Graeme's Meandering analysis Mon, 30 Oct 2023 10:31:46 +0000 en-US hourly 1 Does web design matter? Mon, 30 Oct 2023 10:31:46 +0000 I recently visited the website of a amateur theatre company, and any web designer would say it is awful. Anyone with the slightest aesthetic sense will say it is ugly. As a user of the site, it is perfectly good and better than most sites a designer would like.

Here is the site. Just in case it disappears or changes here is a screenshot of it as it is.

As you can see it looks like a particularly bad Geocities site from the 1990s. I am sure many people will mock it. Here is why I think it is a good site.

1. The most important piece of information, the details of the next production, are right there on the home page. No hunting around.
2. Everything else I wanted to know is on a link to the about page.
3. Because the site is so simple it works perfectly on mobile without anyone having to do extra work.
4. It is accessible (for the blind_ as far as I can tell. The image correctly has an empty alt tag (as the information in it is repeated as text). Most websites get this wrong.

It has some faults. The background makes the link text hard to read. There are some broken links and “under construction” pages and out of date content. That is also true of lots of great looking sites, and is to be expected on a site maintained by a volunteer with limited time. The readability issue is easily fixed by deleting the background image (I tried blocking it and the site looked much better).

It is also far more useful to someone who wants to go to a performance than their Facebook page, the “more modern” way of doing it in many eyes. Of course, their Facebook page is likely to have other roles: to share what you are doing with friends and family, or to give people who may be interested in joining a taste of what is going on.

Of course a bigger and more commercial organisation such as the better known theatre company in town (The Royal Shakespeare Company) could not get away with having a site like this. They need to look good, keep sponsors happy and so on. In short, if the PR aspect of a nice design is important, then you need to prioritise it. If you want to put your users first, then stuff it.

Incidentally, the tiny theatre where they usually perform (the Bear Pit) has a nicer bar than the RSC too.

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No progress in two and a half millennia? Sun, 29 Oct 2023 10:09:22 +0000 This passage from (Pseudo-)Xenophon’s Constitution of the Athenians, the last sentence in particular, could have been written today, and it seems we cannot run things better now than then.

It is these poor people, this common folk, this riff-raff, whose prosperity, combined with the growth of their numbers, enhances the democracy. Whereas, a shifting of fortune to the advantage of the wealthy and the better classes implies the establishment on the part of the commonalty of a strong power in opposition to itself. In fact, all the world over, the cream of society is in opposition to the democracy.

The quote it taken from the Project Gutenberg edition.
Consider how much has changed since. Democracy was destroyed and reinvented. Of course, contemporary democracy is better in many ways than Athenian: we do not have slavery, and women can vote, and so on. In other ways our democracy is weaker and power is far more removed from the voters.

While things are undoubtedly better overall, there are also some things that never seem to change. Human nature does not.

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Racism is not one thing: experiences of different cultures Sat, 26 Aug 2023 11:02:28 +0000 I have lived in two countries, and worked in another, on different continents, and been obviously ethnic minority in all three. I will start with my own birth certificate. It states my race. It states my parents races. This was regarded as normal and necessary until just three years ago.

I have heard it defended as necessary for security (i.e. to enable racial profiling to catch terrorists) by people whose other views were sufficiently social liberal to fit in with the most woke of western institutions: it was entirely normalised.

I was born in Sri Lanka, and the racial categories used will be unfamiliar to westerners: I am Burgher (of European ancestry) because my father is – in Sri Lanka race is patrilineal. Of course, in the UK, I am British Asian. I am a demonstration that race is defined by culture, not biology.

The three biggest racial groups in Sri Lanka are Sinhala, Tamil and Muslim. As you may guess from the last (which lumps together people from multiple origins from Arabia to India to SE Asia) race is strongly linked to religion: Buddhist, Hindu, and Muslim respectively. The only one of the countries four major religions that crosses racial boundaries is Christianity.

This may have changed in the last few years, but when I last lived in Sri Lanka your race and religion were regularly recorded: for example if you made statement to the police (even if it was for a car accident). If you had a non-standard combination (if your religion was not an acceptable one for your race) it invited disbelief.

Race is strongly linked to identity: to Buddhist fundamentalist nationalists the only real Sri Lankans are Sinhala Buddhists. These are not fringe views: I can, for example, recall a government minister saying that the country belonged to the Sinhalese, and the Tamils and Muslims were “guests”.

I have lived most of my life in the UK. The big difference is that overt racism is almost entirely unacceptable. While there are undoubtedly racists, there are far, far fewer than in the 1980s: over my life I have seen a continual decline in racism.

The biggest problems are stereotypes and there are complexities to these. For example this study shows (see table 2) that the group most favoured by employers are white British women, and the next South and East Asian men. The most discriminated against groups were Pakistani and Nigerian. It is clear that the factor that matters is not skin colour, but national and religious stereotypes.

I once spent a few months working in Kenya. There the most apparent racism is the resentment by the majority of the relatively successful South Asian (all of us called “Indians”) groups. Unlike elsewhere educated professionals seem to be more racist: they feel out competed. As in some western countries, Asians are the “new Jews”: a group resented because of its success.

It is also apparent that the “Indians” live somewhat separately from the majority. Much like European Jews did.

Finally, a country that I have not lived or worked in, but that has the most influence (and a harmful one – that will be the subject of a future post) on how the world perceives and deals with racism. The USA.

It had long been obvious to me that racism in the US is far more entrenched in its culture than in the UK. This has been commented on by many people including Frederick Douglas:

They measure and esteem men according to their moral and intellectual worth, and not according to the color of their skin. Whatever may be said of the aristocracies here, there is none based on the color of a man’s skin. This species of aristocracy belongs preeminently to “the land of the free, and the home of the brave.” I have never found it abroad, in any but Americans. It sticks to them wherever they go.

There are a number of similar quotes in the chapter about the two years he spent in the UK in My Bondage and My Freedom

I had long been aware that the American perception of race is very different and rooted in the “just one drop” laws of segregation. It had long struck me that it was peculiar that Americans who wanted to be anti-racist could not get away from this. People who have no problem accepting the idea of self-assigned gender, usually regard race as an immutable characteristic. People who are obviously mixed race (President Obama) or look white to my Asian eyes (Meghan, Duchess of Sussex) are still “black”. There are other peculiarly American classifications of race such as “hispanic”.

I only really understood this when I read Isabel Wilkerson’s amazing book Caste. American racism is a caste system: the only difference between the US and India is that the entirely arbitrary markers of where you belong are different. In both you are assigned to a group on the basis of your ancestry.In both there is a hierarchy. In both your descendants cannot escape their assigned place. In both those who are mixed are assigned to the “inferior” group. Both are (or have been, in the US) by both the authorities and by systematic violence.

This makes it very different from personal prejudice, or prejudice within particular institutions. It is pervasive and it is inescapable. Even people who want to be anti-racist cannot escape it because they cannot truly free themselves of the underlying assumption that their culture’s definition of race is an eternal truth.

India has, of course, other racial and religious discrimination on top of the caste system, which makes it somewhat different from the US.

Five countries, at least five different types of racism.

Schools are failing, and flexible education is the answer Thu, 03 Aug 2023 11:40:27 +0000 Schools have been deteriorating for many years, and lockdown hastened the crisis this caused – but the deterioration dates back many years, and the underlying cause is the stubborn focus on a Victorian model of education and the addiction to metrics. The solution lies in empowering pupils and parents.

The problem is that schools are failing to achieve genuine high standards, causing severe mental health problems, and are generally struggling to cope. Many good teachers are leaving the profession because they are frustrated. Those that remain are fixed on the short term: getting high grades in this years exams.

Children are naturally born to learn. Schools often suck the joy out of learning. The need to stick to a curriculum, to make individuals with different talents and interests do exactly the same things at the same time is simply a bad idea.

The concept I have is easiest to describe in how it would apply to children of secondary school age – which,is the age group who have the most issues with school. It also works for younger children but needs more parental involvement (simply because of issues such as transport and safety – for which there are many solutions).

The solution is simple: schools cease to be “providers of everything”. A student at a school is typically there for the same hours every day, other activities such as sports are provided by schools: a single institution dominates a child’s life.

Instead schools provide classes and facilities. Other institutions provide extra resources: libraries, for example. Many resources can be provided online at a national or international level – these already exist but they could be so much more if they received government funding.

From all these parents and children choose what they want to use. They sign up for individual classes, and access the resources they want. Children good at a particular subject can move to a more advanced class, children who are struggling with a particular subject can move to an easier one. There will be more flexibility to fit in activities outside school.

It will also improve education. Teachers can teach the subject instead of focusing on league tables. Children can be sent o the classes taught in the way that best suits them. If they prefer to self study some things, then they can do so and be given access to the books, online resources, and whatever they need. They will also have a much wider range of subjects to choose from. Consider the choice of GCSEs a typical school can offer: it is nothing like the dozens that are possible (I have not done a thorough count, but it exceeds 60 subjects without even counting modern foreign languages).

Having more choices will also make learning less of a chore: it is a chore because it is compelled. I love reading, but if I have to read a book it because a chore – and this is a good example of something schools do that kills the joy. A library is a great educator.

It is also better in terms of social and personal development. Instead of spending all day in one place with the same people of exactly their own age, they will interact with far more people in multiple settings. They will be encouraged to take more responsibility for themselves instead which is a better preparation for adult life.

I know many people will be asking whether all this will work. I know it will because I have done it and it has been hugely successful. It is the commonest form of what is called “home education”. There are multiple studies around the world proving that home education works well, and that it works better than school for poorer and less well educated families.

The differences between what I propose above and what we do is that I had to pay for everything, and because it is something only a minority of people do the resources available locally are limited (which pushes us towards remote resources).  If it were adopted as national policy the budget that goes to schools, that is currently inadequate, would be enough to provide a very well resourced system on these lines (what parents pay to do this is invariably far less than the cost of school places).

Why CO₂ emissions will keep rising. Wed, 29 Mar 2023 12:17:19 +0000 We have had many climate change agreements that have not changed anything. The greenwashing was inevitable and to be expected. This graph from Our World in Data says it all: there has been no change in trajectory.

Europe and North America have reduced their emissions, but that has been more than offset by increases in other countries, and to a large extent, by moving high emission activities to those very countries. With their growing prosperity rooted in this these are exactly the countries that are unlikely to actually reduce emissions.

CO₂ emission are far more important than either offsetting or other greenhouse gas emissions. I have not always been all that concerned about climate change because (like most people) I thought of the primary effect as being temperature rises, which will have regional variations, have some benefits, have varied quite a lot (at a regional level, possibly at global) in the last few tens of thousands of years, and which both we can adapt to (and hopefully natural ecosystems too). I have recently been reading about ocean acidification, and I find that scary. It could wipe out or impoverish  whole ecosystems, globally.

A lot of the commitments have been to achieve “net zero”. This encourages greenwashing, because it leaves leaves room for doing things that make the numbers look better, but do not actually benefit the environment. You can plant some trees to offset emissions over their life, but what guarantee is there they will survive all political, economic and environmental change over decades? All the more so given many are monocultures so whole tracts could be wiped out by one disease.

Then look at some of the actual pledges. China and India have agreed to net-zero in 2060 and 2070 respectively. Nearly 40 years and nearly half a century. Will a commitment hold that long? Thinking about how much the world has changed in the last half century, I am very sceptical.

One of those changes has been that the influence of the west has dwindled, and it is in the west that there is the strongest political and popular support for limiting emissions. This will continue as Asian economies grow. In thirty years time this will all depend on Chinese and Indian politics – and China is a dictatorship that has never shown much sign of caring about the environment. India and other major growth economies have a lot to do.

Another problem, which is global, is that capitalism has a built-in bias to promoting economic activity over lack of activity, and the best thing for the environment is to do less: consume less, produce less, not do things. This encourages the sale of green products – so there is a strong incentive to do things like replacing energy infrastructure, but little incentive to preserve eco-systems by leaving them alone, so we both chop down forests, and then generate “carbon credits” by planting trees.

There are other issues with forests as well – e.g. claiming carb credits for forests no one had any intention of cutting down in the first place.  Offsetting has other problems – you can claim the offset for planting a tree when it is planted on the assumption that it will grow to maturity, but there is no guarantee that it will do so, or even that it is likely to do so. All this is encouraged by commitment to metrics that are easily cheated.

There are many other examples of things that are sold with a false promise of being “green”, or that people could do that are not done because there is no profit in it (and therefore no profit in promoting it).

I suspect some people will say that the cure for the bias in capitalism is more government control. The problem is that the biggest growth in CO₂ emissions has come from China, a country where business is controlled by the government.

Other state controlled economies do not have a great record either. The worst instance of climate change we have seen so far has been the death of the Aral Sea, which has not only turned most of what was once the world’s fourth largest inland body of water into near desert, destroying its rich ecosystem, and the economies it support, but also devastated the climate of a huge region around it. It will be extremely hard to reverse because one of the effects has been reduced rainfall feeding it. Who caused this devastation? The centrally planned Soviet Union.

Some will argue that the increase in CO₂ emissions and other pollutants by countries like China is still the fault of the rich countries, because that is where they export to, and they manufacture to export. This is true to an extent, but is far from being the whole truth. Chinese exports are about 18% of its GDP, and it exports to virtually every country: India imports more from China than the UK does.

There is also a lack of willingness to do anything about this. For example, carbon border taxes (i.e. import duties based on the emissions used to produce imported goods) have been discussed for a long time, particularly by the EU. So far, the only progress has been a (not yet implemented agreement) to require the trading of emissions trading certificates for a small number of goods from 2026. Of course, emissions trading certificates will just lead back to the same problem of greenwashing.

There are also ways around this, and it could even make the problem worse. The current proposals will only tax input products like steel and hydrogen. This will encourage the import of finished products instead. Back to step one.

There are many things people can do that will make a difference, but these are not pushed – there is no incentive to. For example urban plants, including gardens, are a significant carbon sink. It is relatively easy to make them far more effective a carbon sink and very good for wildlife. Less effort than maintaining a conventional lawn. Very few are willing to do this. In fact, the general trend in the UK has been to make things worse by replacing gardens with tarmac and decking in order to reduce maintenance.

Many people are willing to buy a new electric car (a dubious improvement given the environmental impact of manufacturing), but very few are willing to change their shopping habits or “neglect” their garden.

All the net-zero targets in the world maybe achieved, but they will not change anything. It is interesting that Greta Thurnberg has been in the news far less since she called out the greenwashing of COP27. As with many things, the metrics have now become more important than the reality. I told you so.

Homeschooling tips from a home educator Sat, 09 Jan 2021 14:05:07 +0000 My daughters were both home educated for many years (the younger one still is) and I want to share some things I have learned along the way with parents who find themselves temporarily home schooling because of lockdown.

This is all written from a British viewpoint (e.g. it assumes under 16s will be aiming to do (I)GCSEs), and also based on what worked for us: parents, children and circumstances vary.

Do not worry too much.

Neither parents, not schools, nor anyone else, will do a perfect job of education. It is intrinsically messy and uncertain. You need to figure out what will work for you and your child.

Forget the curriculum.

For children not studying exam syllabuses yet, you want learning, but what they learn is of secondary importance. They need to learn to think, and to learn study skills. English and maths are important, as they are needed to study other things. Other than that be flexible, and let children follow their interests.

Look for opportunities

Use the time to do things they do not have time to do because of school.

Hobbies can be educational: even if not directly so they develop concentration and some range of skills. My daughters did a bit of electronics when they were little (they learned to solder by 7, made little kits, improvised a few things….) and my older daughter is now doing electronics A level (and planning to do a degree in it).

It may also be an opportunity to do subjects schools do not offer. Interested in Latin or astronomy?  Want to learn programming to a useful level? Interested in philosophy? Obviously particular schools might, offer subjects, but no school can offer anything like the full range of available subjects. The sky is the limit – unless you are interested in astronomy, in which case, the observable universe is.

There are now MOOCs (large scale  online courses) that, again, many adults do for pleasure. My children have done MOOCs on everything from Dante to Haskell (a programming language no one teaches at school level – but which appeals to the mathematically inclined).

Doing interesting stuff may not advance covering the syllabus, but the motivation and knowledge pays off in the long term

Be realistic about time spent studying.

School hours are not study hours: there are breaks, assemblies, recording attendance, time between lessons and so on. There is time spent on interruptions, telling kids off, and a lot more. Studying at home should be more intense, so three hours of real study (broken up by breaks) is more than enough. Less for younger children, more for those in a final run up to GCSEs, and still more for A levels.

Keep an eye on time killing habits

TV, videos, games, social media, and more. It used to be easy to just not have a TV, but there is too much online distraction for that to work. Many routers let you block certain sites and services at certain times. Very useful.

There are lots of excellent, free, online resources

There are far too many to list here, and what is suitable depends in maturity, ability and interests. Its not hard to find them online though. Oak national Academy was set up for the pandemic – but there are also Khan Academy, Wootube, Wikibooks, BBC Bitesize, and many, many more.

Give children responsibility

The more responsibility you give children for their education, they less you need to push them. I do not know it this will work for everyone, and some kids may just drift, and it will need some conversations, guidance to make it work, and will not work all the time – but when it does its easier for parents, and children are happier

Encourage reading and creative interests.

Encourage reading, encourage any other interests they have, especially creative ones. Art or music or a good book is a respite from studying, but not a lazy one like slumping in front of the TV, but feels like relaxation.

Read around subjects instead of just text books. Looking at my own bookshelves, we have lots of things related to school subjects (maths, history, physics etc.) aimed at adults who buy them to read for pleasure.

Project Gutenberg has a huge range of free ebooks – they can be read on a phone or tablet with a suitable reader (I use FBReader).

Do NOT try do everything HE families do

You may know home educating families, or read about them and be tempted use them as a model. There may be things you can learn from what we do (that is the point of this post) but we also do a lot of things that depends on the flexibility we have because we home educate long term.

We have very different choices. For example, as often spread (I)GCSEs out over several years. We cannot do certain (I)GCSE subjects (art and PE for example) so use alternative qualifications for those – but we can do a much wider range of academic subjects: anything available to private candidates, from Sanskrit to Economics. This means we have a lot of flexibility in following a curriculum to suit the individual On the other hands schools will take a lot of decisions (which subjects and exam boards to offer) which does make life easier.

There is no such thing as Home Education Sat, 02 Jan 2021 11:57:11 +0000 The public view (shared by media and politicians) of home education often seems to be that it simultaneously means parents assiduously coaching children to get firsts in maths when they are 14 while simultaneously neglecting their education so they never get any qualifications. The problem is that they expect home education to exist in a way it simply does not.The problem is that home education is not a “thing”. The best definition is that it is every type of education that takes place outside a school and classroom setting. This covers a huge variety. There is variety in approaches, variety in subjects and qualifications, variety in everything.

At one extreme there are online schools which (in the UK, at least) are legally home education but work in almost the same way as a school does: it is just school taken online (as many things have been these days). The only real difference between that and the home schooling we have seen schools doing during lockdown is that the online schools have the advantage of being set up to work that way, and the parents involved want to do it. Personally, I see it as being school education in reality, if not in law.

At the other there is unschooling which is deliberately unstructured. Studies show it works well in practice although I am personally not comfortable with that unstructured an approach.

There is also variety in syllabus and qualifications. Most people in the UK do GCSEs, and IGCSEs (public exams typically taken at 16), but may do them early or late. However, some people do American exams, some do vocational qualifications, and so on. Some do minimal academic qualifications, some do a lot.

There is one thing that the popular view (and media and politicians) get wrong about all these approaches is the expectation that home educated children have worse opportunities for social development. This is entirely wrong: home educated children go to a variety of classes, social events, sports, and so on, meeting a wide range of people in different places: far better socialisation than meeting mostly people of their own age group in one setting.

That aside, “every kind of education outside school”, covers a lot, in addition to the two approaches I already mentioned.

Lets start with what used to be called “private education” (before American influence hijacked the term to mean “non-state schools” – British terminology is too complex to explain here for those unfamiliar with it). This is how the Queen and her siblings were educated: by tutors hired by their family. It still happens, but is obviously restricted to those who can afford it.

The obvious alternative is to send children to tutors, or classes held for home educated children. Again, these days, many classes are held online.

Another approach, just as radical as unschooling in its way, but generally more focused on academic achievement, is self-teaching. A lot of children can teach themselves if provided with textbooks and equipment. A great advantage is that they develop better study skills and self-discipline.

There are some other advantages, common to most, if not all, approaches: flexibility and tailoring education to the child. For example, a wider choice of subjects, taking some exams early (my older daughter did her first IGCSE when she was 11). There also tends to be more room for education that does not lead to qualifications: both my daughters have done online courses on subjects ranging from Dante to Haskell programming.

All these different approaches work, but how they work is very different. Differences in personal and family circumstances and differences in individual talents and personalities, also mean different HE children have very different experiences. They may mostly study by themselves, or mostly do classes, or mostly have one to one tuition. They may do entirely different combinations of subjects. Their parents may be involved in day-to-day education very heavily, or just organise things, pay bills and sign forms.

Add in the variety of exams and qualifications and you get even more variety. Imagine one child doing a variety of GCSEs in academic subjects ranging from classical Greek to computer science, taught one to one by tutors. Imagine another doing the same subjects but mostly self taught with some online courses and parental support. Imagine another doing functional skills exams (a less academic substitute for English and Maths GCSEs) and an online IT BTEC (there is such a thing). Imagine another doing Open University courses. Each may be right for the individual. Each is a very different experience, makes different demands, and has different requirements – and I have not even looked at the variety in their lives other than education.

Home education is not a way of educating, it is every way of educating bar one.

You should not home educate because of covid Sat, 12 Sep 2020 13:12:33 +0000 I am an advocate of home education, but I doubt one group of people currently switching are making the right decision. Not all, by any means: it depends on why and what you want.I am heavily involved in online HE communities and I see two groups of newcomers:

  1. Those who found their children (and often themselves) were happier learning at home during lockdown.
  2. Those who are scared of sending children back to school because of covid

These largely correspond to two other groups:

  1. Those who want to try a different way of educating their children
  2. Those who want their children physically at home, but want the school system.

The problem is with the second group. In many cases they are looking (I see them asking online) for a replacement for school, that works as much like school as possible. What they will end up is the worst of both.

I dislike the idea of “online school” because it loses the advantages of home education: the flexibility to tailor education to a child’s interests and abilities, the flexibility to take exams early or late rather than an arbitrary age, choosing from a vast range of subjects (any qualification open to private candidates), meeting lots of different people of different ages in different settings, learning study skills, self-discipline, and taking responsibility, and so on.

Some people are doing this with year 11 children only months away from taking GCSEs. They may have to change syllabus (e.g. from GCSE to IGCSE for sciences), switch to alternative qualifications (for drama or art) perhaps drop some.  I can understand why people do this, but it really should be a last resort. A good test would be whether delaying exams for an year (which would greatly reduce the problems) would be worth it.

Those with younger children have a different problem. Are they happy staying with HE long term? While you can always switch back, you need to consider practical issues such as losing school places, or going too far from the curriculum followed by schools

Covid will be gone (as a meaningful risk) in an year or two – if you think otherwise please read this explanation of virus evolution  Will you still want to HE then? What will you do then if your kids love HE and do not want to go back, but you do not want to the commitment of HE? Are you happy to stick to the school syllabus in the meantime (again negating many of the advantages of HE). Its not just that you may not have covered things in the syllabus, your kids are also likely to be ahead in their best subjects and bored in class.

What we call “home education” is what used to be called “private education” until American influence lead that to mean being educated at an independent school. It is no longer the province only of those who can hire governesses and tutors, but accessible to anyone who can afford a few textbooks, and ideally an internet connection and exam fees.

Many people have found that having children at home is good. One survey said that fathers are particular keen on it post covid. That makes sense to me, because many men are denied involvement in bringing up their children: they are at work and the children are at school. Children are happy to see more of their parents, and parents are happy to spend more time with their children.

Making it better than school takes time, effort and money (although its partially offset by things such as not taking them to school in heavy traffic, buying uniforms, etc.). It means doing things differently. Parents have to take responsibility for either teaching, or organising teaching, or ensuring children are teaching themselves. Parents have to decide on educational approaches, set/influence expectations,  help or find help when needed, and so on,  When it comes to exams you have to find exam centres, decide on syllabuses, fill in forms and pay fees. You may have to argue with an anti-HE local authority trying to bully you into sending children to school, sometimes breaking the law or lying in order to do so (it is surprising how many LAs think their policies can override legislation).

It is an amazing and rewarding experience for parents, and has worked brilliantly for my children, but you have to want to do it. If you are looking for school without a physical presence, you will instead get a second rate copy of school.

Hodder CIE IGCSE Computer Science textbook corrections Sun, 30 Aug 2020 16:24:37 +0000 My (then home educated) daughter used the Hodder Computer Science text book for CIE IGCSEs last year. It was good but we found a number of mistakes. It is still a current textbook so I am noting down some corrections.

The corrections are mostly from Lucy’s notes, but I have looked at the textbook too. Not all are important for the exam, but most could be.

Most of the problems are in Chapter 8. These are what is covered below. If I find any more relevant notes, or find any other issues, I will add them below. If you spot anything I have missed please let me know.


Hacking has meaning other than breaking into a computer system. It can also mean ingenious or cobbled together use of technology. The book’s definition is a common usage.

Cracking means maliciously breaking in into computers. The book’s definition is simply incorrect.

Viruses and malware

  • Viruses embed themselves in other software, altering the executable (program) files them selves. This may include documents that can contain software, such as office documents that allow macros.
  • A worm is a free standing executable that replicates itself.
  • A trojan is disguised as, or inserted into something else, but does not usually replicate itself. For example, a user may install an apparently useful application and find that the developer (or someone else tampering with the distributed code) has added malicious functionality.


Pharming redirects users from a website they want to use to another one. This may be done by editing the hosts file on the user’s own computer, compromising DNS servers, or compromising routers.


WEP should no longer be used. It has been replaced by WPA

Spyware and keylogging

Spyware is much broader than keylogging. Spyware might record web browser history, track media usage, and more.

Keylogging is hard to spot, and may be done with hardware (typically a recording device plugged into a USB port, with the keyboard plugged into that) as well as malicious software. Wireless keyboards may also be monitored in other ways.


  1. Are not the only mechanism for storing data in a web browser: there are also flash cookies and HTML5 storage, for example.
  2. While anonymous per se, they can be used to store personal information, or to store IDs that can be linked to personal information.


Most current web browsers no longer support SSL, or even early versions of TLS.

The term SSL is still used to refer to things associated with this layer: e.g “SSL certificates”.


MD4 is very old and rarely used. MD5, SHA-1 and other more recent algorithms are more common.

Denial of service attacks (DOS)

Attacks that flood the target usually use large numbers of machines to simultaneously attack it. These are often huge networks of PCs compromised by malware. These are called Distributed Denial of Service Attacks (DDOS).

There are may other attacks. For example, Slowloris (see proof of concept code) can bring down a web server by making more requests can many web servers can handle from a single attacking machine, but being more efficient at making requests than the servers are at handling them.

Free software

The book’s definition of free software is essentially based on one type of open source license, the GPL, but with an odd explanation of restrictions and the bizarre addition of one about “not producing software that is deemed offensive by third parties”).

Lots of information from the Free Software Foundation and the Open Source Initiative.

Open source includes free software, but not vice versa. The key difference is that free software can only be included in or modified to produce other free software. Some open source licenses allow proprietary to incorporate the code and remain closed: such software is widely used, for example in Apple’s MacOS X (and iOS) and Google Chome web browser.

Free software is subject to copyright laws – that is why the restrictions in the license are enforceable.

The important difference between open source software (including free software) and freeware is that users cannot redistribute (usually) or modify it.

The Geography of Covid Sun, 21 Jun 2020 14:47:09 +0000 I cannot explain this map, but the clear division in compelling. A few lines divide the world into high, medium and low covid death rate countries and there are few exceptions in the high and low death rate areas.

All I have done is drawn some lines to a map from Our World in Data – eight straight lines and one with a single curve.

As I said, I cannot explain it, but I can rule out some things.

Its not government policies that are critical. Our World in Data has multiple maps of government responses, and there seems to be no sign of correlation.

Its not GDP either.

My first though was of a link with GDP, but while most of the worst affected countries are rich ones, there are two many execpetions both ways.

I cannot see any obvious link to how healthy populations are either.

It occurs to me that Japan, by far the biggest (in terms of population) first world country with a low Covid death rate has an unusually healthy population: in particular a healthy diet and very low rates of obesity. Maybe some combination of wealth and health is the explanation.