So, I have a few questions to ask about our prime suspect.
Oh, 7.
(CHUCKLES) Yeah, he's a bit of an odd fella, isn't it?
Numbers can be pretty useful tools,
giving us vital bits of information.
I was sitting in maths class...
And they can help us piece together a story.
..when I looked over and saw it.
7 'ate' 9.
It's why if you watch or read the news,
you often see stuff like this.
Cases started falling across the country.
All of these graphs and percentages and numbers
are examples of statistics.
That's a branch of maths that involves collecting, analysing
and making sense of data.
You can think of it as facts supported by numbers,
and we use it all the time.
A lot of the statistics we see use smaller groups of people,
numbers or data to make a prediction about bigger groups.
So, say you wanted to know what Australia's favourite sport was,
you could ask 1,000 random Aussies and, with the power of statistics,
get a pretty good idea what the rest of us think.
The larger the sample that you have,
the more confidence you have in the conclusion that you reach.
Stop roamin', numeral, and sit down!
But you have to be careful about believing everything the numbers say.
Now I've been going over the maths and something doesn't add up.
Imagine instead of asking 1,000 people
about their favourite sport,
I only asked 10,
that's not going to give me a very good idea
about what the whole population thinks.
Now imagine if those 10 were my basketball team.
Chances are I would get a result that looks a bit like this.
This is called sampling bias
and it's something you may have come across in the news.
If you see, you know, survey results and statistics in the media it's -
how is that number being calculated?
If it's a survey, who has been asked their opinion?
If you're wanting to know how people are voting,
but only young people are being asked their opinion,
well, you're not getting a representative sample.
Casey is a data analyst at the ABC so he deals with a lot of statistics
and he says it's important to look closely
at where data is coming from,
whether it's reliable,
and whether we're getting the full story.
What are you looking at?
Take a squiz at this graph of global temperatures.
If you look between 2015 and 2018,
you might think things are getting colder.
But zoom out a little and add a few more years
and the picture starts to become a lot clearer.
It's also important to look at the numbers on the sides of graphs,
or the axes,
to see what they're actually telling us.
Say it's a graph comparing the heights of me and Matt.
Gee, I look pretty tall.
But have a gander at the numbers on the side
and you'll see we're only looking at a few centimetres.
Stretch all of these numbers out to zero
and we're really not that different.
Casey says understanding how statistics work
has been particularly important in 2020.
We have the biggest global pandemic in 100 years,
the only way to understand the way that this virus is spreading
is through numbers and the numbers are really complicated.
Complications aside,
you could say statistics are more important than ever,
so long as we know how to understand them
and when we can trust the numbers.
Right, we've done some digging,
checked your axis and your sample size,
and you seem like a rational number.
Great. So, uh, can I go?
You're free to go. Yeah, yeah. OK.
Just let me jot down your number, in case we need you again.
Yeah, sure, um, one.