freakonomics of toll road

while anna was en route to u.s. i was contemplating on the thing we had been talking about. it's the toll booths. or more specifically, the ticket persons in the toll booths.

i once told anna that it seems to me that the ticket persons in the toll booths in jakarta outer ring are way slower than their counterparts in toll booths within the city limits. the farther the booths from the city, the slower the ticket persons. i had been hypothesizing that this could be due to higher flow of traffic inside the city that outside. need to test this against data.

we so far just rely on naked observation. here's the thing. the city toll road ticket price is Rp 4,000. in indonesia there's no such single paper or coin for that -- you have to give either four Rp 1,000 bills, eight Rp 500 coins (unlikely, who wants to grab eight coins while rushing?), or any of the bigger denominations: Rp 5,000; Rp 10,0000; Rp 20,000; Rp 50,000; or Rp 100,000 (the latter two unlikely -- many times the booths are not prepared to give change against these big bills).

now, what is your reason to choose the toll road and not the non-toll ones? to save time -- and you are willing to pay for saved time. so, you want to maximize time-saving. at least, i maximize time-saving. this is what i usually do when i am about to enter a city toll booth. i show (or even, waive) my money (usually i got no time to collect four Rp 1,000 bills. it's easier to grab one Rp 5,000 or one Rp 10,000) before i really reach and stop at the booth. and the ticket person who has seen my money give me my ticket and the change at the same time.

compared that to toll booth outside the inner city. i do exactly the same, but trust me, the response from the person inside the booth is ... different. no matter how obvious i showed my Rp 5,000, he or she will take it first, then ring the register, and then give me ticket and the change (fyi, the ticket costs Rp 2,500 -- but it's irrelevant to my story now; except that it is of course more difficult to manage Rp 2,500 than Rp 4,000, since the former should include one coin, for exact amount). from 2 weeks of observation, the average time i spend more on the outer jakarta toll booth is about 2 minutes, compared to the inner jakarta toll booth.

you would say: what would you make from 2 minutes? yes, that's small. but think about this: if it costs me an extra 2 minutes, what does it cost the person(s) in the vehicle right behind my car? assuming a fixed inefficiency rate of 2 minutes per ticket, that makes it 4 minutes. what does it cost the person the 15th car behind me (trust this long queue is not unusual in here)? it's 2*15 = 30 minutes! that's a real "late to the meeting"!

but i'm more intrigued by the question of why a ticket person in outer jakarta toll booth slower than that in inner jakarta toll booth? is it true that the flow of traffic higher inside jakarta than outside? maybe not. so what is it? anna offers another way out: probably only the better ticket person can be in the inner jakarta (and "better" is a reflection of a person who appreciate time in the sense of having a sense of urgency). this is interesting.

after all, i ask mysef. if i'm so picky in this thing, why don't i just prepare my exact amount of money before even driving? well that's true. but still, our friendly ticket person will take that exact Rp 2,500, then ring the register, then give the ticket with a smile...

addendum: anna just reminded over the chat: "you're exaggerating. it's less than 1 minute". maybe she's right. i was exaggerating. but even if it is less than 1 minute, the math remains. in fact, anna was telling me that if we happen to be number 10 or 15 in the line, one minute inefficiency in the booth translates to 10 to 15 minutes.