Lefties are getting het up about the portrayal of benefit recipients in Channel 4's Benefits Street. I fear, though, that everyone is missing a point here - that even good current affairs programming is biased.

I don't say this because of any conspiracy theory, but rather because there's a disjoint between human interest stories and the truth.

Let's start from a basic fact - that in the social sciences, pretty much anything is true sometimes. A lot of political debate is therefore about quantifiers: do we mean a few, some, most or what? Social phenomena lie on a curve; the question is: what shape is that curve? Sure, some benefit recipients are "scroungers", but some are folk who've paid in all their lives and suffered bad luck. The question is: what are their respective numbers?

This, though, is a matter of statistics. But stats are dry and boring, and never as memorable as good human interest stories; Tim Harford tries heroically to rectify this, but I suspect his audience is small. This is why the public are horribly wrong about basic social statistics.

Good TV programmes, though, are about human interest, not lectures in statistics. And this means even good programmes can be misleading. Channel 4 might think it fair and balanced to show a "scrounger" alongside a "deserving" recipient - but doing so isn't so balanced if the latter outnumber the former 10 to one. There are a couple of other dangerous biases involved too:

- If the scrounger is a charismatic figure, he'll loom larger in our memories than a less charismatic "deserving" person. The availablity heuristic will then lead us to over-estimate the number of "scroungers".

- We get more angry about injustices inflicted upon us than upon other people. Seeing a scrounger thus makes us angrier than seeing a genuine victim of poverty, and this too leaves a more vivid impression. (The issue here isn't the financial cost of "scrounging" which is small, but rather the sense that a norm of reciprocity is being violated).

However, there is nothing odd about what Channel 4 is doing here. There are numerous other ways in which the news and current affairs reporting can warp our perspectives.

- "Woman murdered" is news, "60 million not murdered" is truth. Reporting can thus increase the fear of crime beyond what its prevalence deserves.

- "Hundreds killed in factory collapse is news", "tens of thousands killed by poverty is not. The benefits of industrialization and globalization are thus under-weighted.

- In reflecting political opinion, journalism helps to maintain the Overton window by excluding reasonable but minority views. How often do you hear market socialist or genuinely libertarian/anarchist ideas?

- "Row", "split", "clash", "crisis" are journalese. Mild disagreement and indifference are not. The significance of most events is thus exaggerated.

- The mere act of communicating with someone encourages them to become more generous towards us. The fact that empty suits are always on the TV and radio thus generates sympathy towards them, whilst the exclusion of the poor from the media encourages hard-heartedness towards them.

My point here is a simple one. You cannot reasonably expect the media to promote the truth, so we should not base our political opinions upon news and current affairs programmes. Lefties should regard the media not as a reason for anger, but rather as an illustration of the subtle ways in which ideology is propagated.