It's only a 50/50 split if the pricing is evenly distributed across all possible values. My belief is that most prices that are not already on a 10c boundary would strongly favour the 'round up' option, being x.x9 x.x8 or x.x5. I don't have data to support that however.
It seems they are not 'rounding prices', but 'changing to round prices' - not quite the same thing underneath the marketing doublespeak - the woolies buying bloke quoted in the linked article says this:
The prices are not all rounded up or rounded down, it's about hitting the right number
So if my jar of Sauerkraut was 2.99, it might now be 3.50, if thats the "right number" they want to "hit". Interestingly of the 5 products they currently offer of the pickled cabbage persuasion, two are 3.00 even, one is 2.99, one 3.29 and one 3.38, none of which would round down ... Kransky is similar, one at 8.00 per kilo (deli) but of the pre-packaged (per pack) they are 6.49, 6.49 and 7.39. But I think we've worked out that they aren't 'rounding up/down' - looking at their online site now at various products it looks as though many have been changed already - also from the linked article:
Woolworths has already moved to round prices on its most popular fresh and dry grocery items, with its latest catalogue featuring only a handful of prices ending in 99¢ or 95¢.
So they are just changing to round prices - any prices that are effectively rounded based on the start and finish price seem to be just coincidence ??
Coles are doing it as well:
Coles also appears to have moved to a round or whole pricing strategy with its latest catalogue featuring only a small number of products with prices not ending in zero.
But the Germans aren't fooled, they're still going to use all the numbers
German discount giant Aldi hasn't jumped on the round pricing bandwagon, with its latest online catalogue full of prices ending in 99¢, 49¢ or 29¢ but it could be forced to change that, particularly if the five cent coin slips out of circulation.
So Aldi's Sauerkraut and Kransky will remain as is ...