Cumulative Frequency' column to the table

Plot the end point of the class interval against cumulative frequency (Cumulative frequency is on the Y axis)

For a 'Cumulative frequency polygon' draw straight lines

For values over 50, we use

Because we all need to

know how to do this....(back to contents)

Boo! Eheheh.. maybe

on the Next page?

Box plots

It is easy to compare data in a box plot

You must use the same scale on the axes

Outliers

Outliers are extreme values

1.5 times the IQR above the UQ or below the LQ

Mark with a cross

Kyaaa! I need escape!!(back to contents)

Orange is Interesting=] The Next page

will be normal again

To compare fractions, decimals and percentages, write them as the same form e.g. all decimals

Multiplying factors (they are very important later...)

To increase something by 17%, times it by 1.17

To decrease something by 17% times it by 0.83

To find a number as a % of another

To find an amount before % change

% profit / loss / increase / decrease

Percentage of this I remember = 0

(back to contents)

You're worth it on The Next page

Simple interest

This is the formula for a simple interest account. It gives you the amount of interest you get.

P= principal sum

R= rate of interest

T= time in years

Compound Interest

In a compound interest bank account, the amount of interest is paid into the bank account at the end of the year. The next years interest is calculated on the new amount.

I need to save myself from this!!!

(back to contents)

What did I tell you eheheh...

The E.N.D. is in sight!

(Go to Last page)

Thanks for watching=]

Hope you have learnt something=]Watch it again (it'll only get worse...)

By the way, that album cover is the E.N.D.... get it? The E.N.D. Is in sight?

(oh, I make myself laugh)Never mind then... Bye =]