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# Uh? So how many is that?

## Uh? So how many is that?

(OP)
This is just totally befuddling.

#### Quote (NY Daily News):

Approximately 2,000 of the MTA's fleet of more than 10,000 buses are more than a dozen years old. NYC Transit division buses traveled on average 3,377 miles before breaking down last summer - compared to 13% fewer than the year before, according to agency statistics.

### RE: Uh? So how many is that?

MintJulep,

I can make sense of the numbers.  I just don't know what is 13% fewer than last year, the breakdowns, or the miles before breaking down.

A breakdown every 3377 miles between breakdowns sounds horrible.

JHG

### RE: Uh? So how many is that?

Sounds like DC math.

### RE: Uh? So how many is that?

Ever drive in NYC? 3400 miles could be 6 months or more with stop and go driving where they go 200-300 feet betweeen stops, if lucky.

"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli

### RE: Uh? So how many is that?

I interpret this poorly written 'math' problem to mean that;

1.  20% of MTA's fleet of 10,000 buses are well past their expected useful life.  That part is fairly easy.

2.  When bus breakdowns are averaged for the whole fleet, you get about 3,377 miles between breakdowns.  That's bad, even the old, decrepit buses.

3.  I have no idea what the 13% statement means.  Maybe the previous year the average distance between breakdowns was 13% greater?  Still no cause to celebrate.

"Gorgeous hair is the best revenge."  Ivana Trump

### RE: Uh? So how many is that?

Actually, to my mind there is information provided that is non-sequitur because the correlation was left open ended. The percentage of busses more than 12 years old might be relevant, but was not directly tied to the other facts, leaving you to IMPLY a connection.

The germane issue is apparently the frequency of breakdowns, stated (poorly) as averaging one every 3,377 bus-miles traveled. The previous year it was apparently one every 3,882 bus-miles (13% better performance).

I would have stated the germane issue first, then stated the bus age statistic and made a direct suggestion as to a link between the two. But then again, I get paid a lot more than the average Journalism major...

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)

### RE: Uh? So how many is that?

(OP)

#### Quote (jraef):

The previous year it was apparently one every 3,882 bus-miles (13% better performance).

I can't see how you get that.

My take is that the mean distance between failure was less last year.  That is, last years MDBF was 3377 - (.13 x 3377) = 2938.

### RE: Uh? So how many is that?

It's either fewer miles between beakdowns, or fewer breakdowns.

I can't confidently predict which one the journo meant as I suspect that even the 'fact' of breakdowns every 3377 miles on average has been reproduced incorrectly.

### RE: Uh? So how many is that?

Note also that it should say "compared with", not "compared to". Now that is just sloppy journalism.

- Steve

### RE: Uh? So how many is that?

I read the '13% fewer' as 13% fewer breakdowns, which would translate to a longer miles traveled before breakdown, assuming roughly the same number of miles traveled.  Yeah, the reporter was quoting some maintenance report that he or she did not fully understand.

-Kirby

Kirby Wilkerson

Remember, first define the problem, then solve it.

### RE: Uh? So how many is that?

Reporting is in the job description, understanding, no:)

Regards,

Mike

### RE: Uh? So how many is that?

I'm more drawn to the erroneous use of significant digits.  Is the number of miles between breakdowns averaged over about 2,000 buses, or more than 10,000 busses?  Either way it should be rounded to 3,000 miles between breakdowns.

Also, it may be my ignorance to the area, but I'm not aware that NYC has a transit division.  It has a department of transportation, which is apparently not synonymous with the MTA.  So, just whose busses are they?

### RE: Uh? So how many is that?

(OP)
The MTA is the Metropolitan Transportation Agency (or possibly it's Authority).  They run the NYC subway, Long Island Railroad, Metro-North Railroad, NYC Buses and some of the bridges and tunnels.

The DOT is the Department of Transportation.  They fix the roads.

That data used to generate the "statistics" is hopelessly flawed.  The statistics and underlying data are completely useless for trying to do any type of real analysis.

### RE: Uh? So how many is that?

Even the phrase 'compared to 13% fewer than the year before' doesn't make sense.

It should be 'compared to 13% fewer the year before' or '13% fewer than the year before'.

Saying 'compared to 13% fewer than the year before' does not mean that the 3377 is 13% fewer, it is saying compare it to a number that is 13% fewer than the year before, which isn't defined anywhere.

### RE: Uh? So how many is that?

Probably the folks doing these jobs are competent, but I think you are expecting FAR too much from journalists.  From what I can gather, grammar, spelling and simple arithmetic are no longer part of the job description.  Googling and twitter skills are in demand though.

### RE: Uh? So how many is that?

Business schools are filled with engineering school dropouts.  Journalism schools are filled with business school dropouts.

### RE: Uh? So how many is that?

The quotation reads as though the writer tried to translate a list of statistics into a meaningful narrative, and failed.

It's unclear whether the breakdowns have decreased by 13%, which would suggest improved maintenance, or the interval between breakdowns has decreased, indicating the busses are getting worse due to age.

It reminds me of a banner I once saw, which read:

"In the USA, a drunk driving fatality occurs every thirty minutes.  We must work to reduce this number!"

### RE: Uh? So how many is that?

LOL

"Gorgeous hair is the best revenge."  Ivana Trump

### RE: Uh? So how many is that?

So get drunk and drive more often??

And being an MTA mechanic sounds like a life long opportunity!!!

### RE: Uh? So how many is that?

95% of all Harley-Davidson's made since 2001 are still on the road.  The other 5% made it home.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

### RE: Uh? So how many is that?

Key phrase is something most people seemed miss, "according to agency statistics".  It's likely someone from the agency feed the "journalist" this intentially convoluted statement.

Matt Lorono, CSWP
Product Definition Specialist, DS SolidWorks Corp
Personal sites:
Lorono's SolidWorks Resources & SolidWorks Legion

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