Random Value Generation From Skewed Normal Distribution
Sep 20, 2008
I would like to generate a random value using a skewed normal distribution. For inputs I have the sample mean, standard deviation, and skewness. I would like to find a way to generate numbers randomly that would fit the skewed normal distribution described by the inputs.
Some information about skewed normal distributions can be found here: ...
i have some number that i want to put in a normal distribution
so.. i have age ( 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) and have the number of times that the kid wake in the night ( 10, 12, 9,11,8,9,7,9,11) and want to do the normal distribution grafic with that .
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
Say I measure the height of 1000 people and I have those in a column in excel. It should be a normal distribution with mean x and standard deviation y. How do I actually graph it so I can see the normal distrubution curve that looks something like this: [url]
I tried making a scatter graph but it graphs them point by point. I want the height to be on the x axis and something like frequency on the y axis.
I'm trying to make a bell curve (normal gauss distribution). I have some problems regarding the probability density curve, since its values are so low. If you look column N in the attached file - I used the NORMDIST command. Values should be somewhere between 0,2 and 0,4 - but they're about 100x lower.
I saw one of my classmates do quick normal distribution by the click of a button and when I asked her she said she used VBA function of Excel.
This is what I would like to do: Have a macro/VBA in one excel file. And using that excel file do normal distribution for an excel file that's opened in another window.
I have weird alpha value like 14.385%, a sample size (36). What is the corresponding critical value for the normal distribution. There are questions like this dealing with the Student T dist, Chi Squared and F distribution. If i can figure out how to do it for one I can probably do it for all of them.
I get the following error whenever I try running a Monte Carlo simulation with iterations in excess of 64000 (The MC simulation calls the 'NormSInv' worksheet function at least once per iteration, and the argument to the 'NormSInv' function is always a standard normal RANDOM number also generated by Excel VBA): Run-time error '1004': Unable to get the NormSInv property of the WorksheetFunction class Why do I inevitably encounter this error ONLY when the number of iterations exceeds 64000, for instance? Simulations with iterations < 64000 run smoothly without a glitch.
I understand how RAND and RANDBETWEEN work, but have a slightly more complicated random number generation problem that requires a number that isn't solely between two numbers.
I have one cell that is randomly generating a number between 0 and 350 (we'll call this value A) and another randomly generating a number between 0 and 15 (value B). Then, I have a third cell (value C) that equals 15 minus B. Where I am having trouble is with a fourth cell (value D). This cell I want to have randomly generate a number between 0 and 350 but it needs to be D less than the value in A or C more than the value in A. Is there an advanced random number generation technique that can solve this?
I have three columns A,B&C In the column A Iwill generate random numbers between 40&50, In the Column B I will generate random numbers between 35&45, The column C is the sum of Column A&B(i.e. C=A+B) but I the sum should be between 83&88. I need acondition such that the random numbers generated in Column A&B Should satisfy the Column C(A+B) condition sdatisfying the A&B columns condition.
I'm trying to write a code that will generate random numbers and no number appears more than onece.
For I = 0 To 3 For J = 0 To I Do n = Int(4 * Rnd) + 1 'random number generated Array1(I) = n 'random number settled in an array If (I = I - J) Then 'checking for the same place in array numsOK = True Else If Array1(I) = Array1(I - J) Then ' comparing two different places in an array numsOK = False Else numsOK = True End If End If
Been trying to think of a way to get random numbers 1 to 36 generated without repeating in the same column, however also getting it to perform the same opertaion in 9 more columns (B:J) without the same number appearing in the same row.
example
1 2 5 4 2 5 3 1 3 4 1 5 4 1 2 3 5 3 4 2
Unsure if this is possible, have created a basic script for random number generation but have no clue how to expand across columns.
But i want to save the number in a dim single variable called N. I try to put N where i have write ActiveSheet.Range("$B$2") and do N=Application.Run ... But it doesn't work.
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've managed to write a random number generator that produces multiple sets with no repeating numbers per a set.
Now, to step it up a notch, I'm trying to create an even distribution of the numbers generated which is where I could use a hand. Here's my current code:
Code: Option Base 1 Sub RandomNumberStrings() Dim rndno As String, strg As String, msg1 As String Dim r1() As String, r2() As String
[Code]....
Equaling 500 numbers generated as intended, but my target is to get every number with an equal frequency.
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.
I am working on a Random Cycle Count Generator that provides random SKU#s based on 3 separate columns of SKU listings. The user clicks a button to generate the SKU#s to cycle count for that day. What I would like to see is a date stamp in the columns next(B,D,F) to the referenced SKU listing(A,C,E) based on which SKU#s are generated. This will let me see the last date that the SKU was generated. I would also like it to automatically save after generating.
I have multiple users that use a spreadsheet to enter data. I am trying to figure a way to assign a case number to each row of data that is entered. I cannot really do sequential numbers, because often people are entering data at the same time, and often these people are working offline.
So I was thinking if I could somehow have the case number be a few letters (to identify a specific person) and then a series of numbers (to signify which case number it is). That would allow multiple users to enter data offline simultaneously without having to worry that the case numbers are going to be the same. Maybe I could use the Application.UserName and somehow parse it to give me the letters (perhaps Intials or something), and then somehow apply sequential numbers to that...
I m trying to achieve is generating ref numbers automatically.
I have attached an example.
In Cell A if the user choose yes it gives a ref number. The trouble im having is that say in cell A5 a Yes is choosen at a later date, it will throw the numbers out of order and the ref numbers get mixed up, there any way of stopping this from happening or any function that prevents this from happening
I have multiple files that I need to get data from. My dream is to push a button and gather the data from variable files. (I know how to make the button and get data from single file).
The file name is below:
Cell A1 contains this formula ='C:ReportsYear 2009[CityWaterReports Jan 2009.xls]PHFlows'!$B$44
Cell A2 contains this formula ='C:ReportsYear 2009[CityWaterReports Feb 2009.xls]PHFlows'!$B$44 and so on.
I would like the customer to be able to push the button and be asked to enter the year(eg: 2008) and have the formula update to the new year in each cell.
I have only two sheets..first sheet is the user sheet where the user gives the data...second is the sheet where in we get the result according to user given data..
there is a cell in User sheet where User gives a Number. for example " 8 "
so sheet2 : here we have only 9 rows. as user gave "8" the fisrt 8 cells in the first column should see like this
B 01/08 , B02/08 , B03/08 as so on till B08/08
when user gives 9 in user sheet
then the first sheet is finished with all the 9 rows ending with B09/08
when user gives 10...then sheet 3 should automatically appear with the first row and first colum saying B10/08.
when user gives 20 in user sheet...then sheet4 should appear with last number as B20/08
so each sheet is having only 9 rows..
first sheet ends with B09/08 second sheet ends with B18/08 third sheet ends with B27/08