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The Ski Rental Problem

lesves.github.io

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91–98 of 98 posts

Re: The Ski Rental Problem

#91

Post by david422 »

theoreticalmal wrote: post #85
david422 wrote: post #72

Earlier quoted context omitted.

> I have the same issue every year with a ride on lawn mower. Do I just pay someone weekly or buy one outright and do it myself? In this case I loathe mowing, I bought mine, ran great for 4 years, then ran into a bunch of trouble, which made me recognize the other hidden cost of ownership is simply just maintenance. A very expensive mower just sitting there, nearest potential repair shop far away, no idea how I'd eve…

I just scrapped an ICE mower for a battery powered one. No more winterizing, changing oil, or worrying about filling with gas. I still don’t like mowing, but it sucks a little less now

That's actually the situation I was in though. When your electric mower breaks you're probably on your own. I would not want to go back, but going forward definitely has it's own issues.

Re: The Ski Rental Problem

#92

Post by JohnKemeny »

porridgeraisin wrote: post #90
JohnKemeny wrote: post #29

Here's a different version of the problem. It takes 10 minutes to walk home from the bus central. The bus is late but should be here any minute now. The bus takes one minute. Do you wait or walk?

Don't you need to know the inter arrival time to solve this? I think the point is that it's a memory less distribution so you're expected to wait for the same time regardless of how long you've already waited.

Suppose you repeat this every day, and every day the bus arrives a random time between "now" and in (let's say) 30 minutes.

There is a strategy that allows you to never be worse than 2x if you knew exactly when the bus arrived: Wait for 10 minutes, and if the bus didn't arrive, walk home.

In all cases when the bus arrives between now and in 10 minutes, you do the optimal thing, and whenever the bus arrives after 10 minutes have passed, you will be home after 20 minutes, which is not worse than 2x worse than optimal.

Re: The Ski Rental Problem

#93

Post by nothercastle »

Noumenon72 wrote: post #42
lisbbb wrote: post #13

Oh man, I had no idea that the decision of whether to rent or buy skis required calculus to solve. I just figured that if you ski more than say, 3 times a season, it's probably better to own your own gear for reasons unrelated to the entry cost, but more to do with comfort, tuning, quality, and so on. Anyone who has rented skis knows that the rental fleets are trashed.

I have rented skis perhaps 70 times in my life and I have nothing bad to say about them. Maybe a broken buckle once or twice.

Nothing wrong with the rental skis but time ain’t free

Re: The Ski Rental Problem

#94

Post by nothercastle »

yojo wrote: post #77
andai wrote: post #64

Earlier quoted context omitted.

This kind of blew my mind when I realized that if you buy second hand and resell, you can own a product (often for years) for net zero dollars. I was also delighted when I realized that instead of going through the hassle and cost of moving everything across the country, I could just sell it and buy roughly the same thing in the new place... again for net zero dollars! Teleportation!

This assumes your time is free. The used market has tons of friction. I try to buy higher quality things, used if possible, and sell when I’m done with them. But this is primarily for ecological reasons. The complete cycle can be pretty annoying/time-consuming to the point that it’s probably economically a small loss. Buy-side can take a lot of trawling FB/Craigslist to find an item that hasn’t been thrashed. Plus co…

If you buy and sell online the platform and shipping fees are 15-20% of item value.

Re: The Ski Rental Problem

#95

Post by nothercastle »

_kyran wrote: post #54
Tycho wrote: post #49

Skiing is incredibly fun but I wonder if it should be put in the same category as cycling (on roads): too dangerous to be sane.

There’s a large spectrum between skiing on an uncrowded slope alone, a crowded beginner trail, hucking cliffs and backcountry in avy prone terrain. I don’t think the risk profile can be all lumped together. Much in the same way that cycling on the road has a different risk profile to on a bike path vs downhill or freeride mountain biking.

Most people get hurt because they try to learn in an uncontrolled fashion and overestimate their skill.

Re: The Ski Rental Problem

#96

Post by fastasucan »

svachalek wrote: post #55
massung wrote: post #15

This feels very similar to the “radio” or “restaurant” problem: You’re driving down the street trying to decide which restaurant to stop at (or scanning through the radio trying to decide which song to stop on). If you stop at the first, there’s a good chance something better is ahead. But if you wait too long then you risk getting stuck with something you don’t really like (the problem assumes you can’t go back). If…

Interesting. I once read somewhere that you should date at least... 6? people and leave before it gets too serious, before settling down with anyone. It seemed to imply there was math involved but it didn't explain. I think it must be the same statistics here, with some estimate of how many people you could meet and burn through without getting too old. I think people just don't really work this way but otherwise it…

I highly disagree with this, whats the point of dating others if you are perfectly happy with the one you are dating right now? Do you really lose out in life if there might be someone "better", even though you are happy?

Re: The Ski Rental Problem

#97

Post by poulsbohemian »

This is kind of an interesting problem, but it overlooks another variable, at least in the case of skis - it's not just how many days I'm going to use them this year, but also for the next few years. Yes, there are people who buy new skis regularly, but more commonly the person that makes the buy vs rent decision decides that over the next multiple seasons they intend to ski enough to justify the buy decision. This is especially true if you are buying new skis rather than say, rental skis at the end of the season (think kinda like buying a used car that has been depreciated, you can buy used skis that still have a lot of miles...). So my point is simply that the real world problem is actually even more interesting than this hypothetical.

Re: The Ski Rental Problem

#98

Post by poulsbohemian »

Loic wrote: post #10
tempay wrote: post #9

Earlier quoted context omitted.

In Switzerland it varies. Many places will also offer expert hire where you get brand-new skis and at the end of the season you can choose to buy them for cost.

FYI, the rental skis, even if they look the same as the same skis you could buy retail are not the same. They have bigger edges and a dicker base. The bindings are not the same. This is because they are built to go through the machine after each rental. Good retails skis have less "robust" but faster, thinner base, they would be dead after 3 months of rental. Source: I spend way too many hours each season in a ski sh…

>This is because they are built to go through the machine after each rental

What machine are you referring to here? It sounds like you are referring to some kind of waxing / edge sharpening / cleaning device, which would be extreme luxury compared to the rental shop at my local hill where they intake the rentals for the day and dump them back into a bucket for the next skier.

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