Posts

Should research funding be allocated at random?

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Earlier this week, a group of early-career scientists had an opportunity to quiz Jim Smith, Director of Science at the Wellcome Trust. The ECRs were attending a course on Advanced Methods for Reproducible Science that I ran with Chris Chambers and Marcus Munafo, and Jim kindly agreed to come along for an after-dinner session which started in a lecture room and ended in the bar. Among other things, he was asked about the demand for small-scale funding. In some areas of science, a grant of £20-30K could be very useful in enabling a scientist to employ an assistant to gather data, or to buy a key piece of equipment. Jim pointed out that from a funder’s perspective, small grants are not an attractive proposition, because the costs of administering them (finding reviewers, running grant panels, etc.) are high relative to the benefits they achieve. And it’s likely that there will be far more applicants for small grants. This made me wonder whether we might retain the benefits of small grants...

Improving reproducibility: the future is with the young

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I've recently had the pleasure of reviewing the applications to a course on Advanced Methods for Reproducible Science that I'm running in April together with Marcus Munafo and Chris Chambers.  We take a broad definition of 'Reproducibility' and cover not only ways to ensure that code and data are available for those who wish to reproduce experimental results, but also focus on how to design, analyse and pre-register studies to give replicable and generalisable findings. There is a strong sense of change in the air. Last year, most applicants were psychologists, even though we prioritised applications in biomedical sciences, as we are funded by the Biotechnology and Biological Sciences Research Council and European College of Neuropsychopharmacology. The sense was that issues of reproducibility were not not so high on the radar of disciplines outside psychology. This year things are different. We again attracted a fair number of psychologists, but we also have applicants...

Do you really want another referendum? Be careful what you wish for

Many people in my Twitter timeline have been calling for another referendum on Brexit. Since most of the people I follow regard Brexit as an unmitigated disaster, one can see they are desperate to adopt any measure that might stop it. Things have now got even more interesting with arch-Brexiteer, Nigel Farage, calling yesterday for another referendum. Unless he is playing a particularly complicated game, he presumably also thinks that his side will win – and with an increased majority that will ensure that Brexit is not disrupted. Let me be clear. I think Brexit is a disaster. But I really do not think another referendum is a good idea. If there's one thing that the last referendum demonstrated, it is that this is a terrible method for making political decisions on complicated issues. I'm well-educated and well-read, yet at the time of the referendum, I understood very little about how the EU worked. My main information came from newspapers and social media – including articles...

Using simulations to understand p-values

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Intuitive explanations of statistical concepts for novices #4 The p-value is widely used but widely misunderstood. I'll demonstrate this in the context of intervention studies. The key question is how confident can we be that an apparently beneficial effect of treatment reflects a change due to the intervention, rather than arising just through the play of chance. The p-value gives one way of deciding that. There are other approaches, including those based on Bayesian statistics, which are preferred by many statisticians. But I will focus here on the traditional null hypothesis significance testing (NHST) approach, which dominates statistical reporting in many areas of science, and which uses p-values. As illustrated in my previous blogpost , where our measures include random noise, the distorting effects of chance mean that we can never be certain whether or not a particular pattern of data reflects a real difference between groups. However, we can compute the probability that the...

Using simulations to understand the importance of sample size

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Intuitive explanations of statistical concepts for novices #3 I'll be focusing here on the kinds of stats needed if you conduct an intervention study. Suppose we measured the number of words children could define on a 20-word vocabulary task. Words were selected so that at the start of training, none of the children knew any of them. At the end of 3 months of training, every child in the vocabulary training group (B) knew four words, whereas those in a control group (A) knew three words. If we had 10 children per group, the plot of final scores would look like Figure 1 panel 1. Figure 1. Fictional data to demonstrate concept of random error (noise) In practice, intervention data never look like this. There is always unexplained variation in intervention outcomes, and real results look more like panel 2 or panel 3. That is, in each group, some children learn more than average and some less than average. Such fluctuations can reflect numerous sources of uncontrolled variation: for in...

Reproducibility and phonics: necessary but not sufficient

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Over a hotel breakfast at an unfeasibly early hour (I'm a clock mutant) I saw two things on Twitter that appeared totally unrelated but which captured my interest for similar reasons. The two topics were the phonics wars and the reproducibility crisis. For those of you who don't work on children's reading, the idea of phonics wars may seem weid. But sadly, there we have it: those in charge of the education of young minds locked in battle over how to teach children to read. Andrew Old (@oldandrewuk), an exasperated teacher, sounded off this week about 'phonics denialists', who are vehemently opposed to phonics instrution, despite a mountain of evidence indicating this is an important aspect of teaching children to read. He analysed three particular arguments used to defend an anti-phonics stance. I won't summarise the whole piece, as you can read what Andrew says in his blogpost . Rather, I just want to note one of the points that struck a chord with me. It'...

ANOVA, t-tests and regression: different ways of showing the same thing

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Intuitive explanations of statistical concepts for novices #2 In my last post , I gave a brief explainer of what the term 'Analysis of variance' actually means – essentially you are comparing how much variation in a measure is associated with a group effect and how much with within-group variation. The use of t-tests and ANOVA by psychologists is something of a historical artefact. These methods have been taught to generations of researchers in their basic statistics training, and they do the business for many basic experimental designs. Many statisticians, however, prefer variants of regression analysis. The point of this post is to explain that, if you are just comparing two groups, all three methods – ANOVA, t-test and linear regression – are equivalent. None of this is new but it is often confusing to beginners. Anyone learning basic statistics probably started out with the t-test. This is a simple way of comparing the means of two groups, and, just like ANOVA, it looks at...