# probability density

1. ### Average passanger waiting time - probability density function - normal distribution

Hello guys, so we got this additional task to solve for a post-modul at university: - The intermediate arrival time of a bus is normal distributed - The expected value of the intermediate arrival time during rush hour is 4 minutes - The standard deviation of the intermediate arrival time is 50...
2. ### probability density

Hi All I am currently doing Master in data science. I came across the function PDF probability density function which is used to find cumulative probability(range) of a continuous random variable. The PDF probability density function is plotted against probability density in y axis...
3. ### Exponential Distribution Problem

Hi! I am doing a problem using the exponential distribution function, but I'm having trouble understanding iii. There was a typo and the answer for iii is actually e^-4lambda, but I still don't understand how i'd get there. I think I have to use conditional probability but even then I'm not...
4. ### Different solutions when using direct calculation and Chebychev's inequality

Hi all, I have a question that I can't find answer to: I have 10 random variables X1, X2....X10 which are all independent and exponentially distributed with parameter=2 Xi~exp(2) for i between 1 and 10. Now the argument says that the probability that the sum of all 10 X's is larger...
5. ### Kernel Density Outlier Threshold

Hi All, First of all, thanks for showing an interest in this thread, and secondly, if your so kind to give your thoughts, I'd be so grateful. Background - We work with financial bank statements for fraud investigation. - I have converted a bank statements debit transactions into a scatter...
6. ### Name of distribution with density proportional to incomplete gamma function

Hi, Does anyone know the name of the probability distribution with the following density function? f_X(x)=\frac{\Gamma[\alpha,x]}{\Gamma[\alpha+1]}, where x>0, \alpha>0, \Gamma[\alpha,x] is an upper incomplete gamma function, and \Gamma[\alpha] is a gamma function. I occasionally...
7. ### Seemingly unsolvable conditional probability

The following is a question that is likely to be appear on my exam on Friday (tomorrow) but contextualised into a different scenario. I'm having serious difficulty figuring out how to go about answering it. If anybody has encountered something similar and could provide a step by step explanation...
8. ### Finding the Z-Score for Safety Stock Calculations

Dear Forum, I want to calculate the safety stocks required by our company to achieve a certain service level for our customers. The basic literature around this topic is quite clear: • Find the Standard Deviation of the Demand (expressed in weeks of demand in my case) • Define the service...
9. ### How to calculate the probability between two normal distributions?

Using the normal distribution. Let X  N(1, 2) and Y  N(2, 3) where N(μ, variance) denotes the normal distribution with mean μ and variance . X and Y are independent. Let U = 2X + 3Y . What is the mean of U? What is the variance of U? What is P(6<=U<=7.5)? What is P(X>Y)?
10. ### Multivariate probability density and distance... help!!

Hi all. I'm far from a stats connoisseur, and will probably use all the wrong words and describe my problem poorly. But I've got to figure it out and literally any help or direction would be greatly appreciated. I've got a set of observations, each consisting of seven two-dimensional...