High in this session, we will wrap up with inferential statistics, so let us discuss about coordination,
cooperation, which is the last topic which we have in invention diagnostics now.
We have already discussed mode for deletion, so we already know what correlation is, right?
Correlation is something which provides us the detection of the relationship between two evils, and
it also provides us the strength of the relationship between the variables.
Right.
So correlation is what it provides.
Now, what is the index?
What is the barometer which actually provides this relationship the strength of the relationship between
the variables that is called correlation coefficient.
So the value of correlation coefficient will range from minus one to one, and it is calculated.
Now, if the value is calculated, which is greater than one or less than one, that means that we have
made some mistake in calculating the correlation for fishing.
And the correlation of minus one shows that there is a negative correlation, while a correlation coefficient
of one which shows that it is a perfect positive correlation.
And a correlation of zero point zero shows that there is no relationship between the movement of political.
Here you can see.
That made us say we have to wait with one variable being income and another variable being the age of
the person, but experience of the person.
So as the experience of the person increases, the income of the person is also increasing.
And there is a very strong relationship between these.
Now, here we have a relationship when let's say we have the age of the person, I'm the exercise of
the person.
So let's say we have the exercise of the person and the health issues.
So as the person may increase the exercise, which he is doing, then the number of health issues will
reduce.
So here we have a strong negative correlation.
That is, it is a zero point nine nine that it is a very strong negative relationship.
Now, in case we have a straight line or line, which is more on line, actually, but these are called
nonlinear relationships and then we have not a straight line, nor does or not convict data points.
Then it is called medium or weak correlation.
So here we have a weak to medium good relationship and weak to medium negative relationship.
So this means that it is not a sure thing that if we increase the salary, let's say we increase the
salary of the person so it increases the number of expenses.
So that is not a sure thing.
So these are different kind of relationships, which we can build from correlation coefficient.
Next, what we have is the dog, which you can maybe take a screenshot of and keep as a standard go
to point where you can decide which particular test you want to conduct.
So if you want to conduct a test and you have categorical variables.
Then you will follow this particular line, and in this you have continuous variables, then you can
follow this particular.
So what is it in case you have categorical variables, then you can have this, you can have two samples
at best, or you can have squared this now in case you have continuous values then and if you have a
specific number of samples.
So based on the number of samples, you can decide if let us say we have one.
Sample, if we have two samples and if we have more than two samples, then we then begin to say.
Here you can see if you have more than two samples, then you can apply the unadvertised.
They if you have one sample and you have a standard for population standard deviation, then you can
apply when somebody is if you know the population standard deviation and the sample size is less than
30, you will apply once I repeat this, if the sample size is greater than equal, that you will apply
one sample so you can follow this particular dog to find out which particular test you want to conduct
now.
Next, we will have a look at how you will perform these tests by using a machine instead of doing it
by hand.
So let me show you that so this is one website which we have.
This website is foie gras, five dot com, so you can go to golf bag dot com and you can go to the quick
calculator's.