Still Not Significant

There has been a lack of posting lately, mostly because a very busy marking schedule has caught up with me.

So I hope you will enjoy this link to ‘Probable Error’, which has spent a very likely significant amount of time rounding up all the ways scientists use to describe P values which aren’t anywhere near significant at all.

Given the paper I’m currently reviewing reporting a tendency of P=0.07, I was highly amused!

Probable Error

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What to do if your p-value is just over the arbitrary threshold for ‘significance’ of p=0.05?

You don’t need to play the significance testing game – there are better methods, like quoting the effect size with a confidence interval – but if you do, the rules are simple: the result is either significant or it isn’t.

So if your p-value remains stubbornly higher than 0.05, you should call it ‘non-significant’ and write it up as such. The problem for many authors is that this just isn’t the answer they were looking for: publishing so-called ‘negative results’ is harder than ‘positive results’.

The solution is to apply the time-honoured tactic of circumlocution to disguise the non-significant result as something more interesting. The following list is culled from peer-reviewed journal articles in which (a) the authors set themselves the threshold of 0.05 for significance, (b) failed to achieve that threshold value for…

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Chronicles of Athena – 42 Weeks

Oh the freedom you feel on a Sunday when you also have the Monday off. I am going to live the life of a short girl on the internet and hem some cute dresses and fix a seam on a kimono I got from a vintage shop. It’s all going to be very pinterest, with a little kitten sitting beside a sewing machine and a freshly made caramel latte (from a machine – I am the definition of bourgeois bohemian).

But of course, the photos I post to instagram will not fully represent what’s happening as I repeatedly shout “Athena! Theena! Drop it! Don’t eat that. Here have this.” and obsessively count glass headed pins and picture perforated intestines. But social media isn’t really for reality, is it?

Several people have commented lately that Athena appears to know her name. I’ve been meditating on this from a scientific point of view. You can certainly catch Athena’s attention with her name, or the ‘Theenie/Theena’ variants of it. But does she know that those words specifically mean ‘small fluffy thing that is me’, or do they mean ‘there might be food or toys or love over there’, or more simply ‘pay attention now’.

But she also has certain chirrups that I fancy mean ‘mum’ or at the least ‘two legged cat who feeds me’. Even if it just means ‘pay attention now’, it gets the job done, right?

Somehow, with different brain structures, an evolutionary history giving us very different social structures, Athena and I can reliably draw one another’s attention with certain vocalisations. Pets are freaky.

Implicit Bias – Representation Matters

Our tea breaks (and a certain someone’s 30th birthday) last week was abuzz about a seminar we got from @fatwhitebloke who was talking about implicit bias.

STEM has a problem with women, and the UK in general has a problem with immigrants, so the talk was very relevant to us. Dr Jones was talking to us about implicit bias, and how our subconscious mind makes decisions that our conscious minds would not. Jones was very explicit about his own implicit biases, which I appreciated. Having a bias does not make you a bad person, but allowing that bias to control your decisions, and being unwilling to change that, does.

They have a little youtube vid about it here:

But one of the things Jones said really stuck out to me, because I spend a lot of time on places like Tumblr and seeing ‘representation matters‘. I ‘know’ this on an instinctive level, I know that Gadget and Captain Janeway are part of the reason I’m here today. When I was little, I identified with the women, and I know that I’m very happy with my life and where I’ve ended. Representation matters to me.

But I’d never thought of it as Dr Jones explained it – and he did this off the cuff, noting to us that this one audience where he didn’t need to explain ‘mylenation of the neurons’.

It certainly sparked some of mine.

You know that electricity is messy. You may have seen electricity jump before (though perhaps not so spectacularly), and you know that electrical wires must be insulated with plastic. Our brains are collections of neurons, a kind of cell that can transmit electrical energy – just like a wire. When babies are young, unable to walk, or to coordinate their movements, all these neurons are ‘firing’ and the electricity is going everywhere. The important neurons coordinating where hands go need to be insulated to keep that signal going along the right path, so with us, those neurons become insulated with a fatty sheath that does not conduct electricity. We call this myelination.

Important pathways in the brain (like the parts that help you to touch your finger to your nose) get well insulated.

Jones asked us to imagine we were walking into an office and we saw the receptionist – who is the receptionist? What are they wearing? How do they compose themselves? Don’t cheat – like most of us you probably saw an attractive (white?) woman, well (sexily?) dressed. It’s how we see secretaries in the media, it’s not necessarily what we know of secretaries from our own personal experience. And our conscious mind doesn’t believe it, but our conscious mind often passes off those decisions to the part of our mind that made all of those connections.

And when you reinforced those connections, what happened? The more we see that, the more those connections get insulated. They become easier to reach next time, and the time after that, and the time after that. And then as we get older, they become our go-to position.

Now there might be one more argument here – that  hey, perhaps a lot of secretaries ARE sexily dressed white women so what’s the problem?

Here we have two choices. This person is a secretary. This person is a secretary who is a sexy woman. Most people will choose the second option with more detail, because humans are terrible at probability. We see that extra information and say “yes, that fits with what I think about secretaries”, forgetting that the subpopulation of sexy female secretaries will ALWAYS be smaller than the larger population just described by ‘secretary’. (See the io9 post on the fallacy here).

Our implicit biases make assumptions and decisions for us. Representation matters because it can stop the insulation of the connections – it makes us less likely to jump to that conclusion. Which leads me to the amazing Guillermo del Toro quote:

I think that every choice is political. When you decide that a woman can be a character of her own and not have to fall in love with the f***ing guy, that’s a political choice. When you choose that they can speak in their own language and be subtitled, that’s a political choice. I think it’s very important for us to understand that we are all — the whole world — in the same robot. It’s this f***ing planet. No matter who you are, what you like to do, whatever your race or whatever your religion, we’re all human. And I think it’s really great to make a movie that celebrates that diversity.

So yes, representation matters. And science agrees.

Chronicles of Athena – 41 Weeks

I’m the kind of person who likes rules (rules control the fun) so Athena should take it as a little victory that she broke me this week.

You see, Athena is a fussy eater.  Athena likes dry food, and treats. Athena will tolerate poultry based foods if it’s grilled and lightly covered in jelly (‘meaty chunks’ are not appropriate, and the richness of gravy based foods gives Athena what we will delicately call ‘the runs’ in large quantities). She will just about accept salmon or sardine if she’s hungry. She won’t eat cod or tuna regardless of how it’s prepared. She won’t even take mackerel off my plate, and if I’m eating salad she’ll try to steal a rocket leaf instead of a piece of a crab.

All of this means that of the range of kitten food available (which the box says ‘feed up until 1 year), there’s only one box where she will reliably eat about 75% of the sachets. For months now, when browsing the shelves I’ve been eyeing up one of the adult boxes of cat food, grilled, with jelly, chicken, turkey, duck, lamb and beef flavours. Just think, I would tell myself. Come July, I’ll be able to buy that box, and my one year old kitten would eat everything I put in front of her.

Well this month, after accidentally picking up a non-grilled box of food that contained BOTH tuna and cod (Athena is so against cod that she won’t even ask for more food when it’s on her plate for fear she might get cod again), I gave up and bought the grown up box 12 weeks early.

Thankfully, Athena didn’t immediately die from being given the wrong kind of food, so that’s a plus. She’s also added beef to her repertoire of nice things to eat.

Although she still has a day or so a week where she’d prefer not to eat. I have no idea where she gets this from. I’ve been on the 5:2 fad diet since Christmas and I still want to kill people when I’m stuffing my face with salad and pickle. Athena daintily turns her nose up and says “No thank you, I’m not hungry today”

Little bitch.

Teaching to Pass the Exam

When I was at school, I was taught to pass exams.

This is viewed very critically in the press – just take a look at these Google returns. But this is not the education I recognise in myself. From day 1 in my education, I was taught how to answer questions, how to tease a question apart into its component pieces (back in my day it was Knowledge & Understanding and Skills & Problem Solving, and every question featured both components).

I was taught how to game marking schemes, how to exploit a question’s structure to give me the most to talk about, how to use my skills when my knowledge failed me.

In news reports, we often hear that ‘teaching to pass exams’ means that university lecturers are having to re-teach the basics.

I never learned grammar at school – that might be obvious. I did poorly in the classes that drilled me on facts (I still only remember the first line of the German definitive articles, der, die, das, der, despite staring at the poster for two years straight). Even now, I ‘know’ the answer to very little. I don’t remember how many dairy cows are in the UK, or what her average milk yield is. That knowledge I outsource to Google. If you wanted a critical evaluation of dairy trends, I have the skills to deliver that, very quickly.

You might say my education was ‘curriculum led’ versus ‘item-teaching’, where I learned a subject thoroughly instead of being taught what was coming up in the test. I don’t think this is entirely true to be honest. My Highers (the big Scottish high school exam) were done way back in 2003. To prepare for my History exam, I tried my hand at answering the questions on the time frames I hadn’t been taught. I passed them. Not well, but I did pass. There was enough Skill and Problem Solving demonstrated to pass the answers.

I rely on those old exam techniques a lot as an academic. I don’t want to beat my breast and say that students aren’t being taught right any more – but I will say there the skills animal behaviour and welfare science uses to interrogate a question are not so different from the skills an English student will use to critique a piece of work, or a History student to draw up some conclusions. Animal behaviour and welfare is a science that demands a lot of evaluative thought alongside its experimental design.

And that’s not easy to teach

Chronicles of Athena – 40 Weeks

This week a man came into the house and played about with Athena’s favourite window. He even stood on her beautiful window sill with his boots on. I am sure you can imagine just how upset she was by the whole event.

Our new flat has the most beautiful light and I couldn’t resist taking advantage of it yesterday to demonstrate a cool little quirk of feline physiology. You might have seen this demonstrated on the BBC’s wonderful ‘Secret Life of Cats‘ but hopefully this video will show you how you can demonstrate this as a teacher or parent (or just to other people if you have a cat on hand!)

Watch how, despite no change in the light levels, Athena’s pupil size changes drastically before she pounces on Mr Ducky. She opens her pupils as wide as she can before pouncing so she can take in as much information as possible. It’s very obvious once you start looking for it, and would supplement a lesson on the physiology of the eye really well.

 

 

Animal science and behaviour science isn’t always easy to demonstrate, unlike chemistry or physics where you can set up experiments with a lot of household objects. I keep meaning to collect small examples of animal behaviour that work like this, so if you think this  kind of thing is useful, do let me know.