Monday, September 8, 2008

Why bother?

Why bother with Excel?

I mean, what's the point of doing all this programming crap? Why don't I just print a bunch of surveys, let my subjects fill them out, then I'll enter and code them?

Well, you can. But a bit of work now saves you lots of time later. And once you become familiar with the basics, not even the initial work will daunt you.

I have three main reasons why I prefer running surveys on Excel VBA:

(1) Control

The most beautiful thing about using VBA is the control you can have over your study.

My doctoral study involved two parts, first a task which contains the experimental manipulation, then the dependent response. As a general rule, I cannot let subjects see the dependent response until they have gone through the manipulation. I usually have 10 subjects per session. Now, no two people would ever complete the manipulation task at the same time, much less 10.

Had I used paper-and-pencil method, I would have to check on everyone's progress, hand out the dependent response when someone's finished, record their ID number (to make sure the two tasks match each other), put the papers into a sensible pile, etc etc. If 2-3 subjects finish the manipulation at the same time, I'd be stuffed. If one more ask me a curly question or two, the whole session would be in chaos.

What made it worse was that part of my manipulation task consisted of a number of survey questions - 180 of them to be precise. They all need to be counterbalanced. I wasn't going to print 180 different versions just for the sake of counterbalancing!

And of course, the keystone of experimental research - random assignment. I ran a 2x4 design, and for each condition, I had to hand out the manipulation and dependent measures in a different order. Maybe my memory is fish-like, but it's a pain remembering who is supposed to be in which condition! Wish I could have just pressed a button on the desk and all the right manipulation would just magically appear! ... wait, you can.

Excel VBA lets you control how your information is presented. Don't let subjects see certain material prematurely? Sure. Randomise a bunch of material? Try a few thousands of them. And response-dependent presentation of stimulus? A breeze.

Experimental studies demand control. That's what Excel VBA can do for you.

(2) Adaptability

Okay, I printed my aforementioned 180 versions of the same survey for my anticipated 400 subjects. My supervisor rings me up, "Alex, don't use the word 'satisfaction', say 'happy' in your survey". Oops. Early morning dash to the Faculty, change the survey (all 180 versions of them), frentic printing, feeling guilty for the trees as you pulp the 400 surveys...

With a well-designed VBA program, you can change everything with just a few clicks. You can still enjoy your 7am coffee at the coffee shop rather than frentically printing.

You might wish to run follow-up studies. Rather than ruining a few more soccer fields worth of trees, you can make easy minor adjustments. Or major ones.

(3) Speed

Surveys and experiments are time-consuming processes. Anything that helps you save time during and after studies are a beautiful thing.

I've lost countless hours just inputting
and coding survey responses into Excel. 7-point Likert scales I can deal with; what about continuous scales where subjects just put a dash on a line? The ruler and I became unlikely companions for some long evenings, converting millimetres into numbers, and into Excel.

Why not just record everything on Excel in the first place?!

Excel VBA not only helps you achieve quick data coding, but also enhances data collection speed. You can give the same program to as many subjects as you want, simultaneously. Why be stuck with sessions with only 4-5 respondents when you can hold 30-40 of them at once? Could save you days, even weeks, in data collection time. Spend that time do some useful work that could get you an extra publication, get noticed by the boss, play some golf - anything beats data-collection and data-entry.

My next blurb will be more useful and less lyrical in compliments, hopefully.

Stay a step ahead,
Alex.

1 comment:

Micheal Reynolds said...

kudos to the way u expressed the importance of vba
Might use it in my sales pitch !