I have some additional comments to my previous post.

If we perform some calculation inside R, e.g.
> x <- fisher.test(matrix(c(60,40,70,30),2))

We assigned the results to the object 'x'. Now we can access various elements of x as follows:

1. How many elemts are stored inside x?
> length(x)
[1]  7

2. What are the names of those variables?
> y <- names(x)
> y
[1] "p.value"     "conf.int"    "estimate"    "null.value"  "alternative"
[6] "method"      "data.name"

This command has created an array (= y) with the names of the variables! We can get an individual name with y[[1]] (y[1] works as well).

3. How do we access the stored output by variable?
 - either iterate through x[[1]] -> to x[[length(x)]]
 > x[[i]]
 - OR iterate i = 1 to length(x), with
 > x[[y[[i]]]]

 - for subarrays, like x[[2]], we can apply the same thing one more time:
> length(x[[2]])
[1] 2
(x[[2]] is the 95% confidence interval for the OddsRatio, so it has an upper and a lower limit)
> x[[2]][1]        // for first value = lower limit
[1] 0.8317144

> x[[2]][2]        // for second value = upper limit
[1] 2.918995

CONCLUSIONS
============
A.) For statistical functions/techniques that return primarily a p-value, we can easily detect this, as one of the names will be "p.value" (it is usually the first element in the array, aka x[[1]]).

B.) We can import the data from R back into Calc, and create a list with the names of the variables from the output (aka names(x) ) AND let the more advanced user choose which variable from this list to enter into a Calc cell.

Well, hope this helps to overcome some of the obstacles.

Sincerely,

Leonard


Leonard Mada wrote:
Hi Wojciech,

I just read (http://www.utsc.utoronto.ca/~04grycwo/overview.pdf) and began thinking on your ideas.

Basically you are right, we need both methods: for advanced users and for beginners. That's my point, too.

Regarding your concerns with importing the R-output back into Calc, I do admit that there are some problems and issues to discuss. I will try to think of the best solution.

Until then, I can give you some useful tips:

1. lets say we perform some calculations in R and store the output in a new variable, e.g.
   x <- fisher.test(matrix(c(40,60,30,70),2))
   then we can get the output by typing at the prompt:> x
    OR
   we can get the length of the return object:
    :> length(x)
    <output> 7
and get every element individually from this output: (iterate through x[[1]] -> x[[7]] )
   :> x[[1]]
   <output>> [1] 0.1819324 (this is the p-value)

2. I imagine statistical functions as belonging to 2 large groups (this is NOT necessarily accurate BUT useful here):
   a.) those that report a p-value as the main result
        - this is usually the first value (aka x[[1]])
b.) those that perform more complex actions, like a multivariate model, or a resampling, or graphic

These latter functions will be more difficult to deal with. But lets stick now to the first group.

Hope this is helpful. I will try to work up a solution for the rest.

Sincerely,

Leonard

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