Statistical goldmine !

Some years ago, it was possible to download (for free) a comprensive statistical text from www.statsoft.com .  It was great, just sat on my desktop until I needed it.

These days, you can get the same thing as an online resource, again for free http://www.statsoft.com/textbook/ .

I’ve just been made aware of something that is arguably as good, if not better http://surveyanalysis.org .

Whilst still under development, it already contains a massive amount of information, of interest to anyone who works in the advanced analytics area.

I recommend it strongly, and I can assure you that it is written by one of the smartest people I know.

Round the twist

Weirdly, I have found this post http://alandgraf.blogspot.com.au/2012/06/rounding-in-r.html to be fascinating. Maybe I need to get out more?

That blog post deals with how to round up (or down) when you have a number that isn’t a whole number.

For example, if you have an observation or data point that is equal to 4.5 and you want to use only whole numbers in your analysis, should you round down to 4 or up to 5?

It appears that there is no hard and fast rule for doing this; some argue for down and some for up. Similarly, some software rounds down in this instance and some up.

There is actually an international standard that applies; ISO/IEC/IEEE 60559:2011 which is identical to the IEEE Standard for Floating-Point Arithmetic (IEEE 754) established in 1985. [ISO/IEC/IEEE 60559:2011 covers a zillion other aspects of numerical computing and took seven years to produce.]

In relation to the above rounding issue, ISO/IEC/IEEE 60559:2011 apparently says, in effect:

“… round numbers ending in "1, 2, 3, and 4" down, and numbers that end in "6, 7, 8, 9" up. Then, specifically regarding "5", if the preceding digit is odd, round up and if the preceding digit is even, round down.”

The advantage of this is that 50% of the numbers will be rounded up, and 50% rounded down, instead of rounding up 5/9th's of the time, and so introducing a bias.

As one statistician (and a much better one than I am) I asked about this confirmed “…the clever thing about rounding to evens is that the average is not biased when this is done.”

I don't want your help, I just need your advice ...

Some of you will know of the hilarious late 80’s spoken piece by Fred Dagg (aka John Clarke), in which he ‘translated’ real-estate agent speak.  Here’s a short extract:

‘Owner transferred - reluctantly instructs us to sell’ means that the house is for sale.

‘Genuine reason for selling’ means that the house is for sale.

‘Rarely can we offer …’ means that the house is for sale.

‘Superbly presented delightful charmer’ doesn’t mean anything really, but it’s probably still for sale.

‘Most attractive immaculate home of character in prime dress-circle position’ means that the thing that’s for sale is a house.

There is lots more from Dagg/Clarke, of the same ilk.

My experience is that there are almost direct parallels in our own businesses, e.g.

‘I just need to pick your brain’ means that I want you to give/tell me something for free, on the basis of your extensive experience and knowledge that you have spent many, many years acquiring.

‘I have an interesting challenge for you’  means that I want you to give/tell me something for free etc.

‘I wonder if you could come in for a meeting and help us sort out what we need to do’ means that I want you to take 2 or 3 hours out of your day and give/tell me something for free etc.

‘Quick question’ means that I am going to ask you something complicated that you will need to think about for a while, and I want you to do it for free.

‘Exciting new project’ means that I need your input for our proposal, and I don’t want to pay for it.

And probably the best of all (and I am not making this up) ….

‘I don't want your help, I just need your advice’ !!

Now, before you write me off as just another grumpy researcher (which isn’t actually too far from truth), please be assured that I almost invariably do respond positively to requests like the above.  I estimate that it takes me up to around an hour per week.  That’s around 50 hours per year, or a week-and-a-half per year that I could otherwise spend on project work/going to the beach/walking in the park/<insert your own words here>.

And I am the first to admit that I can myself be guilty of exactly the same sin, that is, phoning up a contact and asking for some free advice/input … but maybe that’s the payback: I help others, and someone else helps me?

It’s a fine line … and I know this general area has also been a hot topic amongst the IRG’ers (AMSRS’s Independent Research Group) in the recent past, admittedly more in the context of “We’ve commissioned you to do X, and we now want to add Y to the project, but we don’t want to pay any more, because there will be more work for you down the track”.

So where does one draw the line.  Indeed, should one draw the line?  Or is it simply a case of  ‘you scratch my back, and I’ll scratch yours’?