If you:
.xlsx
file)Then:
Each of the cells the result depends on corresponds to a variable (or 'node') in our calculation. For each variable, you can optionally supply a name and/or a probability distribution. This information must be given in the cells to the left and right of the variable cell.
Input probability distributions must be specified in the columns to the right.
The first cell to the right contains a string for the distribution family. This should be left blank for a deterministic variable. Options are:
Family | Quantiles | Notes | |||||
---|---|---|---|---|---|---|---|
Normal |
mean |
std |
2 | ||||
LogNormal |
mu |
sigma |
2 | Be careful, mu and sigma are not the mean and standard deviation of the distribution. |
|||
Uniform |
a |
b |
2 | a need not be less than b |
|||
PERT |
min |
mode |
max |
[lambda] |
Like the triangular, but a smoother shape (Wikipedia) The optional parameter lambda (default: 4) controls the weight given to the mode. Values of lambda < 4 have the effect of flattening the density curve. |
||
Beta |
alpha |
beta |
2 | ||||
LogUniform |
a |
b |
2 | a need not be less than b |
|||
Bernoulli |
p |
||||||
Discrete |
x_1 |
p_1 |
x_2 |
p_2 |
... | Generic discrete distribution over any finite set of values | |
TwoPieceUniform |
min |
sep |
max |
[psep] |
A piecewise uniform distribution with two pieces: a left piece from min to sep , and a right piece from sep to max .By default, each piece has 0.5 probability mass. If the optional parameter psep is supplied, it controls the probability of the left piece, i.e. the value of the CDF at sep . |
The family is not case-sensitive.
A distribution's parameters can be specified in one of two ways: explicitly as parameters, or via quantiles.
To the right of the distribution family, the next 1 or more columns specify the quantiles. The expected format is as follows:
p
followed by 1 or 2 digits representing integer percentiles between 0 and 100. For example: p5
, p05
, or p42
.n
-parameter distribution must have exactly n
quantiles. The CDF will pass through these quantiles exactly.To the right of the quantiles (if any) the next 1 or more columns specify the distribution parameters directly. No column headers are expected (since the parameters in question are different for each distribution family). The parameters are interpreted based on their order (i.e. as positional arguments).
The name of a variable is in the column to the left
The URL field accepts any URL to a publicly accessible .xlsx
file.
For your convenience, if a Google Sheets or OneDrive (Microsoft 365) URL is provided, we attempt to understand the URL and download the .xlsx
file from the provider (so you don't need to link to where the .xlsx
file is actually hosted).
Remember, if you create a new spreadsheet on Google Sheets or OneDrive, you need change sharing permissions so that Dagger can view it (to at least "anyone with the link can view").