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ballzac

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Posts posted by ballzac

  1. Posted

    So what actually is bath salts? Is it an actual chemical or just a term used when they don't know what they are dealing with?

    Bath salts is a term like "incense" that vendors often label substances unofficially intended for consumption so that they don't need approval by the relevant authority in order to sell them. I believe mephedrone was the most common substance sold under this particular name. But when you see a video or 'news' story stating "guy on bath salts...", you can read it as "guy who may or may not be under the influence of a substance which may or may not be mephedrone...". In other words, just take it with a grain of salt as the person who titled the video/story has no more information as to what, if anything, the person was on than we viewers do.

    In fact, as far as I'm aware, none of the alleged bath salts incidents have turned out to have anything to do with mephedrone or any other 'uncommon' intoxicant. In many cases, such as the 'zombie' attacks, the person has been tested and found to have only alcohol, and sometimes cannabis, in their system. The entire reputation of 'bath salts' has arisen through rumours. There is an incident where people say the perpetrator was on bath salts, then they are found not to be, but people don't pay any attention to this uninteresting bit of truth, so next time there is a similar incident, people say it must be bath salts again. It's a self-perpetuating myth that has not one shred of evidence to back it up. The saddest part is that reporters who should know better (such as The Young Turks) continue to perpetuate this myth. One of the few sources I've seen to do fact-based stories on this is Reason Magazine. This isn't to say that mephedrone is entirely safe, but you shouldn't base your opinions of it on stories you read in the daily mail, nor on the titles of youtube videos.

    • Like 3

  2. Posted

    by even bet, I mean, the point at which the probability they have not yet met equals the probability that they have. i.e. the point at which his chance of doubling his money are equal to his chance of losing his money = even bet.

    Hmmm, I know what you're getting at, but it doesn't really make sense. If he bets on a single day, his chance of doubling his money is never equal to his chance of losing his money. On day 1 he will be 68 times more likely to lose his money than to double it, and every week after that the odds just get worse (assuming that he places his bet before week 1).

    If he wins the bet even if the couple have met prior to the day he chooses (which is essentially what your answer to this question requires as an assumption) then he is best off picking as late a date as possible to increase his chances.

    A much clearer way of stating it would have been the way you have here: On what day does "the probability they have not yet met equal the probability that they have"? But if you want to weave it into your story, then it's important for the intended meaning of the question not to be obscured :)

  3. Posted

    solution:

    1) there's a 1/14 chance of them being in the café at the same time on any given shift within any given week. There's a 1/5 chance they'll sit opposite each other...thus 1/70. 70 days average.

    2) for 0,1,2,3,4,5,6 strangers respectively, the probability that if the man and woman are also in the café that they sit opposite each other is (1/5, 5/24, 1/5, 3/10, 1/5, 0, 0) each x 1/14 = (1/70, 5/336, 1/70, 3/140, 1/70, 0, 0). Add, divide by 7, convert to a reciprocal = 1/88.421

    Thus in this situation 88.4 days average.

    3) How many days should Marcello bet for them meeting to have an equally-weighted chance in scenario 2?

    When (87.421)^n / (88.421)^n = 0.5 ie n = log0.5/log(87.421/88.421) = 60.94 days.

    4) I'll leave the rest to you....

    *weeks

     

    3) How many days should Marcello bet for them meeting to have an equally-weighted chance in scenario 2?

    When (87.421)^n / (88.421)^n = 0.5 ie n = log0.5/log(87.421/88.421) = 60.94 days.

    Not sure what you mean here. "even bet" usually just means that you double your money if you win. Seeing as returns have nothing to do with which day would be best to bet on them meeting, I ignored that. But it seems that you meant something else. Can you explain this?

  4. Posted

    I haven't posted many pictures at all in this thread, so I'd just like to say a big thank you to those of you who post regularly. I check out this thread every time a new reply is posted, and every day there is something new to entertain, amuse, bemuse, arouse, or astound me :)

    • Like 4

  5. Posted

    Heh! I never learned how to use matlab for that. Now if you're correct in saying that Q3 is the mode, then is it even possible to calculate this analytically without programming techniques?

    Well, like I said, every day in the first week occurs with the same probability, and every other day occurs with lower probability. So there are seven modes, and they are the seven days of the first week.

  6. Posted · Edited by ballzac

    clear all
    close all
    weeks_max = 1000000;
    is_other_patrons = false;
    seats = 6;
    trials = 1000000;
    met_on_day = zeros(0,trials);
    for trial = 1:trials
    for week = 1:weeks_max
    met = false;
    clear other_patrons
    if is_other_patrons
    other_patrons = randi(seats+1,1) - 1;
    else
    other_patrons = 0;
    end
    if (other_patrons
    if other_patrons > 0
    chair_patron = zeros(0,other_patrons);
    for patron = 1:other_patrons
    chair_patron(patron) = randi(seats,1);
    end
    end
    day_m = randi(7,1);
    day_f = randi(7,1);
    time_m = randi(2,1);
    time_f = randi(2,1);
    seat_taken = true;
    while seat_taken
    chair_m = randi(seats,1);
    chair_f = randi(seats,1);
    if other_patrons > 0
    for patron = 1:other_patrons
    if (chair_m ==chair_patron(patron))||(chair_f ==chair_patron(patron))
    seat_taken = true;
    break
    end
    seat_taken = false;
    end
    else
    seat_taken = false;
    end
    end
    while (chair_f == chair_m)&&(day_f == day_m)&&(time_f == time_m)
    chair_f = randi(seats,1);
    end
    table_m = ceil((chair_m-0.1)/2);
    table_f = ceil((chair_f-0.1)/2);
    if (day_f == day_m)&&(time_f == time_m)&&(table_f == table_m)
    mod = (week-1)*7+day_f;
    met = true;
    break
    end
    end
    end
    if( met == false)
    string = 'error: have not met by days_max'
    pause
    end
    met_on_day(trial) = mod;
    end
    met_on_day_ave = sum(met_on_day)/trials
    hist(met_on_day,100 )
    [met_on_day_mode, number_of_times] = mode(met_on_day)

    This is the code for in matlab. You set the is_other_patrons to true or false for questions 2 and 1, respectively. You can change seats = 6 to 5 or 8 for question 4, and set trials to whatever you want to get high accuracy, preferably 1000000 or more. weeks_max is just the maximum number of weeks that the simulation will go for if they never meet. You will get an error message if weeks_max is reached before they meet, and you would just have to increase it, but 1000000 is sufficient for the particular parameters of these questions.

    The output is the average day they meet on, the mode, and the number of times the mode occurred, and it also plots a histogram.

  7. Posted

    Oh, of course. The day to bet on is day 1. Each day has the same probability for them meeting, unless they've already met. So the probability has to continually drop. Hence why the mode is 1. Even after a million trials, there must be enough noise in my data to shift the mode to 3.

    I just realised that this is wrong, because each day in week one is equally likely because they are independent, but any day in week two is less likely than a day in week one, so if you were to bet, you would be best off picking any random day from week 1. This would explain why I didn't get 1 as the mode in my simulation.

    • Like 1

  8. Posted

    The probability I have calculated, is that if there were infinite cafes, and infinite guys and girls (i.e. infinite trials of this), then the average number of weeks it would take is 70. This number includes the couples who met on the first day implicitly, and it is not needed to explicitly include them.

    You're right. The average number of days until they meet is the probability that they will meet on day one plus the probability that they do NOT meet on day one multiplied by the average plus one:

    Avg = P(meet) + P(!meet)(1+Avg)

    =>Avg*(1-P(!meet)) = P(meet) + P(!meet)

    =>Avg*(1 - (1-P(meet)) ) = P(meet) + 1 - P(meet)

    =>Avg*P(meet) = 1

    =>Avg = 1/P(meet)

    =70

  10. Posted

    I don't think that we need to consider the days of the week separately. I can't quite say why, I'm too confused (after saying something over and over it loses its meaning :scratchhead: )

    We do need to consider the days separately. The question is not how often they will meet. It's a question of how long until they FIRST meet.

    Consider a simplified example: What is the probability that you will get the first head on the second toss of a coin?

    It's not 1/2. It is (1/2)*(1-1/2) = 1/4. There are four possibilities

    HH

    HT

    TH

    TT

    In the first two cases, your first head was on the first toss, so they don't count. The only one that counts is number three. The chance that you will get the first head on the third toss is

    (1/2)*(1-((1/2)*(1-1/2)+(1/2))) = 1/8

    It is the same for when these two first meet. On the first day it is 1/70, but on the second day it is (1/70)*(1-1/70), and on the third day it is (1/70)*(1-((1/70)*(1-1/70)+(1/70))) The difference by the third day is only 1.4%, but it's non-zero. The histograms show this clearly.

  11. Posted · Edited by ballzac

    Oh, of course. The day to bet on is day 1. Each day has the same probability for them meeting, unless they've already met. So the probability has to continually drop. Hence why the mode is 1. Even after a million trials, there must be enough noise in my data to shift the mode to 3.

     

    Well there's a 1/1 chance the woman will take a certain seat, on a certain timeslot. There's a 1/7 chance the guy will pick the same day, and a 1/2 chance it will be the same timeslot (1/14 running product). Then there's a 1/5 chance he will pick the only remaining seat which is opposite her (running product 1/70). So with this first set-up, love is expected to happen once every 70 days.

    Second and other set-ups will take more thinking ^^. Watch this space.

    In light of my comments, I think there's a problem with your analysis here. There's a 1/70 chance they will meet in week 1, but there is a (1/70)*(1-1/70) chance they will meet on day two, NOT (1/70)*(1/70), which I think your analysis relies on. This will shift the mean only slightly , and it could explain why I get 69 in my simulations, though it could also just be noise (I only ran the 1000000 trial simulation once.

    (ETA: I think in practical terms it makes FA difference, so my value of 69 would just be due to not enough trials, but it's at least of analytical interest that it would be technically less than 70)

  13. Posted

    Which says that on average, love will happen once every 43 weeks (42.9). At first this confused me. It still kind of does. I suppose that having less empty seats kinda forces them to sit together. Maybe, unless I made a mistake. :scratchhead:

    I think there are more scenarios than you gave. You gave the best case scenarios, that the seats are filled up in order. Consider that there may be only 3 patrons, each at a different table, and the probability of the couple meeting is zero. There are many more scenarios where the probability is lower than the best case scenario ... for each of the patron numbers. I think this explains why my numerical result is higher than your analytical one, though I wouldn't stake my life on mine being correct either.

    • Like 1

  14. Posted · Edited by ballzac

    Well there's a 1/1 chance the woman will take a certain seat, on a certain timeslot. There's a 1/7 chance the guy will pick the same day, and a 1/2 chance it will be the same timeslot (1/14 running product). Then there's a 1/5 chance he will pick the only remaining seat which is opposite her (running product 1/70). So with this first set-up, love is expected to happen once every 70 days.

    Second and other set-ups will take more thinking ^^. Watch this space.

    I missed this before, but glad I had another look through the thread, because this supports my numerical result for question 1, though you made the same mistake I did :)

    For question 3, if I'm understanding it correctly, we want the mode: After one million trials, the mode I found was (EDIT: well, it seems hard to believe, but I get a mode of 3 days, with a probability of 0.15%)

    For question 4, assuming that there can be 0-5 or 0-8 patrons with equal probability for each part of the question, I found that if you take a chair away, the mean number of days before they meet is 731, and if you add a table (two chairs), the mean is 869. So both appear to be worse than just leaving it as is, but out of the two, taking away a chair is better.

  17. Posted

    Shiprack

    This app has got to be one of my favourites. I order a lot of stuff online, and when there is tracking on something I am looking forward to receiving, I can become obsessive with refreshing the tracking page to see if it's "onboard with driver" that day. With shiprack, you just forward an email that has the item's tracking number in it, and it automatically adds it to your list of items with the subject line of the email as the title. If you don't have an email from the vendor, you can also add items manually. It works out what tracker to use based on the tracking number, and sends you notifications when the status of any of your items is updated. You can also click on one of your items to see the tracking history of that item.

  18. Posted

    just use bicarb soda (sodium bicarbonate) instead. Or even mylanta should work if its just for chewing with stuff like betel nut. its alot safer. When i was younger and stupid, i got some lime and chewed it with betel nut and it burned my mouth. I was peeling dead skin from inside my cheeks for a couple of days after that

    Totally agree. I actually find lime doesn't work anywhere near as well as bicarb because you will burn yourself before the pH gets high enough in your mouth. I chew tobacco quite a lot and always have a tobacco tin full of bicarb with me and it works great. Lime is nasty shit.

    • Like 1

  20. Posted

    Just a suggestion but could people please write a title and a quick blurb of what your video contains, I often skip passed a lot of them because I dont know whats in them and dont have time to check if its interesting or not.

    +1

    It also help for searchability, because (IIRC) the titles of the videos don't show up in a search unless you add it as text to the post.

    • Like 1

  21. Posted

    The big difference with mycology is that most of the incriminating posts are about wild mushrooms. Even though pictures of psilocybe mushrooms drying out on a piece of newspaper is illegal, it doesn't have the same impact on the community as potency discussion of cacti or illegal posts about other plants, because there's not a whole lot the authorities can do on a wider scale. It's more of an "at own risk" scenario. Having said that, if I was moderating the mycology forum, I would be a hard arse :devil:

    But Torsten has stated time and time again that he likes to allow each moderator plenty of freedom to use their own discretion, and this results in a range of different moderating styles across the forums.

    However, even though there are have been a lot of incriminating posts in the mycology forum (I don't know what it's like at the moment because I haven't been there in a while), you will find that if something is reported, it gets dealt with swiftly. So the simple answer is, as others have said, that if you think a post crosses the line, just report it.

  22. Posted

    I always like to find media that I think will work well with my Dad's style of art, but that he would never think to use. The flourescent pink that he ended up using in the Buddha in post #23 is one example. He's always reluctant to try them out, but always manages to put them to very good use. The latest was glitter paint that I got him. He started using it and thought it was going to end up looking kitsch, so he said he would give me the painting once it's finished, but as the painting is taking shape, he's starting to really like the effect he's getting from the glitter paint, and regrets telling me I could have it :lol:. I think it works really well. It suits the eastern aesthetic as it looks kind of bejeweled.

    The form for this was borrowed from someone else's work, just something he found online I think. But he's managed to make it all his own in his characteristic pointillist style:

    DSC00200.jpg

    DSC00199.jpg

    DSC00198.jpg

    • Like 4

  23. Posted

    As far as I know, blackmail is illegal and could get the owners in a heap of trouble. Most rental agreements say that you are not going to use the property for any illegal purposes, so if they could prove that illegal activities were occurring on their property, they could get the person kicked out. But they can't get you to comply by using the threat of exposing your activities to the police. Photos taken by the owners aren't great evidence in and of themselves, so if the person were to keep a very 'clean' house, they could probably avoid any legal problems, while possibly getting the owners in trouble if they could provide evidence that they were being blackmailed. This would depend on how much heat the tenants were willing to attract, and it would be essential to talk to a lawyer first to be sure of what would be the best course of action. I'm assuming there is a free legal aid service in their state?

    The landlord is required to provide 24 hours notice before entering your property, but is allowed to enter when you are not home. Unfortunately, the notice does not need to be sent by registered post, so the landlord can claim that notice was sent by regular post, and you won't be able to prove that this didn't occur.

    As far as the harassment goes, I don't think I can add anything helpful to what's already been said. The main thing is that this person needs to document everything that happens.

  24. Posted

    I believe even seeds available from the supermarket (in the spice aisle) can be used for this purpose, and this would save a person from risking a cultivation charge. It's still illegal, and could be considered manufacturing, but there would be less chance of getting caught (though obviously I'm not suggesting anyone break the law in any way). However, even if it was legal I would not recommend poppy tea as a safe means of ingestion, because the inability to measure out a precise dose could lead to overdose. If anyone was going to attempt this, I would suggest (in the interest of harm minimisation) to be very careful, starting with very low doses and never assuming potency of a particular brew based on a previous one.

    Just a note: growing papaver somniferum is illegal even for ornamental purposes. But, this is obviously applied at the discretion of the police and the courts, so in practice, if you're an old lady and a member of a gardening club, you will not get into trouble, but if you're a twenty-something man with tattoos down your arms and a slab of VB in the fridge, you will be doing hard time for the same crime.

    • Like 5
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