A big trip

Posted on December 9th, 2015 in AutoSpeed,Driving Emotion,Opinion by Julian Edgar

So in about 3 weeks we’re off on what has become, over the last few years, an annual trip: heading to another country to see the best engineering, automotive and technically interesting sights.

This year, though, it’s more than just ‘a’ country; the plan at this stage calls for travel through seven countries.

So where are we going – and what are we going to see?

The trip starts in Oslo, Norway. We don’t expect there to be long – just a day – before we head to Sweden. In Sweden we will go to the Saab museum in Trollhättan, and Volvo museum in Gothenburg. Also in Gothenburg is the Aeroseum aviation museum – a museum housed in a Cold War era underground bunker.

From there we head across the Oresund bridge (one of the most spectacular in the world) to Denmark, and then down to the Netherlands. In the Netherlands we’re going to the Louwman Museum in The Hague. With 250 cars on display, this should be stunning. We’re also going on a dusk tour of the Rotterdam harbour, the world’s busiest port. The Erasmus bridge, a gorgeous cable-stayed design, should able to be sighted.

From Holland we enter Germany, going back to see a museum we missed last time we were in that fantastic country. It’s the Technik Museum Speyer, an extraordinary collection of aircraft, cars, locomotives, a submarine – and so on. If it’s remotely as good as its sister museum in Sinsheim, it should be a fantastic day.

We then head to Switzerland, passing through the Simplon railway tunnel, one of the oldest and most famous railway tunnels in the world. In Switzerland we’re going to the Swiss Knife Valley visitor centre, where my 11-year-old son very much hopes to make his own Victorinox pocket knife. The Swiss Museum of Transport in Lucerne is Switzerland’s best-visited museum and looks spectacular – at least in the pictures! We also hope to have time to take the train to Jungfrau – Europe’s highest mountain station at 3454 metres.

Italy is next, with the Museo Auto Italy in Turin. It has what looks to be a quite awesome collection of cars. You’d expect that we’d also go to the Ferrari and Lamborghini museums, but I’d rather see cars that caused profound social and engineering change rather than supercars that, in the grand scheme of automotive things, have achieved little.

We’re also going to Pompeii and Herculaneum. We’ve become interested in Roman ruins as a result of watching an extraordinary series that covers the engineering design of these constructions. (Do a web search under “Great courses: Understanding Greek and Roman Technology”. And note that they discount the course periodically.) From there, it’s back to more Roman ruins… in Rome.

France is next – the Millau Viaduct (that I expect to be the most impressive bridge I have ever seen) and the Pont de Gard (that should be another stunning bridge, this time a Roman-era aqueduct). While in France we’ll also be attending the Cité de l’Automobile and Cité du Train museums.

Something else I am really looking forward to are the WWII Nazi submarine pens at Lorient, huge concrete constructions designed to prevent Allied bombers destroying the German submarines then berthed there. Of the same era in terms of historic interest are the Normandy landing beaches, the location at which Allied troops started their reclaiming of occupied Europe. We also hope to go to the Eiffel tower and the Louvre in Paris. Less well known but also in Paris is the Musee Air + Espace that we plan to visit.

From France it’s to our last country – the United Kingdom. There we will visit the Birmingham Science Museum (the home of the superb Mobil Railton Special Land Speed Record car), the Air Force Museum at Cosford, and the Cardington airship sheds – the latter almost the only remaining evidence of the major engineering effort the UK made over 85 years ago in lighter-than-air craft. I’d also like to go back to the National Motor Museum at Beaulieu (we’ve been there once before but I’d love to see the Donald Campbell Bluebird Land Speed Record car again) and then to the Haynes Motor Museum at Sparkford.

We’ll be taking trains, doing one internal European flight, twice hiring cars – and no doubt walking a lot. The travel, accommodation, money – all the logistics, really – will be in the immensely capable hands of my wife Georgina. (And thank God for that!)

Have we bitten off more than we can chew? We’ll see – people have implied that about our other overseas trips, but we’ve always managed to get through everything on the itinerary.  On the other hand, there’s never been quite so much on the schedule as for this trip…

Next year I hope to bring you in AutoSpeed a ‘diary’ series on the trip, and no doubt in later articles I’ll be covering specific cars, aircraft and technical sights that I’ve seen.

Seeing Buzz Aldrin

Posted on December 7th, 2015 in Aerodynamics,AutoSpeed,Driving Emotion,Opinion,Technologies by Julian Edgar

The other day I went and saw Buzz Aldrin.

Yes, that’s right, the second person to walk on the Moon, the pilot of the Lunar Module, and a man who today is 85 years old.

I don’t think in my life I have ever gone to ‘an evening with’ type of show, let alone one hosted by Ray Martin (a local Australian TV celebrity).

I had no idea what to expect, but my wife, 11-year-old son and I all went down to the Melbourne Town Hall. There were two chairs on the stage, and a large backdrop onto which stills and video could be shown.

The show started at 8pm and finished – I reckon – at about 10.45…. so it was no 10 or 15-minute chat.

Ray asked questions – largely banal, and at times ill-researched – and Buzz occasionally answered them. Usually, though, he treated Martin with veiled, slightly amused contempt – and talked about whatever he felt like.

The first half of the show – all about the Moon landing – was just riveting. I have a technical and biographical library on space travel (perhaps 50 books) and so many of the names and events that Buzz mentioned I knew something about.

But this was from the man himself!

Whenever I started to half relax, Aldrin would come out with something that entranced me.

Earth from the Moon looks about twice as big as the Moon looks from Earth.

On the day of the launch, Aldrin paused near the top of the mighty Saturn rocket. He looked down at the tens of thousands of spectators, and thought: I need to remember this; I am going to the Moon.

I liked the man’s humour – very, very dry – and his absolute lack of the need to say something that big-noted himself.

After the break, he returned to talk about how he’d like to see people travel to Mars. A man who did his Doctor of Science in lunar rendezvous, he had plenty to say about rendezvousing on the way to that planet. Martin was completely out of his depth – he didn’t even understand stuff that was explained to him quite simply – but kind of tried to hold on. Buzz got excited – he’d obviously rather talk about the future than the past – but I am more interested in what he did, than what he thinks we can do.

The evening drew to a close, but not before some questions from the crowd. Buzz again tended to ignore the questions and just say whatever he liked, but the questions were sufficiently open that he could do that and get away with it. He leapt to his feet and prowled the stage, gesticulating and motivating.

An old, feisty, out-spoken man, brilliantly intelligent, funny, warm and… and… one of the most extraordinary explorers we have ever had.

He was just wonderful.

Thanks two million

Posted on February 2nd, 2015 in AutoSpeed by Julian Edgar

Back in February 2011 I wrote in a blog post:

Feedback from the audience can be detailed, it can be analytical and it can be highly structured. Alternatively, it can be very simple, very quick and anonymous.

At AutoSpeed we chose the latter, giving readers a 1-5 continuum they can use to assess every page of content on the site. Because it’s simple and anonymous, many people choose to provide feedback.

In fact, as this is published, we will have received close to one million page feedbacks! One million! That’s quite extraordinary – and from a writer’s perspective, it provides immense feedback value.

Well as you may have guessed, we’re just about to pass another milestone – an incredible two million feedback ratings on our articles.

That is, 2 million times, people have paused over the 1-5 ratings at the bottom of one of our articles, and thought: hmm what will I give this?

Perhaps you’ve been inspired and excited – or perhaps you’ve been pissed off and disgruntled. Or somewhere in between. Whatever your selection, it’s been noticed and factored into the mix of material we provide you.

Most AutoSpeed readers today are not those that have been following us for the last 16 years (although you, as a reader of this blog, are more likely to be one of those ‘long-termers’) but people who drop in and out. Either way, those stats go on to form averages for each article that I, as editor, look at long and hard.

Sometimes the rating is low – and I don’t agree with it. The article in question might be one that my experience suggests that over the long term, will go up and up. (Or of course I might just be completely wrong in my assessment of the article – it still happens.)

Another time, we run an article we have published previously and the new reader ratings are just extraordinarily high – much higher than when we first published it. Was the article before its time, I wonder?

And of course, other times, the ratings reflect just what I expect.

(And the average of the two million ratings? 2.87 out of 5)

Every time you read an AutoSpeed article, I encourage you to select one of the numbers down the bottom, the ones that tell me what you thought of the piece.

That way, the number will grow to 3 million….

My year

Posted on December 7th, 2014 in Aerodynamics,AutoSpeed,Driving Emotion,Economy,electric,Honda,Hybrid Power,Intercooling,Opinion by Julian Edgar

Well, it’s nearly the end of the year, and I have been reflecting on my busy car modification 12 months.

All the modifications I have done have been to my little Honda Insight.

Fitting a turbo, water/air intercooler and making and fitting a new airbox. Installing a MoTeC M400 ECU, and then doing all the engine mapping on the road. Fitting a MoTeC CDL3 dash, and then upgrading to an ADL3 dash.

It’s been a huge amount of fun turning the all-alloy, two-seater Honda hybrid into a fuel-efficient turbo with about 70 per cent more power than standard from its 1 litre, 3-cylinder engine.

None of these mods was cheap, but all gave the results I’d been hoping for.

And in the last few weeks I have been playing with the suspension. And, so far, this has been cheap! I calculated the required specs for new springs front and back, sourced them at near zero cost, then installed them. That step was very successful, so then I fitted a new rear antiroll bar – this time, for a cost of less than fifty bucks.

The car is absolutely transformed in both ride and handling – and I am yet to fit the new dampers, which at the time of writing, are on their way from the US.

Sitting in the corner is the next Insight modification – a Tritium Wavesculptor200 high voltage electric motor controller. It will be used to run the Honda’s standard 10kW electric motor, although not always at only 10kW. Given the nature of electric motors, I should be able to over-rate it for short periods, gaining perhaps 20kW for huge short-term torque.

I plan on controlling the Wavescluptor200 using outputs from the MoTeC ADL3 dash. The dash – really, a digital control system that happens to have a display – has a full range of programmable maths functions and can use 3D look-up tables.

The new high voltage battery pack and battery monitoring system? I am yet to decide on these things.

I don’t know if I will achieve my final aim of 0-100 km/h in the Sixes and fuel economy in the high Twos (litres/100km), but the challenge is enormously exciting and rewarding.

In the meantime, we’re off to the United States for five weeks. We’ll be concentrating on the eastern side of the country, and have on our itinerary a long list of technical and automotive sights – and sites. We hope to next year bring you a series in AutoSpeed that describes some of what we see.

Finally, I also published another three books this year – if you are interested, search on Amazon under my name.

Have a safe and happy Christmas and New Year, and remember: for fun and challenge, nothing beats modifying your car!

Four weeks in Germany

Posted on January 20th, 2014 in automotive history,AutoSpeed,BMW,classics,Driving Emotion,Opinion by Julian Edgar

So as I write this, I am just back from our four-week trip to Germany.

It was a trip made with the express intention of seeing as many fabulous technical, automotive and aeronautical sights as possible, and also seeing as many 1930s and 1940s historic sites as possible!

The trip was fascinating – and often rather surprising.

The revered Porsche museum is a self-indulgent wank, with history airbrushed and obfuscated to suit only Porsche and its created mystique.

The BMW museum is in the same mould: brush any commercial difficulties aside (the unsuccessful ETA engines? Never heard of them!) and just plonk cars into a space with almost zero context.

The Mercedes museum? Oh my gosh – what a stunner. Fabulous cars, lots of honesty, and lots of and lots of automotive history expressed in a cultural and technological context. The Mercedes museum is surely one of the best one-make car museums in the world – and boy, do they ever show BMW and Porsche how it should be done.

Another fantastic place to visit is the Sinsheim technic museum. It’s got cars (try some stuff like a Cord, lots of Bugattis, lots and lots of 1930s Mercedes, 1950s bubble cars, American cars of the 1960s – and on and on) and some aircraft (try a Concorde and Soviet-era Tupolev Tu-144) – and also  a whole bunch of military hardware.

Travelling as we did in winter, there’s barely a soul to be seen – so you can take your time, completely unhindered by others. It was so quiet that when looking at the outside military hardware at the Sinsheim museum, a friendly stray cat came up to visit!

Another absolute stunner is the Deutsches technical museum in Munich. I thought that the Science Museum we visited in London last year was good but the Deutsches is in another – even better – league. I defy anyone reading this to get through the content of the Deutsches technical museum in less than a full day. From the pile of Mercedes alloy V12 engine blocks in the section on metal casting, to the aeronautical display showing early aircraft wing sections as they were measured in contemporary wind tunnels, to the display on locks and keys, to the room full of machine tools of the 1800s and 1900s, to the full size stationary steam engines, the cutaway submarine (yep a real one) – it just went on and on and on.

And then when you’ve overloaded there, go to the specialised transport Deutsches museum, also in Munich….. that is also outstanding.

But we didn’t just go to museums. Going with my wife and 9-year-old son, we also visited the Lego Discovery centre in Berlin (pretty weak I thought), the Miniature Wonderland in Hamburg (the world’s largest model railway and quite fantastic), lots and lots of shops, went for  ferry ride on Lake Constance in the south – and also stayed at Zinnowitz on the Baltic Sea in the north.

Then there were the incredibly sobering Nazi-era concentration camps at Dachau and Mittelbau-Dora, the amazing architecture and feel of the Nuremberg Nazi party rally grounds – and a bunch of other stuff.

I’ll be covering a lot of it – with a huge number of pics – in a Germany Diary series we’ll be shortly running in AutoSpeed.

Old but fun

Posted on December 2nd, 2013 in AutoSpeed,Opinion,Toyota by Julian Edgar

So the other day I was in Adelaide for three days. Usually, I would hire a car, but this time a friend offered me something to drive.

The car was a 1998 Toyota Starlet, 2-door base model.

How base? No clock, no tacho, wind-up windows, manual (not power) steering. But equipped with a 4E-FE 1.3 litre DOHC EFI engine and 5 speed manual trans. I reckon the car’s worth about $1500.

Within moments of picking it up, I loved it!

What did I love about it?

Firstly, it was – to use an old term – so nippy! It was super responsive to the throttle, and I’d guess most of its city nippiness came from what seemed to be very low gearing. (No tacho, so I couldn’t tell for sure.) So, you see a hole in traffic to lane-change into – and pow!, you could be filling it.

And the car was small! You get so used to the apparently inexorable growth in dimensions of cars that you actually forget what a small car is like. The Starlet was small enough that a Toyota Echo alongside in traffic seemed huge. The Starlet wasn’t a joy to park (the manual steering being quite heavy at low speeds) but in traffic, and for that matter on winding roads, the small size made it a delight.

And the vision! I’ve written before about the stupidly small window area being used in current cars, and the Starlet was simply nothing like that – it showed how it could be done. Big rear glass, large side glass, thinner pillars….good vision everywhere.

I even got the opportunity to punch it along a tight country road – and again I thought it a lot of fun. On its tiny 165/70 tyres it did well, and the steering weight in that situation was perfect.

OK, OK – it sure as hell is a car I wouldn’t want to have crashed in. And its NVH was bloody awful – it was quite wearing to drive long distances.

Would I want to drive an old Starlet all day, every day? Not on your life!

But jumping into an old, basic car startlingly showed strengths that are being lost in current cars: throttle response, size, vision….and maybe just even just the element of fun.

 

 

AutoSpeed in 2014

Posted on October 4th, 2013 in AutoSpeed,Driving Emotion,Hybrid Power by Julian Edgar

Well, it’s an exciting automotive time for me.

I’ve been working hard on a project – turbocharging my little Honda Insight – that’s going to result in a whole bunch of interesting DIY AutoSpeed stories in 2014.

Yes, even if you’ve no particular interest in turbo’ing a hybrid!

So what sort of stories then?

Well, first off the rank, I’ve bought a TIG welder and have been learning how to drive it. I must say that it’s been a very steep learning curve: despite having experience in both MIG and gas welding, TIG’ing aluminium is a dramatic step up. I’d expect some time in 2014 to write a story about learning how to TIG weld – in the mean time, I’ve done a story for AutoSpeed on making a welding trolley to hold the unit and its gas cylinder.

One of the things I’ve been welding is a water/air intercooler heat exchanger. The Honda will use the intercooler to maintain a constant inlet air temp (eg 35 degrees C ) – not just to cool the air when on boost. This is likely to require passing engine coolant through the heat exchanger following start-up on cold days, transitioning to working as a standalone heat sink, then in hot ambient conditions to working as a conventional cooler with pump and front-radiator. The aim is to achieve best fuel economy, as well as avoid detonation caused by high intake air temps.

I’ve also made a new airbox, taking an unusual approach that is easy to build and uses a widely available, paper filter element. The result flows well, is compact and can be adapted in size and configuration as required for the particular application.

To connect the turbo to the intercooler and then the throttle body I need new intake plumbing – and I’ve been making that as well. I chose to use mild steel mandrel bends – and I’ve made a simple tool to place a bead on the ends of the tubes to stop the hoses blowing off. We’ll be covering the tool, that uses a hydraulic press to power it, in a story in 2014.

Not yet made as I write this, but on the list of things to do, is a new exhaust system. I want to incorporate something I’ve long admired – a variable flow exhaust valve. I’ve got one sitting on the shelf (taken, from all things, a Ferrari rear muffler!) and I’d like to be able to integrate it near the rear of the car.

Driving the engine will be a MoTeC M400 – initially I’ll be controlling fuel, spark, EGR, VTEC changeover and turbo boost. Sitting in the same box near my desk as I type is also a MoTeC CDL3 dash – it will be displaying as many bits of information as I can configure into it.

I’d like to later integrate electronic throttle control – but one step at a time.

And what of the ‘hybridness’ of the car? Longer term, I’d like to use a new li-ion battery pack and controller, potentially over-rating the 10kW electric motor for short term bursts. But initially at least, the car will run as just a turbo three cylinder without the hybrid system operating.

My ultimate aim is to maintain the car’s  unbelievably good fuel economy and have up to 40 per cent more power.

On a different topic, over Christmas and New Year I expect to be in Germany for a month – as we did this year for the UK, I believe that will result in some very interesting tech stories.

2014 is AutoSpeed’s 16th year of publication – it looks like there will be plenty of interesting content!

Grossly misleading technical articles

Posted on April 30th, 2009 in AutoSpeed,Opinion by Julian Edgar

Long ago, even before I was a Geography teacher, I studied how to teach it. The head of the Geography department at college was a very smart person, and a brilliant teacher.

One day we were talking about teaching analogies and models, and the difficulty in simplification of knowledge without introducing straight-out erroneous ideas.

His example of the latter was: Clouds bumping into each other make thunder.

Much better, he pointed out, to say even to the youngest child: Thunder happens because of lightning.

In fact, clouds are a good example of these ideas. My little boy, who is 4 years old, asks what clouds are made of.

Tiny, tiny water droplets, I say.

So, how does rain happen, he asks?

I say: The tiny droplets run into each other and join together. When they are big enough, they fall to the ground.

While I am saying this, sometimes I think of a much more sophisticated model: water vapour, latent heat of evaporation and condensation, relative humidity, dew-point, hygroscopic nuclei – and other concepts.

A meteorologist would probably think of vapour pressure, a chemist might think at a molecular level, a physicist might consider terminal velocities, a climatologist might consider climate change, a minister of religion might think of God, an agnostic might think of the magnificence of nature.

In the description of clouds and rainfall that I say to my son, I am conscious of the gross simplifications I am making.

But that’s OK: every single thing I know about the world is a gross simplification of reality.

The intellectual models I use to make sense of what occurs around me are just reducible approximations of what really happens.

When I write technical articles in AutoSpeed, I am conscious that all the time I am presenting fundamentally simplistic models. I hope that they’re not of the ‘clouds bumping into each other make thunder’ type: but they may be.

Recently, I wrote an article on suspension roll centres, virtual pivot points and other ways of analysing suspension designs. In doing so, I consulted five different suspension design textbooks, and also considered very carefully the experience I have in developing human-powered vehicle suspensions, and modifying car suspensions.

As always, I was quite conscious during the writing of the article that the model I was presenting of reality was likely to be flawed: as I have already implied, every model we have of reality is, to a greater or lesser degree, flawed. However, I hoped that the information would benefit people’s understandings, especially in practical outcomes.

The day after finishing the article, I looked through a complex SAE paper on suspension roll centres. This paper immediately debunked several suspension ‘myths’, most of which I had implicitly or explicitly promulgated in the article I had written.

However, the paper was working at a level analogous to the ‘vapour pressure and hygroscopic nuclei’ theory of why rain falls: if I based my article on the SAE paper in question, perhaps less than half of one percent of AutoSpeed readers would understand anything I wrote. (If in fact I could understand it myself!)

So I could easily decide not to write anything at all: if it’s not ‘right’ and ‘correct’, surely it shouldn’t be written?

But that would be like saying to my son: I cannot tell you why rain falls; it’s too hard to understand.

I cannot tell you what a roll centre is; it’s too hard to understand.

Or I cannot tell you what a voltage is; it’s too hard to understand.

I cannot tell you what engine detonation is; it’s too hard to understand.

I cannot tell you how a tyre behaves when cornering, it’s too hard to understand.

And so on.

And these things – and all things – really are too hard to understand… if you want as ‘correct’ an understanding as it is currently possible to have.

Are my articles full of errors? So by definition, very likely.

Anyone who suggests that the technical articles they present for general readers are perfectly correct – or do not mislead in the slightest – just do not understand the nature of knowledge – and how all our descriptions of what goes on around us are just relatively simplistic models.

Me? I try to use the simplest model that’s consistent with not being grossly misleading…

My driving life is now changed forever…

Posted on April 3rd, 2009 in AutoSpeed,Driving Emotion,Economy,electric,Electric vehicles,Global Warming,Opinion by Julian Edgar

I feel like one of the first pilots of jet-powered aircraft. They immediately knew that they were flying the future: there could be no going back to pistons and propellers.

Today I drove the car that, for me, spells the end of the piston engine for performance cars.

The car was the all-electric Tesla, and its performance – and the way it achieved that performance – was just so extraordinary that I am almost lost for words. That a start-up car company has created such a vehicle is simply unprecedented in the last century of automotive development.

For the Tesla is not just a sports car with incredible performance (0-100 km/h in the fours) but also a car that redefines driveability. Simply, it has the best throttle control of any car I have ever driven.

Trickle around a carpark at 1000 (electric) revs and the car drives like it has a maximum of just a few kilowatts available. It’s the pussy cat to end all pussy cats: Grandma could drive it with nary a concern in the world. Put your foot down a little and the car seamlessly accelerates: heavy urban traffic, just perfect.

But select an empty stretch of bitumen and mash your foot to the floor and expletives just stream from your mouth as the car launches forward with an unbelievable, seamless and simply immensely strong thrust.

There are no slipping clutches, no flaring torque converters, no revving engines, no gear-changes – just a swishing vacuum-cleaner-on-steroids noise that sweeps you towards the horizon. The acceleration off the line and up to 100 km/h or so is just mind-boggling – especially as it’s accompanied by such undemonstrative effort. The car will do it again and again and again, all with the same phenomenal ease that makes this the winner of any traffic lights grand prix you’re ever likely to meet.

And it’s not just off the line. Want to quickly swap lanes? Just think about it and it’s accomplished. 

In fact drive the car hard and you start assuming that this is the only mode – outright performance. But then enter that carpark, or keep station with other traffic, and you’re back to driving an utterly tractable car – in fact, one for whom the word ‘tractable’ is irrelevant. Combustion engines are tractable or intractable; this car’s electric motor controller just apportions its electron flow as required, in an endlessly seamless and subtle variation from zero to full power.

It’s not just the acceleration that is revolutionary. The braking – achieved primarily through regen – has the same brilliant throttle mapping, an approach that immediately allows even a newcomer to progressively brake to a near-standstill at exactly the chosen point.

A seamless, elastic and fluid power delivery that no conventional car can come remotely close to matching; a symphony on wheels to be played solely with the right foot; an utterly smooth and progressive performance than can be explosive or docile, urgent or somnambulant – literally, a driveline that completely redefines sports cars.

There’s no going back – my driving life is now changed forever.

Footnote: the Tesla drive was courtesy of Simon Hackett of the ISP, Internode.

The Hidden Story of Reader Ratings

Posted on March 26th, 2009 in AutoSpeed,Driving Emotion,Opinion by Julian Edgar

At the end of all AutoSpeed articles is a reader rating system – you can give any article a score from 1 (bad) to 5 (excellent). As you’d expect, AutoSpeed publisher Web Publications has internal data analysis and display of these reader ratings – now totalling literally hundreds of thousands of scores.

By importing the data into a spreadsheet, I can rank all our articles in terms of numbers of ratings, averaged ratings for individual articles, and so on. I can also see changes over time in the average reader ratings for specific articles.

The other day a reader proposed that, if an article suggests to people ideas they don’t want to hear, they are more likely to give it a low score. So in other words, instead of rating articles on the basis of the quality of journalism, expression, innovative ideas (etc) that are presented, they just rate it on the basis of whether or not they agree with it.