Random Number Generator Based On Weibull Distribution
Sep 10, 2007
how to go about generating random numbers based on Weibull distribution in VBA? I had a rough idea for Normal (from link below) which i later extended to Lognormal but am having difficulty with Weibull and Gamma will appreciate any help.
Background Info: I am doing a weibull analysis on failure data. Some of the data is right censored. I have already run a maximum likelihood estimate to obtain the estimated weibull parameters with Excel's SOLVER function. I am good on this part.
Now I want to calculate these parameters with a 95% confidence interval. I can't seem to find information on calculating confidence intervals with right censored data.
I have a range of cells that have values from 1 to 7 in them. What I would like to do is to have the next column generate a random number from 1 to 7 that does not generate the number that the cell next to it has. for example if cell A1 has 6 in it, I would like cell b1 to generate a random number other than 6 in it. if cell A2 has 3 in it then cell B2 would generate a number other that 3 (1,2,4,5,6, and 7).
I have 4 names, and a grid of 100 boxes. I need those 4 names randomly deposited in the 100 boxes, making sure each name is displayed an equal number of times (25 each) Is there an Excel formula to compute this?
in VBA the RND function generates a random number using uniform distribution (every number is as likely as any other). Is there a function to generate a random number using normal distribution where the numbers closest to the mean are more likely to occure then numbers further away from the mean. I've created the following custom function to generate a random number between two given values using uniform distribution.
Function RandNum(Min As Double, Max As Double) As Double RandNum = (Max - Min) * Rnd + Min End Function
Sheet 1 A1 through A6 has STR, DEX, CON, INT, WIS and CHA. B1 through B6 is waiting for results from sheet 2.
Sheet 2 A1 is data validation of d4, d6, d8, d10, d12, d20 and d100. A2 through A7 are currently Rand formulae triggered by A1 with B1 adding number of dice (minimum 1) and B2 a modifier value add to the rolled result. D2 through D7 are data validation modifiers of -10 to +10 (0 included). E2 through E7 is the result of A2+C2. The Rand works fine, but every time data is changed Rand recalculates. I'm hoping for a macro executed by a button to generate six random numbers based on the chosen die value of A1 ranging from 1-4 to 1-100. The die roll can never be below 1 and no higher than the chosen die. I then want to transfer the result from E? To sheet 1 B1 to B6 matching its appropriate atribute. I named them Char01_STR, etc on sheet 1 A1 to A6.
I have a set of data with index numbers and the percentage of their occurrence. I want to use this percentage to weight the occurrence of the index numbers and create a random list of say 500 occurrences.
As you can see below, I've written code that writes random numbers into three columns of a spreadsheet (10 numbers in each column).
What I want to do is create code that will run the random number generator for a period of 1 minute and then stop. I know that I will need to write a timer subroutine to do this but I'm how unsure how to do this.
I am organizing a sports tournament and would like excel to randomly generate the teams for it.
We have 20 people who will be organized into 10 teams of two. how to setup the formula to have two people randomly paired together without duplication. The names will be further used in other formulas for points calculations.
So, I have the names as A1:A20 and then would like the teams generated from B1:B10 and C1:C10 with the team being the row and the team members in the B and C columns.
In column AB I have a list of 28 weeks written in date format.
In column B I'd like to chose one week from the 28 weeks listed in AB at random. But B2 - B9 can not have the same date (ie could not have two dates for the 19th of April).
How exactly is that done?
Alternatively - is it possible to have in Column AA the 8 team names. In Column AB the 28 weeks. In Column A a random team picked from column AA and in Column B a random date picked from Column AB. Both column A and Column B can not have duplicates... There's 28 weeks with 8 teams - therefore I only need 8 unique weeks.
Has anyone seen an Excel program that will generate words based on letters entered. For example, if I had 10 cells in a row, and each cell contained a letter (duplicates are okay), what words could be derived from arranging those letters in random sequences.
It would need the ability to accept any letter of the alphabet, A thru Z
E A L R C T S S U C ___ ___ ___ ___ ___ ___ ___ ___ ___ ___
How many words could it generate, and what are the words? I assume it would have to reference a spelling dictionary.
It could be used as a spelling learning game, etc.
I wrote this to help me generate a random password for a workbook. I am happy with it so far, but I was wondering if there is a way, to shuffle the order of the variables? So, instead of MyPassword always being A, B, C, D, E etc
Sub RandPass() Dim A As String, B As String, C As String Dim D As String, E As String, F As String Dim H As String, I As String, J As String Dim K As String, L As String, M As String Dim MyPassword As String Dim v
ReDim v(33 To 47) As Variant A = Chr(Int((UBound(v) - LBound(v) + 1) * Rnd + LBound(v)))..............
I have a spreadsheet which has a list of staff (column B) and work categories (row 3).
Row 4 is updated each day with a count of the incoming work for each work category.
I want to be able to randomly distribute (as evenly as possible) the no of work items in Row 4 between the doers (B7:B13). Each item of work also has to be checked so I would also like to randomly distribute the checking between the checkers (B16:B18)....
I need a formula to create random letters down a column: A-F. Probability of A=3%, B=6%, C=8%, D=11%, E=14%, F=16%. I've got it worked out to where each letter is a header of a column ("A" is in A1, "B" is in B1, etc.). My question is: how do I consolidate that in one column, so that, "A" for example, reads ABFCBACFBFBECEABCEABCEAFBCEFBCAFEBCFAEBFC...? I'm using the random number generator for the 6 columns...thx
I have a database of at least 350 products, and would like to know how I can use a form button, when clicked it will randomly display a picture of one of the list of products. I want to use this method for a mystery prize draw.