apparently, according to a paper mark scheme
Anyway im interested in
is a valid probability density function
But if you put the upper limit 2 in you get 2 out, when probability ranges between 0 and 1.
I thought a PDF tells you what the probability is for a certain value you put in.
My PDF says that between 1 and 2 the probabilty of getting a value inbetween this is
where y is the value you want to find the probability of getting it
BUT if you put a 2 in you get a probability greater than 1, which cant be
Two things :
- the probability that a continuous random variable takes a specific value is 0.
- if X has the pdf f, then :
, and not something like
A third thing... :
A function is a pdf if : it is a positive function, and its integral over is 1.
1. If Y is a continuous random variable, then Pr(Y = a) = 0. It only makes sense to talk about the probabilty that Y lies between two values. You do not calculate probabilities by substituting values of y into the pdf.
2. For , .
You are strongly advised to extensively review all you have learned on continuous random variables and probability density functions.