• Statistics

    Choosing a statistical test: A cheat sheet

    Students who are new to statistics tend to find it tricky to remember which test to use under which circumstances. The following diagram is intended as a decision aid only. There are many many more statistical tests that are not shown here, but these are the basic ones most commonly taught on psychology courses. Even if you end up finding out that you need a more complex or niche statistical test, an aide memoire like this can still be useful if it reminds of the relevant keywords to search. Remember, always check the assumptions of the test you choose.

  • Statistics

    Alternatives to pro-rating for missing data

    Behavioural scientists often collect data using multi-item measures of latent constructs. For instance, clinical psychologists measure anxiety and depression using self-report questionnaires composed of multiple psychometric items, whilst child psychologists measure developmental progress by asking parents batteries of questions. Missing data are extremely common on such questionnaires, and one usually finds that data are missing at the item level. In other words, participants miss out items, either by accident, or because they don’t want to answer certain questions. Thus, researchers are left with some data relating to a given construct for a particular participant, but not complete data. The usual solution is pro-rating, where the mean of the completed items…

  • All posts,  Self development

    Finding meaning in life

    What do humans need to be happy in life? The argument has sparked numerous debates for centuries. Some have argued that we can be happy so long as our basic needs for food and shelter and social connection are taken care of. Others have argued that we can be happy even in the face of indescribable suffering so long as we know how to control and guide our own minds. Over the last 70 years, more and more psychotherapists have come to the conclusion that human beings cannot be happy without a sense of meaning in life. I think this goes too far. Meaning is only one of the paths to happiness.…

  • All posts,  Statistics

    Computing variables and pro-rating in SPSS

    The basics SPSS allows you to compute new variables, based on existing ones. This is really useful if, for instance, you want to create a total score for a psychometric scale or other questionnaire. ⚠️ Be sure to read this post on assumption checks you should perform. You access the Compute Variable dialogue box from the Transform menu… Here’s what each part of the window is for… Now let’s say that you want to simply add up three variables to make a total score. You just need to type a sensible name in the left-hand column, and then pace each of the variables in the right-hand ‘Numeric Expression’ box, with…

  • All posts,  Self development

    Arguing with the universe

    Social media provide a strange playground for a psychologist. You get to watch people interacting, like a fly on the wall, much less intrusively than in real life. Each platform has its idiosyncrasies. Facebook ‘friendships’ mostly follow real-life ones, whilst Twitter and Reddit are dominated by relationships that exist only in cyberspace. Over the last couple of years, people have become more and more worried that these media may be causing or exacerbating a social divide. For example, in the political sphere, the centre-right and centre-left voices are being drowned out by the far-left and far-right. Numerous scholars and commentators have blamed social media. There might be some truth to…

  • Self development

    Enough information already

    “If [more] information was the answer, then we’d all be billionaires with perfect abs.” — Derek Sivers Thinking about a problem can often feel the same as dealing with it. This can be a dangerous psychological effect, which threatens to undermine your attempts at self-improvement. Behavioural scientists have published dozens of studies on this over the last two decades. Let’s take a moment to see how it works. When we say we are ‘thinking’ we mean we’re dealing with the world symbolically. We might be doing it purely in our heads, we might have the support of a piece of paper or a computer screen, but the information in our…

  • All posts,  Self development

    Opportunity cost

    Our wonderful, complex, modern world provides myriad opportunities. And so, of course, it presents us with many thousands of choices to make, and just as many opportunity costs. Unlike 99% of everyone who ever lived on this planet, you can take a glowing rectangle out of your pocket, tap it a few times, and have food delivered to your home within a day or two. We should pause to notice just how astonishingly wonderful this is. But we should notice too the opportunity costs. For example, barring a zombie apocalypse, most of the people reading this post will never learn to hunt their own dinner. OK, maybe that’s not important…

  • All posts,  Self development

    How to spend less money

    There are many ways to get better at money management, though you wouldn’t know it from reading personal development blogs. They pretty much all recommend you plan out a budget and stick to it strictly, month in, month out. You set up a spreadsheet or pay for some shockingly expensive bespoke software and audit your expenditure at the end of every month. It works just fine, but it’s like counting calories. It’s tedious, and there’s a real risk you’ll one day break the diet in an alarming binge. Another approach is to change your mindset when it comes to money. Do this and frugal habits may become automatic. I think…

  • All posts,  Self development

    Using social media to live a better life

    We live in the age of the selfie, of Facebook, of Instagram, of self-generated content. This isn’t unprecedented narcisism, as some would have us believe. It’s the modern equivalent of boring your friends with four packets of photographs from you recent trip. In many ways, the modern approach is better. Tweaking an Instagram filter is fun. Re-taking a selfie until you get one without bags under your eyes might be desirable. Taking things further, learning about composition and the technology behind digital cameras, can be worthwhile. But if we’re not careful, we can end up as a sort of fifth-rate journalist. We can spend more time crafting the adjectives than…

  • All posts,  Self development

    The power of ritual

    Not too long ago, I read Mason Curry’s Daily Rituals — How Artists Work. It’s a fascinating book. Literally. I could hardly put it down. And yet, I hesitate to recommend it. The reason for my hesitation has more to do with the book’s reception than with the book itself. Oliver Burkman, writing for the Guardian describes how he was inspired by Curry’s book to change his own daily habits and rituals — rising early like Hemingway, drinking strong coffee like Beethoven, and walking outdoors like Franklin. He goes on to produce (a perhaps tongue-in-cheek) listicle based on Curry’s book, eplaining to readers, amongst other things, that practicing strategic substance abuse and…