Im looking to create a distribution of maximum wind speed expected in a 10 year period, based upon the Australian wind code AS1170.2
ie, I want to be able to calculate the chance that say 30m/s wind speed is exceeded in the next 10 years.
The issue is, the only data it gives to work with to create this is a formula:
The wind speed that has a 10% chance of being exceeded in the next R years is: 122-104R^-0.1
I don't need a perfect answer, just something that is a reasonable approximation. ie, it doesnt really 35ms might be 45% or 55% to be exceeded is ok, but a 40-60% range is probably getting a little large
Related
So I am trying to find my average time in Excel and I have been using the average function but even though I do not know what the exact value should be I know that what was being returned was way off. So I googled Excel time format and followed the instructions and changed my time from MM:SS format to H:MM:SS format; because the article said that way I am guaranteed to get correct averages when I use Excel's native average function.
However, I am running Excels average function on mixed values like the below:
1:20:30
0:04:00
0:00:30
0:00:05
--------
Average: 0:21:16
Can someone just please share their expertise with me and verify that the above average calculation is correct that I obtained by just easily using Excel's native average function.
I just want to be sure before I change everything on my spreadsheet.
Working with times and their various formats/representations can be tricky in Excel - sometimes I convert to serial and then multiply by 24 to ascertain the number of hours in the day, other times not. In your case, this appears to be straight forward and can easily be verified.
Here/screenshot refer:
Mathematically: you can determine the number of hours, minutes, seconds directly from what you have using respective equations as follows:
=hour(E4)
=minute(E4)
=second(E4)
Determining the average is then a trivial exercise by summing and dividing by the count (4), which reconciles (as can be seen).
Let's apply logic too: average of 21 mins looks about right - consider equivalent scenario of average running time for 4 athletes, where one of them takes 80 mins and the others take under 5 each - average time will be around 20 mins (~80/4).
This may be more of a statistics question, and I'd like to find a solution with Excel. I'd rather use simple VBA if any coding is necessary.
Is there a way to estimate the percentile of a specific data point in a skewed distribution? I don't need exact percentiles and only need a reasonable estimate. I work on analyses that rely on weighted average benchmarks reported by multiple sources. All of my sources report the 25th, 50th, 75th, and 90th percentiles as well as the mean and standard deviation. We use these benchmarks to set a target range, and our goal is for our results from a specific analysis to land somewhere within the published percentiles. I'm often asked to indicate what percentile our specific result is at, and all I can provide is broad ranges like 25th-50th, etc. So, I'm then asked to use simple extrapolation to determine the specific percentile of the specific result, and I know that using this method is inaccurate.
Mean and median differ in 99% of cases in my data set, but % difference between mean and median on average is only 6%. Only about 10% of cases have mean and median with greater than 10% difference.
For the 90% of cases with relatively low % difference between mean and median, can I assume the normal distribution?
For cases with higher % difference between mean and median, can I make an assumption that will help me estimate more accurately? I could for these cases just use the normal distribution and send my percentile estimate along with a note indicating that the estimate is likely off in one direction or another, but I'd rather give a better estimate.
Responding to cybernetic.nomad:
First, thanks for commenting! Second, it doesn't seem to work. I think I don't have enough data. The attached image shows an example. The first 5 rows show one set of my weighted average benchmarks for a single case. Below that, I added two lines--one with my "target" amount. This could be any number but, to test out the formula you suggested, I entered my 50th percentile weighted average. The row below that has the results of the formula =percentrank.exc(25th:90th,target). The result should be 0.5 but it's not, so I don't think this works. example
I am trying to account the value of a certain amount of grain coming in and out of storage based on the amount of fees. The grain is stored in a lump sum. I am trying to calculate the value/tonne of outcoming grain utilising a first in first out type approach in Excel. I have attempted learning Python for this task but I feel like it will be a while before my ability utilising coding (something pretty foreign to me) will be at the level where I could perform this task.
For example 400 tonnes might come in at a certain value which starts accruing storage fees in May. Then in June there might be 500 tonnes come in and start accruing fees from there. In July I might decide to take 600 tonnes out of storage (obviously meaning that 400 tonnes worth of fees from June and 200 tonnes worth of fees from July). Doing this leaves 300 tonnes of grain still in storage accruing fees, spillover which is then accounted for first for the next calculation. The size of outtakes varies between being larger or smaller than the amount on intakes.
I have tried utilising a sort of mini-grid. Which implements a series of If checks to solve the issue but it's difficult to automate when an outtake requires multiple different intakes of grain (multiple rows in the column) to then go to the next untouched cell in that column after I've taken into account the "spillover" from the previous outtake.
Is there solution here that I'm missing, mainly around taking into account the differing amounts of cells required for a series of calculations?
I have set up an optimization problem but i must be doing something wrong and I could use your help. I have three firms: alpha, Bravo, Charlie. They each complete three tasks: Milling, Inspecting, Drilling. They each require different amounts of minutes to complete each task. Alpha requires 12 minutes to mill, 5 minutes to inspect and 10 minutes to drill. Bravo requires 10 minutes to mill, 4 to inspect, and 8 to drill. Charlie requires 8 to mill, 4 to inspect, and 16 to drill. After each firm completes all of these tasks they will earn a certain amount of profit, Alpha will earn $2.40, Bravo will earn $2.50, and Charlie will earn $3.00. All three firms have a maximum allotted time of 1200 minutes to mill, 900 to inspect, and 1440 to drill. The goal is to maximize the profit of these three firms. I have set it up so that the sums of the tasks will take away from the available time left when changed by the solver. I have also set constraints within the solver to cap each task to the allotted time allowed per task. I must be missing a vital step however because it keeps trying to just max out the allotted time for an individual firm, not taking in to account the opportunity cost of the other firms or something. Please help! (shown in photos)
Data
Solver
After executing Solver
I have changed the logic a bit different in order to take the minimum unit into consideration:
UNITS portion are the variable cells. Since the final produced unit will be the minimum of these cells, E9 formula is =MIN(B9:D9) and copied down.
TIME portion is multiplication of Unit Times and Units. So the formula of B14 is =B9*B2 and copied down & right.
I9:I11 are the earnings calculated by multiplying the unit earning with the minimum units
I12 is our total earning and is our Objective cell.
Please also be careful about the constraints since when you do not set an integer constrain, finding a solution becomes more difficult and of course our units should be integer in any case.
And also fill B9:D11 cells with some values such as 100, since otherwise iteration does not start correctly and solver ends up with a very small objective cell.
I have just had a go at this and I get a different answer as I have made the assumption that to achieve the profit the company must complete a milling process, then inspect, then drill and once all are complete then that is 1 unit for the profit - I hope that is valid.
But if not, then this layout may help you anyway. Note I have set this as a Linear model for the solver and also note the use of integer and non-negative.
It was fun anyway !
I'm trying to create a table in Excel which works out the overall average performance of a driver.
The layout of the table is below. You can see if the driver has had drops and has no early, late and OTIF then the total should show 100%.
But if the driver was to get an Early (for example) then this will affect the total percentage (it should go down from 100% to 90% for example). But i'm unsure on what formula to use in Excel? Any help / or tips would be very helpful!
Thank you.
So I am taking a guess here that the formula you want is:
=IFERROR((E4-(B4+C4+D4))/E4,"")
Clarity is needed on whether the Early, Late or OTIF numbers decrease the percentage by a fixed 10% each, or if it is just a percentage of the successful drops.
To find that number, the easiest way to do this is the following. (Note: I am assuming that the Drops column is indicating the total number of drops and not just the number of successful drops)
The best way to do this would be to take the total number of drops and subtract the number of undesirable outcomes from it. This creates the number of successful drops. Once that number is created, a simple division by the total number of drops will create the proper percentage. see below formula
=((E5-E2-E3-E4)/E4)
This should take the total number of successful drops and divide it by the total number of drops.
Hopefully, this helped! Good luck!