Last night saw a joint Sky News/News Ltd tabloid “town hall” style political shindig at the Rooty Hill RSL Club –  where Abbott and Gillard stated their case for election and answered questions from the floor.

There was a lot of debate about the bias or otherwise of the audience, where they appeared much tougher on Gillard than Abbott, and where people were identifying Young Liberals in an audience that was supposed to be filled with “uncommitted” voters.

However, the reality is a little more complicated and nuanced than is generally being described.

Galaxy was the pollster that ran the audience selection process, so it’s worth going through what they did. There were two components involved – a random phone component and an online panel component. Part of the audience was selected by the same methodology Galaxy uses for their  phone polls – ringing random households in the geographical footprint they were targeting (such as the whole country for national polls, states for state polls, local electorates for electorate level polling or, in this case, the area around Western Sydney).

Galaxy asked respondents if they had made up their mind on who they are going to vote for come next Saturday, and those respondents that said they had not made up their mind – that said they were undecided – then got the big tick. They were then asked if they’d be willing to participate in the Rumble in the Rissole. Some did – and turned up at Rooty Hill. Some declined and went about their life.

Galaxy also used their online panel to select audience members, by emailing people on their panel that lived in the targeted geographical footprint and asked them the same thing via email that they asked their phone respondents. Those that stated they hadn’t made up their mind on who they were voting for were then asked if they would participate at the event. Some did – and turned up at Rooty Hill. Some declined and went about their life.

What we need to remember here is that the brief was to get undecided voters. What is “undecided”? Well, it’s people that state they have yet to “decide” who they will vote for.

People will tell porkies to pollsters on their undecidedness for a whole variety of reasons – it’s a well recognised, worldwide phenomenon. One of the most famous examples of this occurs in the UK with what is known as the Shy Tory effect – where a significant number of conservative voters refuse to tell pollsters who they are intending to vote for, often by stating that they are undecided when, in fact, they are not.

Undecided doesn’t mean “a voter with no partisan alignment who has a demonstrated history of voting for both sides of politics”. That is a different group altogether –requiring a much more complicated, costly and time consuming screening process to identify.

Undecided simply means voters that haven’t decided – and the easiest way of determining that is, as with all other polling, simply to ask them.

So the audience at the Rumble in the Rissole was a group of self-identified undecided voters roughly balanced by gender and age – but that doesn’t mean they weren’t leaning, or didn’t have their own political predispositions or partisan gripes – we certainly witnessed some of that coming out last night. All it simply meant was that they had self-identified as undecideds on their voting intention.

That was the screen.

That’s what we got.

That’s what we saw.

There was no conspiracy, no deliberate skewing of the audience, no deliberate bias or stacking – just the results of a simple undecided screen . The audience looked and may well have had a lean toward Abbott, but we’ve seen the same thing happen in the opposite direction at other times, such as the worms and Polliegraphs from leaders debates.

Sometimes it leans one way a bit, sometimes it leans the other way a bit – sometimes it doesn’t at all. That’s the nature of the beast