Instructor: Hello, students.
We are now going to start chapter five
and we are gonna start with problem two.
So first, again, I'm going to read the problem.
Problem two states, hyperlipidemia in children
has been hypothesized to be related
to high cholesterol in their parents.
The following data were collected on parents and children.
So here, we have basically the information
about both the parents or one parent in the columns
and the children information as the rows.
So whenever I see a table like this,
the first thing I do is add the rows and the columns,
and that really, really is very helpful,
and that's what I have basically done here.
So what is the first problem asking us, which is A?
It is asking us what is the probability
that one or both parents are hyperlipidemic?
So...
We have to look at here the numerator.
So the numerator here is asking us
about one or both of the parents' hyperlipidemia status,
so we are going to add them, so both or one parent,
and we are adding their hyperlipidemia status.
And that will be equal to
58 plus 76.
Which is 134.
So again, where did I get those two numbers from,
I want to use another color so you can see it nicely.
So this is where I'm getting the 58 and 76,
because we are talking about both parents
being hyperlipidemic or one parent being hyperlipidemic.
Now, for the denominator, there are no conditions
or stipulations attached.
So that will be our entire cohort, our entire population.
And what is that? That is 223.
So our entire cohort, and again,
I'm going to use a different color this time again.
And that is this, 223.
That is going to be our denominator.
So now to do the calculation, what we have to do, again,
I'm gonna go back to black, the color I was using.
For the calculation, what we have to do is take 134
and divide that by 223.
And what do we get as a result?
We are going to get 0.60 or 60%, so what does this mean?
This means that the probability of one
or both parents being hyperlipidemic is 60%
if the child or the children is hyperlipidemic, okay.
So 60% is the probability, so the probability,
and I'll write it here.
So the probability
of one
or both
parent being hyperlipidemic
60% if the child is hyperlipidemic
based on the values provided on this table.