Comments for Why are computers so dumb? at http://www.nzmac.com , comment 1 to 7 out of 7 comments http://www.nzmac.com Mon, 01 Dec 2008 17:23:46 +0100 FeedCreator 1.7.3 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-429 You can also use the time functions in Excel like =MINUTE( ) to serialise the value after you perform the calculation - MattD Wed, 06 Aug 2008 13:12:12 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-406 Don't apologise. This explanation just proves my point. It's also very interesting. Since you showed me how to calculate the time I managed to workout how to turn it into a numerical value I can use in a proper calculation. I have to admit that when it comes to maths I suck very very badly although I blame the school system for that. I had teachers who were really good at what they did but weren't so flash in explaining it. :) - lowededwookie Thu, 10 Jul 2008 16:49:45 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-404 I am conscious of getting off on a sideline here. I am not critical of your original thesis, but think there are some important things to learn about Excel Time that may lower your expectations a little. Time as we use it in real life is represented using a mixed number base: 24 hours/day, 60 minutes/hour etc. When we break down dates we get weeks, months years with complicated bases – years have 400 year cycles. One way of representing Date and Time is to use separate numbers (perhaps a byte) for each part e.g. minutes, hours etc., but it is still difficult to calculate as we must do a sum for each part and look after carries and overflows. What is done to resolve this issue in Excel is actually quite beautiful in its simplicity. Date and Time are recorded as the number of days since the year 1900 started with time recorded after the decimal point. So 12/4/08 6:00 PM is recorded as 39550.75. There are 39550 days since the 1st of Jan 1900, and 6 PM is three quarters of a day. Simple! The nice thing about this is that simple maths can be used to compute dates and times. e.g. How many days between 12/4/08 and 13/6/08? Type them like that into Excel and subtract -> 62 days Voila! It also works for times. What is the elapsed time between 12/4/08 6.30 AM and 13/6/08 6:30 PM. Again type them into Excel like that, subtract, and the answer is 62.5 days. But the caveat is: you must decide on the appropriate display format for your date/times from the many available. So the problem with wanting computer intelligence is that needs to 'know' that the 35 in 0:35 is actually an integer 35 meaning minutes. But what if you had worked for 35 hours (35:00) that is also an integer now meaning hours. This gets back to my original thesis: Your rate must be an amount divided by a time in the correct units. Now that 0.02 you got is the number 0:35 expressed as a fraction of a day i.e. 35/24/60=0.024305556 days (to 9dp). Don't expect the computer to 'know' if you are trying to compute 35 minutes at $23.08 per hour or 35 hours at $23.08 per hour - both are perfectly valid calculations and are handled well by Excel. Simply create your hourly rate by dividing $23.08 by 1:00, and then multiply the result by either 0:35 if you meant minutes and 35:00 if you meant hours. Its just a convenient convention. My apologies for this exposition on Time. I am sure Numbers allows similar things but may use slightly different formats. - BobJordanB Sun, 06 Jul 2008 23:19:53 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-403 The problem I was stating in my example is the difference between how a computer interprets an amount and how a human does it. To a computer 00:35 is seen as some weird number that I have not worked out what. When you format 00:35 to a decimal it shows as 0.02 which makes no sense. A human on the other hand will make that 00:35 a decimal value of 35 because we realise that we are looking at a time value. Humans calculate things better in decimal values so we automatically translate the time value in the equation. The semantics of the example was not the issue but how computers interpret things so differently to humans. It's this interpretation that I was trying to highlight why computers cannot get to human level intelligence along their current path. For something that's meant to be logical it goes about things completely illogically. Incidentally Numbers refuses to do your calculation but that's because Numbers doesn't do time calculations. Google Docs works the equation out correctly though as does OpenOffice and of course Excel. Man I hope Numbers adds support for time calculations. Another use for this equation is to calculate a bill to send to the council for how long I have to wait at traffic lights due to the bad timing of the lights. For each minute I spend waiting I will send them a bill based on my hourly rate. :) - lowededwookie Sat, 05 Jul 2008 23:45:05 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-402 I was not commenting on the rest of your submission,in fact i tend to agree. But it was just the numbers bit that caught my eye and sparked a recall. I think you have missed the point. There is not a problem with the 0:35, the problem is in the rate. Now a rate is a ratio of two units. $23.08 is not a rate, it is an amount. To make it into a rate you have to divide it by a time unit. So it is $23.08/hour and an hour is 1:00 in the units chosen, hence my calculation. So if I was paid $200 per 8 hours the rate is $200/8:00 which is quite close to your $23 but it uses a different amount and a different time. So you are not asking the computer to guess whether 0:35 means 35 or not, you are asking it to guess if your 'rate' is per hour, per 8 hours, per day etc. My thesis is that all numbers should have their units firmly afixed. It is hard in Excel - but possible! Cheers - BobJordanB Sat, 05 Jul 2008 14:40:18 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-401 Don't get me wrong, I thank you so much for giving me a nice simple equation but it just goes to highlight that computers are so far from how we humans think that this example proves how far computers have to go to get to where we are at birth. The above example shows how our brains work. Computers clearly have no ability to convert time into a value of worth for quick and easy computation. Why can't a spreadsheet recognise that 00:35 is actually a value of 35? If a child can actually work this out why can't a computer? In many respects computers can do equations much better than us but their output may not be what we're after. Let's go back to the example of the call system we use. The other day we got reamed because our utilisation reports were way out. Supposedly I only work 9 hours a week. Where did this information come from? From a call system that makes a report based on the updates we do in the call system. Now considering our call system falls over more often than a one legged man on a bender (this incidentally is an upgrade to the software we use and it actually falls over more often than the old version that made one legged drunkard seem stable so go figure). The report doesn't take into account numerous factors for example training, projects that aren't recorded, and jobs that we haven't updated because the system is down. A report ran at the wrong time gives the wrong picture but one a computer can't pick up on. It can't reason that I should be doing much more work than my report shows and ask me what's going on but humans can. But ultimately humans are dumber than the machines they use because they rely on a device that requires proper information. If the information they give is not telling the full story then clearly the information is of no use. Unfortunately for computers to get to human level intelligence and therefore give us the information we need and allow us to work properly we need to program computers in the way we think and that is extremely complex because we don't know how we think. How can you program something based on us when we don't understand us? - lowededwookie Sat, 05 Jul 2008 00:01:23 +0100 http://www.nzmac.com/community-blog/780-why-are-computers-so-dumb.html#comment-400 Its all a matter of putting the right things into your equation I did this in Excel using cells A1 to B9 Column A Column B Hourly Rate $23.08 Start Time14:40 End Time15:15 One hour1:00 Total $13.46 Formula '=(B4-B3)*B1/B5 So that means (End time minus start time) times dollars divided by one hour Voila! What could be easier? Bob J. - BobJordanB Fri, 04 Jul 2008 16:55:25 +0100