vault backup: 2026-02-20 14:53:32
This commit is contained in:
@@ -5,41 +5,8 @@ title: 2025-11-01
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tags:
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- authorship/original
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- destiny/permanent
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- original-format/typewritten-print
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- status/complete
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- type/periodic/daily
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dg-publish: true
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---
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# 2025-11-01
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# 2025-11-01 05:41:??
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_Saturday Morning_
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Somehow I've already let an hour get away from me.
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Today I need to do some cleaning: a load of laundry and leftover dishes
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at least. I'll do those after I finish this note, plus some pushups, before
|
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I shower and change to go visit the birds across the street. Later I'll need
|
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to go to the store for more sliced almonds and coconut oil so I can make granola
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for tomorrow's breakfast. I'll go to Walmart so I can get a new mattress
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protector, too. Copy paper, a 3-hole punch and a small binder would also be
|
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nice for my typewriter journaling.
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# 2025-11-01 07:06:??
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_Saturday Morning_
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I wasted more time doomscrolling after my last note, but I did manage
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to do the laundry, dishes, and pushups. Now I need to shower and dress in time
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to see the birds.
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# 2025-11-01 08:25:??
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#topic/hobbies/birding
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There were fewer than yesterday, but still a ton. There was a chill, but
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I was dressed well for it. I think with exposure the birds will get used to
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mg presence. I saw a bald eagle (_Haliaeetus leucocephalus_) for the first time
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in Florida. They are ugly creatures, of both body and spirit, unlike the wood
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stork (_Mycteria americana_) which is uglier of body, but pure of heart.
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There was also some guy getting dumped on the phone and not taking it well.
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+1
-1
@@ -71,5 +71,5 @@ enough times independently
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that I would likely benefit from it.
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I added [[leslie-et-al_1968_gregg-notehand|a book]]
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on [[shorthand#Gregg Notehand]]
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on [[shorthand#Gregg Notehand|Gregg Notehand]]
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to my calibre library.
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|
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+1
-1
@@ -1,5 +1,5 @@
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---
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id:
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id: 2025-11-20T08:46:00-05:00
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aliases: []
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tags:
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- authorship/original
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+1
-1
@@ -20,7 +20,7 @@ dg-publish: true
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#topic/meta
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I definitively think my new approach
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of putting nascent ideas in [[daily-notes|daily notes]]
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of putting nascent ideas in [[periodic-notes|daily notes]]
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rather than separate fleeting notes
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is superior.
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@@ -9,6 +9,8 @@ tags:
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- type/periodic/daily
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dg-publish: true
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---
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# 2026-01-02
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# 2026-01-02 10:10:18
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### Harborside Plaza 4
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-113
@@ -10,116 +10,3 @@ tags:
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dg-publish: true
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---
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# 2026-01-12
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# 2026-01-12 10:00:??
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#occupational
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### ECH3 Executed Contract Revision WBS
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For Executed Contract Revisions, Bid GP% must be maintained.
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In this case a negative variance was added to the buyout budget
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in order to compensate for an increase in permit fee coverage.
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# 2026-01-12 10:42:30
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#occupational
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### Woodbrook Executed Contract Revision Takeoff Check
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#### Unit Dishwasher/Disposal
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Drawings show 2 separate duplex receptacles for dishwasher and disposal
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Takeoff used `DW & DISPOSAL DUAL CIR - ...`,
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which includes only one receptacle.
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According to Joel this takeoff is correct for the scenario.
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# 2026-01-12 12:23:??
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#occupational
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Travelling with Brian Smarslok and Joel Jansen on [[2026-01-15]]
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to visit [[#Woodbury Heights|an awarded project]] in New Jersey.
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Flying from TPA to PHL, departure @ 7:00AM.
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We'll be meeting with the developer, [Greystar](https://www.greystar.com/).
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### Woodbury Heights
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```yaml
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project-name: GSC Ltd. Woodbury Heights (aka Academy Pointe)
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sector: Residential
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market-type: Apartment
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bldg-type: Garden
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construction-method: Wood Frame
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construction-type: V
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unit-wiring-method: Romex
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code-data: NEC2020
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mech-system: Split Dx
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buildings: 9
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floors: 3
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units: 234
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gross-area: 266,272
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area-by-type:
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- exterior-amenity: 12,306
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- interior-amenity: 5,031
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- garage: 3,788
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- saleable: 223,172
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division: MA 1
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geographic-region: Northeast
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metro-area: New York-Newark-Jersey City, NY-NJ-PA
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municipality-or-ahj: City of Woodbury
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power-company: PSE&G
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stakeholders:
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- developer: Greystar (HQ - Charleston, SC)
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architect: LS3P Associates Ltd
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electrical-engineer: Hurst Engineering
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contract-value: 2,305,000.00
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start-date: 2025-05-01
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end-date: 2026-08-26
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duration: 11 months
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```
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|
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#### GP Variance
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> [!info]
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> "GP%" is **margin** (see [[markup-vs-margin]]).
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The job appears to be doing poorly, at current GP variance of -$299,356.
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About $93,000.00 profit on a $2,391,378 job (~3% margin, down from 16.4% as bid).
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Intend to ask Joel what was missed if he knows,
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and more generally if he has a strategy for figuring out,
|
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between BPM, The Hub, and however many other places we can look.
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I doubt very seriously that mismanagement
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can be blamed for any significant portion of variance that extreme.
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# 2026-01-12 13:02:??
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#topic/construction
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**Dry utilities:** utilities other than "wet" utilities (water, sewer, stormwater),
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namely power, data, and natural gas.
|
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# 2026-01-12 13:02:??
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#occupational
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Joel attributes the [[#GP Variance|apparent variance]] to
|
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1. missed Polaris lugs for feeders for one building,
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2. insufficient budget for equipment rental, and
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3. upfront costs already paid (construction is 50% complete).
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|
||||
He also said that operations accused ConEst
|
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of providing insufficient length for subfeeds,
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which he said was true,
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but not to the extent accused
|
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(only ~600ft missed total).
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|
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The award WBS shows $32,382 for equipment rental
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|
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I'm dubious of all these explanations,
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but I don't have another one.
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I can't find the ConEst folder or Accubid file.
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|
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@@ -10,60 +10,3 @@ tags:
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dg-publish: true
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---
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# 2026-01-19
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# 2026-01-19 11:57:39
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||||
Follow-up to [[2026-01-10#2026-01-10 08:42]]
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A **natural language parser** would be a big help
|
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for the sort of formatting I've been doing recently.
|
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|
||||
[[nfpa-70_national-electric-code]]
|
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|
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[[semantic-line-breaks]]
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|
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[[2025-10-26#2025-10-26 18:36 --- Sunday evening]]
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|
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# 2026-01-19 12:32:??
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#topic/construction #topic/estimating
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Real example of [[location-vs-scope]]:
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450-460 James Robertson Parkway Phase II (fka James Roberston Pkwy Mixed Use Development)
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Project is two buildings: Residential and Hotel,
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entirely separate physically and electrically.
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Generators for both are located on a lower roof of Residential.
|
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|
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# 2026-01-19 18:13:??
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### Smart Home
|
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One of the most exciting aspects of home ownership to me
|
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is that I'll finally be able to go full smart home.
|
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|
||||
A programmable thermostat is at the top of my todo list,
|
||||
for energy efficiency, but mostly habit enforcement.
|
||||
I can not sleep without blankets, and I can not sleep hot.
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Turning on the lights as an alarm is usually effective,
|
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but when it's cold I find it hard not cover my face and go back to sleep.
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|
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In general the ability to make one's house unfit for relaxation
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at certain hours of the week is very powerful.
|
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|
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Google's Nest is the stereotypical smart thermostat,
|
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but devices using a local, non-Wi-Fi protocol
|
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like [Zigbee](https://en.wikipedia.org/wiki/Zigbee)
|
||||
or [Z-Wave](https://en.wikipedia.org/wiki/Z-Wave)
|
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ought to be preferred.
|
||||
|
||||
### Ulysses Pacts
|
||||
|
||||
The most challenging part of implementing Ulysses pacts with yourself
|
||||
is that sometimes you really _do_ need to jump in after the sirens, %% that's a stretch %%
|
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but if you allow yourself an out for emergencies
|
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you will almost certainly use it inappropriately in a moment of weakness.
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I know I will, anyway.
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Rarely can my fear of disappointing myself
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overwhelm the immediate appeal of whatever I'm keeping from myself.
|
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|
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@@ -10,29 +10,3 @@ tags:
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dg-publish: true
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---
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# 2026-01-20
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# 2026-01-20 09:09:12
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Stumbled upon this line while waiting on my computer to restart.
|
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|
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> [!quote] [[hubbard_2020_failure#The Measurement Inversion]]
|
||||
> Unless we estimate the value of information,
|
||||
> we may go down the deep rabbit hole of adding more and more detail to a model
|
||||
> and trying to gather data on less relevant issues.
|
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|
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# 2026-01-20 10:10:??
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I was reminded again of [[2025-12-04#2025-12-04 09:51]].
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I added a [[small-tasks|task]] for it.
|
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|
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[html-calculators](https://github.com/ZaneMeyers/html-calculators)
|
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|
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I'm now certain that common estimating calculators
|
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(e.g. voltage drop)
|
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could be easily replaced with documents like this one.
|
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|
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# 2026-01-20 14:25:??
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||||
|
||||
Jfarrari The Unknowing (Acoustic)
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|
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[[music-analysis]]
|
||||
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@@ -10,79 +10,3 @@ tags:
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dg-publish: true
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---
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# 2026-01-22
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# 2026-01-22 09:55:42
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|
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#occupational
|
||||
|
||||
The lighting drawings for
|
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450-460 James Robertson Parkway Phase II
|
||||
(fka James Roberston Pkwy Mixed Use Development)
|
||||
show occupancy sensors serving electrical rooms.
|
||||
I knew this was understood to be prohibited,
|
||||
but could not have provided a code reference.
|
||||
|
||||
[[nfpa-70_110_requirements#110.26(D) Illumination.|110.26(D)]]
|
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is the relevant section.
|
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|
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# 2026-01-22 11:58:??
|
||||
|
||||
#occupational
|
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|
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### 463 Davison Contract Dates
|
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|
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[[463-davison-ave-ne]]
|
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|
||||
Effective date: [[2026-01-21]]
|
||||
|
||||
* [x] Escrow deposit due by [[2026-01-26]]
|
||||
* [x] Loan application submitted by [[2026-01-26]]
|
||||
* [x] Inspection period ends [[2026-01-28]]
|
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* [x] Loan approval due by [[2026-02-11]]
|
||||
* [ ] Title commitment due by [[2026-02-27]]
|
||||
|
||||
Closing: [[2026-03-04]]
|
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|
||||
# 2026-01-22 14:56:??
|
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|
||||
#topic/estimating
|
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|
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### Accurate Budget Vs. Accurate BOM
|
||||
|
||||
#### Quote
|
||||
|
||||
> [!quote] Joel Jansen [[2026-01-15#2026-01-15 13:27]] (pp.)
|
||||
> I'd rather have an accurate budget than an accurate BOM.
|
||||
|
||||
#### Context
|
||||
|
||||
#### Analysis
|
||||
|
||||
It may be counterintuitive to BOM-oriented estimators
|
||||
(typical of those with an electrical background),
|
||||
but deviating from organization standard practice
|
||||
to make an assembly "more accurate"
|
||||
(read: to make the estimate BOM
|
||||
more closely resemble the construction BOM),
|
||||
may make the budget _less_ accurate.
|
||||
|
||||
The review and adjustment process
|
||||
is based on standard practice,
|
||||
so deviations may have unpredictable effects.
|
||||
|
||||
Our assemblies do not include screws.
|
||||
It would be more accurate to the BOM to add them,
|
||||
but we budget for that cost in the summary,
|
||||
so to do so would be double dipping.
|
||||
|
||||
Though not stated as such,
|
||||
we budget for takeoff-to-install deviations the same way.
|
||||
|
||||
\
|
||||
|
||||
An organization's takeoff database
|
||||
ought to include exactly what is necessary for takeoff
|
||||
at the acceptable level of detail, and nothing else.
|
||||
It ought to be assumed by estimators that the previous is true,
|
||||
and that acceptable takeoff of any scope
|
||||
must be possible with the contents of the database.
|
||||
|
||||
@@ -11,33 +11,4 @@ dg-publish: true
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||||
---
|
||||
# 2026-01-23
|
||||
|
||||
# 2026-01-23 08:18:53
|
||||
|
||||
This morning I was thinking about the "slippery slope fallacy"
|
||||
and how it's a common instrument of an appeal to fallacy fallacy.
|
||||
As it turns out, the potential validity of slippery slope arguments is well studied.
|
||||
|
||||
[Sorites paradox](https://en.wikipedia.org/wiki/Sorites_paradox#Continuum_fallacy)
|
||||
|
||||
[Many-valued logic](https://en.wikipedia.org/wiki/Many-valued_logic)
|
||||
|
||||
[Fuzzy logic](https://en.wikipedia.org/wiki/Fuzzy_logic)
|
||||
|
||||
Strictly speaking, a slippery slope argument is only fallacious
|
||||
if it is not _necessarily_ true that one event must follow another.
|
||||
|
||||
# 2026-01-23 12:34:??
|
||||
|
||||
Migrated several notes from Google's Keep
|
||||
|
||||
[[2025-10-20#2025-10-20 ??:??]]
|
||||
|
||||
[[2026-01-04#2026-01-04 ??:??]]
|
||||
|
||||
[[my-resoluute-banjo]]
|
||||
|
||||
[[pats-browning-a5]]
|
||||
|
||||
# 2026-01-23 12:56:??
|
||||
|
||||
Today the vault hit 50,000 words not including reference material.
|
||||
|
||||
-114
@@ -10,117 +10,3 @@ tags:
|
||||
dg-publish: true
|
||||
---
|
||||
# 2026-01-25
|
||||
|
||||
# 2026-01-25 18:46:??
|
||||
|
||||
#topic/finance
|
||||
|
||||
### Calculating Monthly Principal & Interest Payment
|
||||
|
||||
For a **fixed-rate, fully-amortizing mortgage**,
|
||||
the monthly payment is computed using the **standard amortization formula**:
|
||||
|
||||
#### Standard Amortization Formula
|
||||
|
||||
$$
|
||||
A = P \cdot \frac{i(1+i)^n}{(1+i)^n-1}
|
||||
$$
|
||||
|
||||
Where:
|
||||
|
||||
* $A$ = periodic payment amount
|
||||
* $P$ = amount of principal, net of initial payments
|
||||
* $i$ = periodic interest rate
|
||||
* $n$ = total number of payments
|
||||
|
||||
> [!info]
|
||||
> $A$ is constant over the term,
|
||||
> the interest portion decreases while the principal portion increases.
|
||||
|
||||
#### Example
|
||||
|
||||
For a 30-year mortgage of $268,000 at 5.75% annual interest:
|
||||
|
||||
$$
|
||||
\begin{align*}
|
||||
P &= 268000
|
||||
i &= \frac{0.0575}{12} = 0.004791\bar{6} \\
|
||||
n &= 30 \cdot 12 = 360
|
||||
\end{align*}
|
||||
$$
|
||||
|
||||
The monthly payment amount $A$ is given by:
|
||||
|
||||
$$
|
||||
\begin{align*}
|
||||
A &= 268000 \cdot \frac{0.004791\bar{6} \cdot (1+ 0.004791\bar{6})^{360}}{(1+ 0.004791\bar{6})^{360} - 1} \\
|
||||
A &\approx 1563.98
|
||||
\end{align*}
|
||||
$$
|
||||
|
||||
### Calculating Annual Percentage Rate (APR)
|
||||
|
||||
$$
|
||||
\text{APR} = \frac{\frac{\text{Interest} + \text{Fees}}{\text{Principle}}}{\text{Term Years}}
|
||||
$$
|
||||
|
||||
# 2026-01-25 21:02:??
|
||||
|
||||
[[the-failure-of-risk-management]]
|
||||
|
||||
If I have a general complaint about [[hubbard_2020_failure]] it's this:
|
||||
Hubbard fails to recognize logical parallels between his different arguments,
|
||||
so to a critical reader they appear contradictory:
|
||||
|
||||
In [[hubbard_2020_failure#Break It Down, Then Do the Math]]
|
||||
Hubbard introduces **decomposition** as a method for reducing error in estimates,
|
||||
Providing Fermi's "piano tuners in Chicago" problem as an example,
|
||||
without acknowledging that _Fermi_ supplied the decomposition.
|
||||
Hubbard also references [[macgregor_1994_judgemental-decomposition]]
|
||||
which is a similar case.
|
||||
Neither of these examples suggest that decomposition is a magic bullet,
|
||||
or even that a layman's decomposition wouldn't be worse than nothing.
|
||||
Despite this, Hubbard ends the section without qualifier:
|
||||
"Clearly, decomposition helps estimates."
|
||||
|
||||
This section comes only pages after
|
||||
[[hubbard_2020_failure#The Measurement Inversion]]
|
||||
in which Hubbard warns against seeking detail for the sake of it.
|
||||
|
||||
See also [[the-failure-of-risk-management#_Exsupero Ursus_]].
|
||||
|
||||
# 2026-01-25 22:59:??
|
||||
|
||||
[[macgregor_1994_judgemental-decomposition]]
|
||||
|
||||
I really hate this study.
|
||||
|
||||
I may be out of my league,
|
||||
but it seems wrong to draw conclusions about decomposition as a method
|
||||
when the work was done by the researchers,
|
||||
especially when some of their decompositions really suck.
|
||||
|
||||
> ##### Circumference of 50¢ coin
|
||||
>
|
||||
> * Diameter in inches of a 50¢ coin
|
||||
> * Number of pieces of string the length of the diameter needed to wrap around circumference
|
||||
|
||||
That's not a decomposition.
|
||||
If you don't remember $\pi$
|
||||
that's a harder problem than it was before.
|
||||
|
||||
> ##### Bushels of wheat
|
||||
>
|
||||
> * Population of the world
|
||||
> * Number of bushels of wheat consumed per person per year
|
||||
> * Proportion of wheat wasted per year
|
||||
|
||||
I might have included how much a bushel is,[^1]
|
||||
there's an order of magnitude right there.
|
||||
|
||||
[^1]: $1~\text{US bushel} \equiv 9\frac{3571}{11550}~\text{US Gallons} \approx 9.3~\text{US Gallons}$
|
||||
|
||||
The study suggests decomposition has no effect on estimate _confidence_
|
||||
---which I'm tempted to believe because its funny
|
||||
and it tracks with my anecdotal experience---
|
||||
but I wonder if subjects using their own decompositions would present similarly.
|
||||
|
||||
@@ -10,38 +10,3 @@ tags:
|
||||
dg-publish: true
|
||||
---
|
||||
# 2026-01-28
|
||||
|
||||
# 2026-01-28 09:51:08
|
||||
|
||||
#occupational
|
||||
|
||||
### ConEst OneNote Template
|
||||
|
||||
The ConEst OneNote template concept
|
||||
is flawed in ways that can not be addressed in OneNote,
|
||||
but it has good ideas, too;
|
||||
some I would not have thought could work so well.
|
||||
|
||||
#### Takeoff Checklist
|
||||
|
||||
At Ace my takeoff notes were entirely freeform,
|
||||
and I would have balked at the idea of using a standard checklist.
|
||||
Our projects were so varied
|
||||
that no list could be generic enough
|
||||
to approach universal applicability
|
||||
without being so shallow
|
||||
as to be useless to an experienced estimator.
|
||||
|
||||
#### Estimator Initials
|
||||
|
||||
Voluntary commitment to responsibility.
|
||||
An estimator adding their initials
|
||||
knows they are expected to be familiar with the scope.
|
||||
|
||||
# 2026-01-28 10:02:??
|
||||
|
||||
#topic/meta
|
||||
|
||||
I'm tempted to replace [[daily-notes]] with timestamped notes
|
||||
from core plugins Unique Note Creator,
|
||||
however the utility of the calendar widget is hard to concede.
|
||||
|
||||
@@ -10,98 +10,3 @@ tags:
|
||||
dg-publish: true
|
||||
---
|
||||
# 2026-01-29
|
||||
|
||||
# 2026-01-29 10:07:37
|
||||
|
||||
#topic/estimating
|
||||
|
||||
A peer's senior, expressing frustration,
|
||||
told them that it if they disagree with an instruction,
|
||||
they must have a reason,
|
||||
implying that the estimator's previous complaints,
|
||||
which were based on conflicting direction
|
||||
received from other estimators and seniors,
|
||||
were made _without_ reason.
|
||||
|
||||
See [[realism-vs-instrumentalism]].
|
||||
|
||||
The peer's senior is looking for a _realist_ objection to his methods,
|
||||
which an estimator without field experience (which the senior has)
|
||||
would be unlikely to be able to provide.
|
||||
Their dismissal of legitimate _instrumental_ complaints
|
||||
(misplaced effort, and deviation from more widely accepted standards)
|
||||
speaks to a fundamental misunderstanding of the purpose of estimating.
|
||||
|
||||
# 2026-01-29 17:57:??
|
||||
|
||||
#topic/finance
|
||||
|
||||
### Calculating Utility of Above-Minimum Mortgage Payment
|
||||
|
||||
See [[2026-01-25#Calculating Monthly Principal & Interest Payment]].
|
||||
|
||||
Homeowners are often advised to make elective mortgage payments
|
||||
to reduce the total interest paid on the loan,
|
||||
but an unrelated investment with a sufficient return
|
||||
could outweigh the reduced loss.
|
||||
|
||||
Suppose you have a budget surplus of $E$ dollars
|
||||
and are deciding whether to make an elective payment on your mortgage
|
||||
or to invest in a promising opportunity.
|
||||
|
||||
The return on electing to pay $E$ to the mortgage
|
||||
is the
|
||||
(i.e., interest that will no longer accrue)
|
||||
at the end of the loan is:
|
||||
|
||||
$$
|
||||
R_{\text{mortgage}} = E(1+i)^{n}
|
||||
$$
|
||||
|
||||
> [!info]- Explanation
|
||||
> This formula may seem suspiciously straightforward,
|
||||
> but suppose you did _not_ contribute $E$.
|
||||
> That portion of the principle would accrue interest
|
||||
> every month at rate $i$.
|
||||
> After $n$ months, the interest accrued by that portion is given by:
|
||||
>
|
||||
> $$
|
||||
> E(1+i)^{n}
|
||||
> $$
|
||||
|
||||
If the same $E$ is invested elsewhere at monthly return $j$,
|
||||
its future value after $n$ months takes the same form:
|
||||
|
||||
$$
|
||||
\text{FV}_{\text{investment}} = E(1+j)^{n}
|
||||
$$
|
||||
|
||||
Therefore, $j$ must exceed $i$
|
||||
for the alternative investment to be preferable to elective payment.
|
||||
|
||||
Note that $i$ and $j$ are adjusted rates,
|
||||
including respect for taxes and utility.
|
||||
|
||||
On second thought, in a utility context,
|
||||
time preference could make $j$ preferable
|
||||
even when slightly lower.
|
||||
|
||||
Short-term investments may be favored
|
||||
when liquidity is needed during the term,
|
||||
and tax deferred investments (IRA)
|
||||
are strongly favored over elective payment
|
||||
since interest is deductible
|
||||
(effective interest < nominal).
|
||||
|
||||
### Calculating Effect of Elective Payment on Term Length
|
||||
|
||||
The monthly payment and interest rate are fixed,
|
||||
so the term length must decrease
|
||||
|
||||
$$
|
||||
\begin{align}
|
||||
A &= P \cdot \frac{i(1+i)^n}{(1+i)^n-1} \\
|
||||
P &= A \cdot \frac{(1+i)^n-1}{i(1+i)^n} \\
|
||||
n &= \frac{\ln\left(\frac{A}{A-Pi}\right)}{\ln(1+i)} \\
|
||||
\end{align}
|
||||
$$
|
||||
|
||||
@@ -10,90 +10,3 @@ tags:
|
||||
dg-publish: true
|
||||
---
|
||||
# 2026-01-30
|
||||
|
||||
# 2026-01-30 08:44:29
|
||||
|
||||
#topic/meta
|
||||
|
||||
Follow-up to [[2026-01-28#2026-01-28 10:02]].
|
||||
|
||||
I really would like to implement timestamped notes,
|
||||
especially while it's still somewhat practical to split my old dailies.
|
||||
|
||||
Only the lack of plugin support stops me.
|
||||
|
||||
# 2026-01-30 09:06:??
|
||||
|
||||
#topic/meta
|
||||
|
||||
I tried the Smart Connections community plugin.
|
||||
I can't imagine who it could be useful for.
|
||||
It seems to just identify large blocks of similar content,
|
||||
which means that every daily note is connected to every other.
|
||||
|
||||
# 2026-01-30 13:42:??
|
||||
|
||||
Often when I consider learning a new skill or improving an existing one,
|
||||
I conceive of a system that would _force_ me to improve,
|
||||
rather than forget about it (as I am won to do).
|
||||
See [[2026-01-19#Ulysses Pacts]].
|
||||
|
||||
Conventional "home assistant" tech and doctrine
|
||||
caters to a class of people I find bizarre,
|
||||
those that would spend enormous sums of cash and effort
|
||||
just for the marginal benefit
|
||||
of not having to touch light switches as often as normal people.
|
||||
Instead they get to take out their phone,
|
||||
find and open the light switch app,
|
||||
and touch a virtual light switch
|
||||
because the routines they programmed were too conservative.
|
||||
|
||||
Human or software,
|
||||
an assistant without agency
|
||||
_and the will to contradict you_
|
||||
is worthless.
|
||||
If the effort to _communicate_ your instructions
|
||||
exceeds the effort to perform them,
|
||||
you will always do the task yourself.
|
||||
|
||||
# 2026-01-30 16:29:??
|
||||
|
||||
#topic/math/statistics
|
||||
|
||||
### Laplace's Rule of Succession (LRS)
|
||||
|
||||
> [!info]
|
||||
> Pierre-Simon Laplace
|
||||
|
||||
If some event occurred $m$ times in $n$ observations,
|
||||
the probability the event will occur in the next observation
|
||||
is given by:
|
||||
|
||||
$$
|
||||
\frac{1+m}{2+n}
|
||||
$$
|
||||
|
||||
### Rule of Five
|
||||
|
||||
The probability that any given sample is above the median is 50%.
|
||||
The probability that the minimum and maximum values of $n$ samples
|
||||
_don't_ straddle the median is $(\frac{1}{2})^{n}$,
|
||||
equivalent to getting the same result on a flipped coin
|
||||
$n$ times in a row.
|
||||
|
||||
There is a 93.75% chance that the median of a population
|
||||
is between the smallest and largest values
|
||||
in any random sample of five from that population.
|
||||
|
||||
# 2026-01-30 18:33:??
|
||||
|
||||
#topic/personal-productivity
|
||||
|
||||
Why is it that I find it so easy, even compulsory,
|
||||
to clean my house while working from home,
|
||||
even after returning from work on-site?
|
||||
Why again does that feeling of necessity
|
||||
persist even into the evening,
|
||||
when I would normally be home anyway,
|
||||
but unable to summon the will to do anything
|
||||
about rapidly growing piles of dirty dishes and clothes?
|
||||
|
||||
+1
-1
@@ -20,7 +20,7 @@ For those that do, see [[TODO]].
|
||||
_Task_ (italicized) as used in this note,
|
||||
refers specifically to the Task community plugin's definition.
|
||||
|
||||
_Tasks_ should generally be created only in [[daily-notes]].
|
||||
_Tasks_ should generally be created only in [[periodic-notes]].
|
||||
If created in the note they reference they will want to be deleted after resolution,
|
||||
which I feel defeats the purpose of the plugin.
|
||||
|
||||
|
||||
@@ -153,7 +153,7 @@ in the wider industry.
|
||||
### #type/idea
|
||||
|
||||
> [!danger] Deprecated Tag
|
||||
> Use of this tag has been deprecated in favor of [[daily-notes]].
|
||||
> Use of this tag has been deprecated in favor of [[periodic-notes]].
|
||||
|
||||
Items of `#type/idea` are recommendation
|
||||
that I do something in the future,
|
||||
|
||||
+1
-1
@@ -30,7 +30,7 @@ The rest is whatever else I feel is worth writing down.
|
||||
It's hard for me to reconcile the idea of daily notes
|
||||
with the purpose of [[personal-knowledge-management]] as I see it.
|
||||
Nonetheless, they are popular, and generally enjoyable to write.
|
||||
See [[daily-notes]] for appropriate use.
|
||||
See [[periodic-notes]] for appropriate use.
|
||||
|
||||
## Purpose
|
||||
|
||||
|
||||
@@ -16,8 +16,6 @@ dg-publish: true
|
||||
|
||||
## Estimating Isn't Engineering
|
||||
|
||||
#topic/estimating
|
||||
|
||||
A peer recently expressed frustration to me
|
||||
about the declining quality of construction drawings,
|
||||
specifically how systems are often missing details
|
||||
|
||||
@@ -0,0 +1,24 @@
|
||||
---
|
||||
id:
|
||||
aliases: []
|
||||
title: 2025-11-01 05:41:??
|
||||
tags:
|
||||
- authorship/original
|
||||
- destiny/permanent
|
||||
- original-format/typewritten-print
|
||||
- status/draft
|
||||
- type/timestamped
|
||||
dg-publish: true
|
||||
---
|
||||
# 2025-11-01 05:41:??
|
||||
|
||||
_Saturday Morning_
|
||||
|
||||
Somehow I've already let an hour get away from me.
|
||||
Today I need to do some cleaning: a load of laundry and leftover dishes
|
||||
at least. I'll do those after I finish this note, plus some pushups, before
|
||||
I shower and change to go visit the birds across the street. Later I'll need
|
||||
to go to the store for more sliced almonds and coconut oil so I can make granola
|
||||
for tomorrow's breakfast. I'll go to Walmart so I can get a new mattress
|
||||
protector, too. Copy paper, a 3-hole punch and a small binder would also be
|
||||
nice for my typewriter journaling.
|
||||
@@ -0,0 +1,19 @@
|
||||
---
|
||||
id:
|
||||
aliases: []
|
||||
title: 2025-11-01 07:06:??
|
||||
tags:
|
||||
- authorship/original
|
||||
- destiny/permanent
|
||||
- original-format/typewritten-print
|
||||
- status/draft
|
||||
- type/timestamped
|
||||
dg-publish: true
|
||||
---
|
||||
# 2025-11-01 07:06:??
|
||||
|
||||
_Saturday Morning_
|
||||
|
||||
I wasted more time doomscrolling after my last note, but I did manage
|
||||
to do the laundry, dishes, and pushups. Now I need to shower and dress in time
|
||||
to see the birds.
|
||||
@@ -0,0 +1,21 @@
|
||||
---
|
||||
id:
|
||||
aliases: []
|
||||
title: 2025-11-01 08:25:??
|
||||
tags:
|
||||
- authorship/original
|
||||
- destiny/permanent
|
||||
- original-format/typewritten-print
|
||||
- status/draft
|
||||
- topic/hobbies/birding
|
||||
- type/timestamped
|
||||
dg-publish: true
|
||||
---
|
||||
# 2025-11-01 08:25:??
|
||||
|
||||
There were fewer than yesterday, but still a ton. There was a chill, but
|
||||
I was dressed well for it. I think with exposure the birds will get used to
|
||||
mg presence. I saw a bald eagle (_Haliaeetus leucocephalus_) for the first time
|
||||
in Florida. They are ugly creatures, of both body and spirit, unlike the wood
|
||||
stork (_Mycteria americana_) which is uglier of body, but pure of heart.
|
||||
There was also some guy getting dumped on the phone and not taking it well.
|
||||
@@ -6,12 +6,12 @@ tags:
|
||||
- authorship/original
|
||||
- destiny/permanent
|
||||
- status/complete
|
||||
- occupational
|
||||
- type/minutes
|
||||
dg-publish: true
|
||||
---
|
||||
# 2025-11-04 14:52:05
|
||||
|
||||
#occupational #type/minutes
|
||||
|
||||
### Belle Meade Director Review
|
||||
|
||||
#### Takeoff Review
|
||||
|
||||
@@ -7,14 +7,13 @@ tags:
|
||||
- destiny/permanent
|
||||
- status/draft
|
||||
- type/timestamped
|
||||
- occupational
|
||||
dg-publish: true
|
||||
---
|
||||
# 2025-11-18 16:33:??
|
||||
|
||||
## Elliot St. ConEst Senior Review
|
||||
|
||||
#occupational
|
||||
|
||||
%%
|
||||
Transcription of notes
|
||||
taken while reviewing Elliot St. with Joel Jansen.
|
||||
|
||||
@@ -0,0 +1,9 @@
|
||||
# 2026-01-12 10:00:??
|
||||
|
||||
#occupational
|
||||
|
||||
### ECH3 Executed Contract Revision WBS
|
||||
|
||||
For Executed Contract Revisions, Bid GP% must be maintained.
|
||||
In this case a negative variance was added to the buyout budget
|
||||
in order to compensate for an increase in permit fee coverage.
|
||||
@@ -0,0 +1,13 @@
|
||||
# 2026-01-12 10:42:30
|
||||
|
||||
#occupational
|
||||
|
||||
### Woodbrook Executed Contract Revision Takeoff Check
|
||||
|
||||
#### Unit Dishwasher/Disposal
|
||||
|
||||
Drawings show 2 separate duplex receptacles for dishwasher and disposal
|
||||
Takeoff used `DW & DISPOSAL DUAL CIR - ...`,
|
||||
which includes only one receptacle.
|
||||
|
||||
According to Joel this takeoff is correct for the scenario.
|
||||
@@ -0,0 +1,60 @@
|
||||
# 2026-01-12 12:23:??
|
||||
|
||||
#occupational
|
||||
|
||||
Travelling with Brian Smarslok and Joel Jansen on [[2026-01-15]]
|
||||
to visit [[#Woodbury Heights|an awarded project]] in New Jersey.
|
||||
Flying from TPA to PHL, departure @ 7:00AM.
|
||||
We'll be meeting with the developer, [Greystar](https://www.greystar.com/).
|
||||
|
||||
### Woodbury Heights
|
||||
|
||||
```yaml
|
||||
project-name: GSC Ltd. Woodbury Heights (aka Academy Pointe)
|
||||
sector: Residential
|
||||
market-type: Apartment
|
||||
bldg-type: Garden
|
||||
construction-method: Wood Frame
|
||||
construction-type: V
|
||||
unit-wiring-method: Romex
|
||||
code-data: NEC2020
|
||||
mech-system: Split Dx
|
||||
buildings: 9
|
||||
floors: 3
|
||||
units: 234
|
||||
gross-area: 266,272
|
||||
area-by-type:
|
||||
- exterior-amenity: 12,306
|
||||
- interior-amenity: 5,031
|
||||
- garage: 3,788
|
||||
- saleable: 223,172
|
||||
division: MA 1
|
||||
geographic-region: Northeast
|
||||
metro-area: New York-Newark-Jersey City, NY-NJ-PA
|
||||
municipality-or-ahj: City of Woodbury
|
||||
power-company: PSE&G
|
||||
stakeholders:
|
||||
- developer: Greystar (HQ - Charleston, SC)
|
||||
architect: LS3P Associates Ltd
|
||||
electrical-engineer: Hurst Engineering
|
||||
contract-value: 2,305,000.00
|
||||
start-date: 2025-05-01
|
||||
end-date: 2026-08-26
|
||||
duration: 11 months
|
||||
```
|
||||
|
||||
#### GP Variance
|
||||
|
||||
> [!info]
|
||||
> "GP%" is **margin** (see [[markup-vs-margin]]).
|
||||
|
||||
The job appears to be doing poorly, at current GP variance of -$299,356.
|
||||
|
||||
About $93,000.00 profit on a $2,391,378 job (~3% margin, down from 16.4% as bid).
|
||||
|
||||
Intend to ask Joel what was missed if he knows,
|
||||
and more generally if he has a strategy for figuring out,
|
||||
between BPM, The Hub, and however many other places we can look.
|
||||
|
||||
I doubt very seriously that mismanagement
|
||||
can be blamed for any significant portion of variance that extreme.
|
||||
@@ -0,0 +1,27 @@
|
||||
# 2026-01-12 13:02:??
|
||||
|
||||
#topic/construction
|
||||
|
||||
**Dry utilities:** utilities other than "wet" utilities (water, sewer, stormwater),
|
||||
namely power, data, and natural gas.
|
||||
|
||||
# 2026-01-12 13:02:??
|
||||
|
||||
#occupational
|
||||
|
||||
Joel attributes the [[#GP Variance|apparent variance]] to
|
||||
1. missed Polaris lugs for feeders for one building,
|
||||
2. insufficient budget for equipment rental, and
|
||||
3. upfront costs already paid (construction is 50% complete).
|
||||
|
||||
He also said that operations accused ConEst
|
||||
of providing insufficient length for subfeeds,
|
||||
which he said was true,
|
||||
but not to the extent accused
|
||||
(only ~600ft missed total).
|
||||
|
||||
The award WBS shows $32,382 for equipment rental
|
||||
|
||||
I'm dubious of all these explanations,
|
||||
but I don't have another one.
|
||||
I can't find the ConEst folder or Accubid file.
|
||||
@@ -0,0 +1,12 @@
|
||||
# 2026-01-19 11:57:39
|
||||
|
||||
Follow-up to [[2026-01-10#2026-01-10 08:42]]
|
||||
|
||||
A **natural language parser** would be a big help
|
||||
for the sort of formatting I've been doing recently.
|
||||
|
||||
[[nfpa-70_national-electric-code]]
|
||||
|
||||
[[semantic-line-breaks]]
|
||||
|
||||
[[2025-10-26#2025-10-26 18:36 --- Sunday evening]]
|
||||
@@ -0,0 +1,11 @@
|
||||
# 2026-01-19 12:32:??
|
||||
|
||||
#topic/construction #topic/estimating
|
||||
|
||||
Real example of [[location-vs-scope]]:
|
||||
|
||||
450-460 James Robertson Parkway Phase II (fka James Roberston Pkwy Mixed Use Development)
|
||||
|
||||
Project is two buildings: Residential and Hotel,
|
||||
entirely separate physically and electrically.
|
||||
Generators for both are located on a lower roof of Residential.
|
||||
@@ -0,0 +1,31 @@
|
||||
# 2026-01-19 18:13:??
|
||||
|
||||
### Smart Home
|
||||
|
||||
One of the most exciting aspects of home ownership to me
|
||||
is that I'll finally be able to go full smart home.
|
||||
|
||||
A programmable thermostat is at the top of my todo list,
|
||||
for energy efficiency, but mostly habit enforcement.
|
||||
I can not sleep without blankets, and I can not sleep hot.
|
||||
Turning on the lights as an alarm is usually effective,
|
||||
but when it's cold I find it hard not cover my face and go back to sleep.
|
||||
|
||||
In general the ability to make one's house unfit for relaxation
|
||||
at certain hours of the week is very powerful.
|
||||
|
||||
Google's Nest is the stereotypical smart thermostat,
|
||||
but devices using a local, non-Wi-Fi protocol
|
||||
like [Zigbee](https://en.wikipedia.org/wiki/Zigbee)
|
||||
or [Z-Wave](https://en.wikipedia.org/wiki/Z-Wave)
|
||||
ought to be preferred.
|
||||
|
||||
### Ulysses Pacts
|
||||
|
||||
The most challenging part of implementing Ulysses pacts with yourself
|
||||
is that sometimes you really _do_ need to jump in after the sirens, %% that's a stretch %%
|
||||
but if you allow yourself an out for emergencies
|
||||
you will almost certainly use it inappropriately in a moment of weakness.
|
||||
I know I will, anyway.
|
||||
Rarely can my fear of disappointing myself
|
||||
overwhelm the immediate appeal of whatever I'm keeping from myself.
|
||||
@@ -0,0 +1,8 @@
|
||||
# 2026-01-20 09:09:12
|
||||
|
||||
Stumbled upon this line while waiting on my computer to restart.
|
||||
|
||||
> [!quote] [[hubbard_2020_failure#The Measurement Inversion]]
|
||||
> Unless we estimate the value of information,
|
||||
> we may go down the deep rabbit hole of adding more and more detail to a model
|
||||
> and trying to gather data on less relevant issues.
|
||||
@@ -0,0 +1,10 @@
|
||||
# 2026-01-20 10:10:??
|
||||
|
||||
I was reminded again of [[2025-12-04#2025-12-04 09:51]].
|
||||
I added a [[small-tasks|task]] for it.
|
||||
|
||||
[html-calculators](https://github.com/ZaneMeyers/html-calculators)
|
||||
|
||||
I'm now certain that common estimating calculators
|
||||
(e.g. voltage drop)
|
||||
could be easily replaced with documents like this one.
|
||||
@@ -0,0 +1,5 @@
|
||||
# 2026-01-20 14:25:??
|
||||
|
||||
Jfarrari The Unknowing (Acoustic)
|
||||
|
||||
[[music-analysis]]
|
||||
@@ -0,0 +1,13 @@
|
||||
# 2026-01-22 09:55:42
|
||||
|
||||
#occupational
|
||||
|
||||
The lighting drawings for
|
||||
450-460 James Robertson Parkway Phase II
|
||||
(fka James Roberston Pkwy Mixed Use Development)
|
||||
show occupancy sensors serving electrical rooms.
|
||||
I knew this was understood to be prohibited,
|
||||
but could not have provided a code reference.
|
||||
|
||||
[[nfpa-70_110_requirements#110.26(D) Illumination.|110.26(D)]]
|
||||
is the relevant section.
|
||||
@@ -0,0 +1,17 @@
|
||||
# 2026-01-22 11:58:??
|
||||
|
||||
#occupational
|
||||
|
||||
### 463 Davison Contract Dates
|
||||
|
||||
[[463-davison-ave-ne]]
|
||||
|
||||
Effective date: [[2026-01-21]]
|
||||
|
||||
* [x] Escrow deposit due by [[2026-01-26]]
|
||||
* [x] Loan application submitted by [[2026-01-26]]
|
||||
* [x] Inspection period ends [[2026-01-28]]
|
||||
* [x] Loan approval due by [[2026-02-11]]
|
||||
* [ ] Title commitment due by [[2026-02-27]]
|
||||
|
||||
Closing: [[2026-03-04]]
|
||||
@@ -0,0 +1,43 @@
|
||||
# 2026-01-22 14:56:??
|
||||
|
||||
#topic/estimating
|
||||
|
||||
### Accurate Budget Vs. Accurate BOM
|
||||
|
||||
#### Quote
|
||||
|
||||
> [!quote] Joel Jansen [[2026-01-15#2026-01-15 13:27]] (pp.)
|
||||
> I'd rather have an accurate budget than an accurate BOM.
|
||||
|
||||
#### Context
|
||||
|
||||
#### Analysis
|
||||
|
||||
It may be counterintuitive to BOM-oriented estimators
|
||||
(typical of those with an electrical background),
|
||||
but deviating from organization standard practice
|
||||
to make an assembly "more accurate"
|
||||
(read: to make the estimate BOM
|
||||
more closely resemble the construction BOM),
|
||||
may make the budget _less_ accurate.
|
||||
|
||||
The review and adjustment process
|
||||
is based on standard practice,
|
||||
so deviations may have unpredictable effects.
|
||||
|
||||
Our assemblies do not include screws.
|
||||
It would be more accurate to the BOM to add them,
|
||||
but we budget for that cost in the summary,
|
||||
so to do so would be double dipping.
|
||||
|
||||
Though not stated as such,
|
||||
we budget for takeoff-to-install deviations the same way.
|
||||
|
||||
\
|
||||
|
||||
An organization's takeoff database
|
||||
ought to include exactly what is necessary for takeoff
|
||||
at the acceptable level of detail, and nothing else.
|
||||
It ought to be assumed by estimators that the previous is true,
|
||||
and that acceptable takeoff of any scope
|
||||
must be possible with the contents of the database.
|
||||
@@ -0,0 +1,14 @@
|
||||
# 2026-01-23 08:18:53
|
||||
|
||||
This morning I was thinking about the "slippery slope fallacy"
|
||||
and how it's a common instrument of an appeal to fallacy fallacy.
|
||||
As it turns out, the potential validity of slippery slope arguments is well studied.
|
||||
|
||||
[Sorites paradox](https://en.wikipedia.org/wiki/Sorites_paradox#Continuum_fallacy)
|
||||
|
||||
[Many-valued logic](https://en.wikipedia.org/wiki/Many-valued_logic)
|
||||
|
||||
[Fuzzy logic](https://en.wikipedia.org/wiki/Fuzzy_logic)
|
||||
|
||||
Strictly speaking, a slippery slope argument is only fallacious
|
||||
if it is not _necessarily_ true that one event must follow another.
|
||||
@@ -0,0 +1,11 @@
|
||||
# 2026-01-23 12:34:??
|
||||
|
||||
Migrated several notes from Google's Keep
|
||||
|
||||
[[2025-10-20#2025-10-20 ??:??]]
|
||||
|
||||
[[2026-01-04#2026-01-04 ??:??]]
|
||||
|
||||
[[my-resoluute-banjo]]
|
||||
|
||||
[[pats-browning-a5]]
|
||||
@@ -0,0 +1,52 @@
|
||||
# 2026-01-25 18:46:??
|
||||
|
||||
#topic/finance
|
||||
|
||||
### Calculating Monthly Principal & Interest Payment
|
||||
|
||||
For a **fixed-rate, fully-amortizing mortgage**,
|
||||
the monthly payment is computed using the **standard amortization formula**:
|
||||
|
||||
#### Standard Amortization Formula
|
||||
|
||||
$$
|
||||
A = P \cdot \frac{i(1+i)^n}{(1+i)^n-1}
|
||||
$$
|
||||
|
||||
Where:
|
||||
|
||||
* $A$ = periodic payment amount
|
||||
* $P$ = amount of principal, net of initial payments
|
||||
* $i$ = periodic interest rate
|
||||
* $n$ = total number of payments
|
||||
|
||||
> [!info]
|
||||
> $A$ is constant over the term,
|
||||
> the interest portion decreases while the principal portion increases.
|
||||
|
||||
#### Example
|
||||
|
||||
For a 30-year mortgage of $268,000 at 5.75% annual interest:
|
||||
|
||||
$$
|
||||
\begin{align*}
|
||||
P &= 268000
|
||||
i &= \frac{0.0575}{12} = 0.004791\bar{6} \\
|
||||
n &= 30 \cdot 12 = 360
|
||||
\end{align*}
|
||||
$$
|
||||
|
||||
The monthly payment amount $A$ is given by:
|
||||
|
||||
$$
|
||||
\begin{align*}
|
||||
A &= 268000 \cdot \frac{0.004791\bar{6} \cdot (1+ 0.004791\bar{6})^{360}}{(1+ 0.004791\bar{6})^{360} - 1} \\
|
||||
A &\approx 1563.98
|
||||
\end{align*}
|
||||
$$
|
||||
|
||||
### Calculating Annual Percentage Rate (APR)
|
||||
|
||||
$$
|
||||
\text{APR} = \frac{\frac{\text{Interest} + \text{Fees}}{\text{Principle}}}{\text{Term Years}}
|
||||
$$
|
||||
@@ -0,0 +1,24 @@
|
||||
# 2026-01-25 21:02:??
|
||||
|
||||
[[the-failure-of-risk-management]]
|
||||
|
||||
If I have a general complaint about [[hubbard_2020_failure]] it's this:
|
||||
Hubbard fails to recognize logical parallels between his different arguments,
|
||||
so to a critical reader they appear contradictory:
|
||||
|
||||
In [[hubbard_2020_failure#Break It Down, Then Do the Math]]
|
||||
Hubbard introduces **decomposition** as a method for reducing error in estimates,
|
||||
Providing Fermi's "piano tuners in Chicago" problem as an example,
|
||||
without acknowledging that _Fermi_ supplied the decomposition.
|
||||
Hubbard also references [[macgregor_1994_judgemental-decomposition]]
|
||||
which is a similar case.
|
||||
Neither of these examples suggest that decomposition is a magic bullet,
|
||||
or even that a layman's decomposition wouldn't be worse than nothing.
|
||||
Despite this, Hubbard ends the section without qualifier:
|
||||
"Clearly, decomposition helps estimates."
|
||||
|
||||
This section comes only pages after
|
||||
[[hubbard_2020_failure#The Measurement Inversion]]
|
||||
in which Hubbard warns against seeking detail for the sake of it.
|
||||
|
||||
See also [[the-failure-of-risk-management#_Exsupero Ursus_]].
|
||||
@@ -0,0 +1,35 @@
|
||||
# 2026-01-25 22:59:??
|
||||
|
||||
[[macgregor_1994_judgemental-decomposition]]
|
||||
|
||||
I really hate this study.
|
||||
|
||||
I may be out of my league,
|
||||
but it seems wrong to draw conclusions about decomposition as a method
|
||||
when the work was done by the researchers,
|
||||
especially when some of their decompositions really suck.
|
||||
|
||||
> ##### Circumference of 50¢ coin
|
||||
>
|
||||
> * Diameter in inches of a 50¢ coin
|
||||
> * Number of pieces of string the length of the diameter needed to wrap around circumference
|
||||
|
||||
That's not a decomposition.
|
||||
If you don't remember $\pi$
|
||||
that's a harder problem than it was before.
|
||||
|
||||
> ##### Bushels of wheat
|
||||
>
|
||||
> * Population of the world
|
||||
> * Number of bushels of wheat consumed per person per year
|
||||
> * Proportion of wheat wasted per year
|
||||
|
||||
I might have included how much a bushel is,[^1]
|
||||
there's an order of magnitude right there.
|
||||
|
||||
[^1]: $1~\text{US bushel} \equiv 9\frac{3571}{11550}~\text{US Gallons} \approx 9.3~\text{US Gallons}$
|
||||
|
||||
The study suggests decomposition has no effect on estimate _confidence_
|
||||
---which I'm tempted to believe because its funny
|
||||
and it tracks with my anecdotal experience---
|
||||
but I wonder if subjects using their own decompositions would present similarly.
|
||||
@@ -0,0 +1,26 @@
|
||||
# 2026-01-28 09:51:08
|
||||
|
||||
#occupational
|
||||
|
||||
### ConEst OneNote Template
|
||||
|
||||
The ConEst OneNote template concept
|
||||
is flawed in ways that can not be addressed in OneNote,
|
||||
but it has good ideas, too;
|
||||
some I would not have thought could work so well.
|
||||
|
||||
#### Takeoff Checklist
|
||||
|
||||
At Ace my takeoff notes were entirely freeform,
|
||||
and I would have balked at the idea of using a standard checklist.
|
||||
Our projects were so varied
|
||||
that no list could be generic enough
|
||||
to approach universal applicability
|
||||
without being so shallow
|
||||
as to be useless to an experienced estimator.
|
||||
|
||||
#### Estimator Initials
|
||||
|
||||
Voluntary commitment to responsibility.
|
||||
An estimator adding their initials
|
||||
knows they are expected to be familiar with the scope.
|
||||
@@ -0,0 +1,7 @@
|
||||
# 2026-01-28 10:02:??
|
||||
|
||||
#topic/meta
|
||||
|
||||
I'm tempted to replace \[\[daily-notes\]\] with timestamped notes
|
||||
from core plugins Unique Note Creator,
|
||||
however the utility of the calendar widget is hard to concede.
|
||||
@@ -0,0 +1,20 @@
|
||||
# 2026-01-29 10:07:37
|
||||
|
||||
#topic/estimating
|
||||
|
||||
A peer's senior, expressing frustration,
|
||||
told them that it if they disagree with an instruction,
|
||||
they must have a reason,
|
||||
implying that the estimator's previous complaints,
|
||||
which were based on conflicting direction
|
||||
received from other estimators and seniors,
|
||||
were made _without_ reason.
|
||||
|
||||
See [[realism-vs-instrumentalism]].
|
||||
|
||||
The peer's senior is looking for a _realist_ objection to his methods,
|
||||
which an estimator without field experience (which the senior has)
|
||||
would be unlikely to be able to provide.
|
||||
Their dismissal of legitimate _instrumental_ complaints
|
||||
(misplaced effort, and deviation from more widely accepted standards)
|
||||
speaks to a fundamental misunderstanding of the purpose of estimating.
|
||||
@@ -0,0 +1,73 @@
|
||||
# 2026-01-29 17:57:??
|
||||
|
||||
#topic/finance
|
||||
|
||||
### Calculating Utility of Above-Minimum Mortgage Payment
|
||||
|
||||
See [[2026-01-25#Calculating Monthly Principal & Interest Payment]].
|
||||
|
||||
Homeowners are often advised to make elective mortgage payments
|
||||
to reduce the total interest paid on the loan,
|
||||
but an unrelated investment with a sufficient return
|
||||
could outweigh the reduced loss.
|
||||
|
||||
Suppose you have a budget surplus of $E$ dollars
|
||||
and are deciding whether to make an elective payment on your mortgage
|
||||
or to invest in a promising opportunity.
|
||||
|
||||
The return on electing to pay $E$ to the mortgage
|
||||
is the
|
||||
(i.e., interest that will no longer accrue)
|
||||
at the end of the loan is:
|
||||
|
||||
$$
|
||||
R_{\text{mortgage}} = E(1+i)^{n}
|
||||
$$
|
||||
|
||||
> [!info]- Explanation
|
||||
> This formula may seem suspiciously straightforward,
|
||||
> but suppose you did _not_ contribute $E$.
|
||||
> That portion of the principle would accrue interest
|
||||
> every month at rate $i$.
|
||||
> After $n$ months, the interest accrued by that portion is given by:
|
||||
>
|
||||
> $$
|
||||
> E(1+i)^{n}
|
||||
> $$
|
||||
|
||||
If the same $E$ is invested elsewhere at monthly return $j$,
|
||||
its future value after $n$ months takes the same form:
|
||||
|
||||
$$
|
||||
\text{FV}_{\text{investment}} = E(1+j)^{n}
|
||||
$$
|
||||
|
||||
Therefore, $j$ must exceed $i$
|
||||
for the alternative investment to be preferable to elective payment.
|
||||
|
||||
Note that $i$ and $j$ are adjusted rates,
|
||||
including respect for taxes and utility.
|
||||
|
||||
On second thought, in a utility context,
|
||||
time preference could make $j$ preferable
|
||||
even when slightly lower.
|
||||
|
||||
Short-term investments may be favored
|
||||
when liquidity is needed during the term,
|
||||
and tax deferred investments (IRA)
|
||||
are strongly favored over elective payment
|
||||
since interest is deductible
|
||||
(effective interest < nominal).
|
||||
|
||||
### Calculating Effect of Elective Payment on Term Length
|
||||
|
||||
The monthly payment and interest rate are fixed,
|
||||
so the term length must decrease
|
||||
|
||||
$$
|
||||
\begin{align}
|
||||
A &= P \cdot \frac{i(1+i)^n}{(1+i)^n-1} \\
|
||||
P &= A \cdot \frac{(1+i)^n-1}{i(1+i)^n} \\
|
||||
n &= \frac{\ln\left(\frac{A}{A-Pi}\right)}{\ln(1+i)} \\
|
||||
\end{align}
|
||||
$$
|
||||
@@ -0,0 +1,10 @@
|
||||
# 2026-01-30 08:44:29
|
||||
|
||||
#topic/meta
|
||||
|
||||
Follow-up to [[2026-01-28_10-02-00]].
|
||||
|
||||
I really would like to implement timestamped notes,
|
||||
especially while it's still somewhat practical to split my old dailies.
|
||||
|
||||
Only the lack of plugin support stops me.
|
||||
@@ -0,0 +1,8 @@
|
||||
# 2026-01-30 09:06:??
|
||||
|
||||
#topic/meta
|
||||
|
||||
I tried the Smart Connections community plugin.
|
||||
I can't imagine who it could be useful for.
|
||||
It seems to just identify large blocks of similar content,
|
||||
which means that every daily note is connected to every other.
|
||||
@@ -0,0 +1,24 @@
|
||||
# 2026-01-30 13:42:??
|
||||
|
||||
Often when I consider learning a new skill or improving an existing one,
|
||||
I conceive of a system that would _force_ me to improve,
|
||||
rather than forget about it (as I am won to do).
|
||||
See [[2026-01-19#Ulysses Pacts]].
|
||||
|
||||
Conventional "home assistant" tech and doctrine
|
||||
caters to a class of people I find bizarre,
|
||||
those that would spend enormous sums of cash and effort
|
||||
just for the marginal benefit
|
||||
of not having to touch light switches as often as normal people.
|
||||
Instead they get to take out their phone,
|
||||
find and open the light switch app,
|
||||
and touch a virtual light switch
|
||||
because the routines they programmed were too conservative.
|
||||
|
||||
Human or software,
|
||||
an assistant without agency
|
||||
_and the will to contradict you_
|
||||
is worthless.
|
||||
If the effort to _communicate_ your instructions
|
||||
exceeds the effort to perform them,
|
||||
you will always do the task yourself.
|
||||
@@ -0,0 +1,28 @@
|
||||
# 2026-01-30 16:29:??
|
||||
|
||||
#topic/math/statistics
|
||||
|
||||
### Laplace's Rule of Succession (LRS)
|
||||
|
||||
> [!info]
|
||||
> Pierre-Simon Laplace
|
||||
|
||||
If some event occurred $m$ times in $n$ observations,
|
||||
the probability the event will occur in the next observation
|
||||
is given by:
|
||||
|
||||
$$
|
||||
\frac{1+m}{2+n}
|
||||
$$
|
||||
|
||||
### Rule of Five
|
||||
|
||||
The probability that any given sample is above the median is 50%.
|
||||
The probability that the minimum and maximum values of $n$ samples
|
||||
_don't_ straddle the median is $(\frac{1}{2})^{n}$,
|
||||
equivalent to getting the same result on a flipped coin
|
||||
$n$ times in a row.
|
||||
|
||||
There is a 93.75% chance that the median of a population
|
||||
is between the smallest and largest values
|
||||
in any random sample of five from that population.
|
||||
@@ -0,0 +1,12 @@
|
||||
# 2026-01-30 18:33:??
|
||||
|
||||
#topic/personal-productivity
|
||||
|
||||
Why is it that I find it so easy, even compulsory,
|
||||
to clean my house while working from home,
|
||||
even after returning from work on-site?
|
||||
Why again does that feeling of necessity
|
||||
persist even into the evening,
|
||||
when I would normally be home anyway,
|
||||
but unable to summon the will to do anything
|
||||
about rapidly growing piles of dirty dishes and clothes?
|
||||
Reference in New Issue
Block a user