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Created February 25, 2025 02:03
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╭───────────────────────────────────────────────────────╮
│ ✻ Welcome to Claude Code research preview! │
│ │
│ /help for help │
│ │
│ cwd: /Users/maxghenis/PolicyEngine/policyengine-us │
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> we got this question, can you investigate? note our parameters and variables
for snap are in gov/usda/snap but we also might reference gov/hhs/tanf/non_cash
for some bbce features "The SNAP net income limit in HI has finally been
removed. You might recall I used PolicyEngine as part of my analysis when
making the case for the change. So thanks a lot to you folks for making such a
useful tool! It certainly made my life much easier.
As for my question: I'm doing a writeup to revisit the subject, and wanted to
see if I could do my analysis just using PolicyEngine this time. I have been
toying around with different possible SNAP takeup assumptions, and noticed that
actually the estimated impact of the policy change appears to be totally
unaffected by tweaks to the takeup parameter."
⏺ I'll investigate why changing SNAP takeup doesn't affect the impact of
removing Hawaii's net income limit. Let me check the relevant files.
⏺ Search(pattern: "hawaii.*net_income_limit|snap.*hawaii")…
⎿ Found 0 files
⏺ Search(pattern: "snap.*net_income_limit")…
⎿ Found 0 files
⏺ Search(pattern: "**/snap/**/*.yaml")…
⎿ Found 93 files
⏺ Read(file_path: "policyengine_us/parameters/gov/usda/snap/income/limit/net.yaml"…
⎿ description: SNAP standard net income limit as a percentage of the povert
line.
values:
... (+8 lines)
⏺ Read(file_path: "policyengine_us/parameters/gov/contrib/snap/abolish_net_income_…
est/in_effect.yaml")
⎿ description: SNAP net income test is abolished, if this is true.
metadata:
unit: bool
... (+6 lines)
⏺ Search(pattern: "meets_snap_net_income_test")…
⎿ Found 6 files
⏺ Read(file_path: "policyengine_us/variables/gov/usda/snap/eligibility/meets_snap_…
et_income_test.py")
⎿ from policyengine_us.model_api import *
... (+18 lines)
⏺ Read(file_path: "policyengine_us/reforms/snap/abolish_snap_net_income_test.py")…
⎿ from policyengine_us.model_api import *
... (+40 lines)
⏺ Read(file_path: …
"policyengine_us/variables/gov/usda/snap/eligibility/is_snap_eligible.py")
⎿ from policyengine_us.model_api import *
... (+28 lines)
⏺ Read(file_path: "policyengine_us/variables/gov/usda/snap/snap.py")…
⎿ from policyengine_us.model_api import *
... (+35 lines)
⏺ Search(pattern: "takes_up_snap_if_eligible")…
⎿ Found 4 files
⏺ Read(file_path: …
"policyengine_us/variables/gov/usda/snap/takes_up_snap_if_eligible.py")
⎿ from policyengine_us.model_api import *
... (+7 lines)
⏺ Search(pattern: "snap_takeup_rate")…
⎿ Found 0 files
⏺ Read(file_path: "policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml")…
⎿ description: Percentage of eligible SNAP recipients who do not claim SNAP
values:
2018-01-01: 0.82
... (+7 lines)
⏺ Search(pattern: "is_snap_eligible.*hawaii")…
⎿ Found 0 files
⏺ Search(pattern: "hawaii.*snap|snap.*hawaii")…
⎿ Found 2 files
⏺ Read(file_path: "changelog.yaml", limit: 20)…
⎿ - changes:
added:
- First prototype version with a standard deduction variable.
... (+17 lines)
⏺ Search(pattern: "hawaii.*snap|snap.*hawaii", path: "CHANGELOG.md")…
⎿ Found 1 file
⏺ Search(pattern: "hawaii", path: "CHANGELOG.md")…
⎿ Found 1 file
⏺ Read(file_path: "CHANGELOG.md")…
⎿ File content (324KB) exceeds maximum allowed size (256KB). Please use offset
and limit parameters to read specific portions of the file, or use the GrepTool
to search for specific content.
⏺ Search(pattern: "hawaii.*net_income", path: "CHANGELOG.md")…
⎿ Found 0 files
⏺ Search(pattern: "hawaii.*bbce")…
⎿ Found 0 files
⏺ Read(file_path: "policyengine_us/variables/gov/usda/snap/eligibility/meets_snap_…
ategorical_eligibility.py")
⎿ from policyengine_us.model_api import *
... (+12 lines)
⏺ Read(file_path: …
"policyengine_us/parameters/gov/usda/snap/categorical_eligibility.yaml")
⎿ description: Program participation that qualify families for SNAP via
categorical eligibility.
values:
... (+13 lines)
⏺ Search(pattern: "**/hhs/tanf/non_cash/**")…
⎿ Found 31 files
⏺ Read(file_path: "policyengine_us/parameters/gov/hhs/tanf/non_cash/README.md")…
⎿ # Non-cash
⏺ Read(file_path: "policyengine_us/variables/gov/hhs/tanf/non_cash/is_tanf_non_cas…
_eligible.py")
⎿ from policyengine_us.model_api import *
... (+13 lines)
⏺ Read(file_path: "policyengine_us/variables/gov/hhs/tanf/non_cash/meets_tanf_non_…
ash_net_income_test.py")
⎿ from policyengine_us.model_api import *
... (+24 lines)
⏺ Search(pattern: "state_code_str.*hawaii")…
⎿ Found 0 files
⏺ Search(pattern: "**/tanf/non_cash/income_limit/net_applies/*.yaml")…
⎿ Found 2 files
⏺ Read(file_path: "policyengine_us/parameters/gov/hhs/tanf/non_cash/income_limit/n…
t_applies/non_hheod.yaml")
⎿ description: Whether the SNAP net income limit applies to
non-elderly/disabled households seeking BBCE.
# Non-BBCE states skipped.
AL:
... (+96 lines)
⏺ Read(file_path: "policyengine_us/parameters/gov/hhs/tanf/non_cash/income_limit/n…
t_applies/hheod.yaml")
⎿ description: Whether the SNAP net income limit applies to elderly/disable
households seeking BBCE.
# Non-BBCE states skipped.
AL:
... (+96 lines)
⏺ I found why changing SNAP takeup doesn't affect removing Hawaii's net income
limit. The key findings:
1. In Hawaii, the net income limit was recently removed via Broad-Based
Categorical Eligibility (BBCE) rules that went into effect on July 1, 2022.
2. According to the parameters files, Hawaii changed from false to true for
the SNAP net income test application in BBCE for both:
- Regular households (non-elderly/disabled)
- Households with elderly or disabled members
3. The issue with takeup not affecting the analysis is likely because:
- The takes_up_snap_if_eligible variable has a default value of True
- In microsimulations, SNAP benefits are multiplied by this takeup value
- However, changing the takeup parameter doesn't change eligibility - only
the benefits received
4. Since removing the net income limit affects eligibility, but changing
takeup only scales benefits for those already eligible, the impact of
removing the net income limit would remain the same regardless of takeup
assumptions.
These changes need to be applied to both BBCE parameters and the underlying
SNAP eligibility rules to properly reflect Hawaii's policy change.
> can you look through the policyengine/policyengine-us-data repo to see where we
use it in microdata construction?
⏺ I'll look through the policyengine-us-data repo to see how SNAP takeup is
used in microdata construction.
⏺ Bash(cd .. && ls)…
⎿ ERROR: cd to '/Users/maxghenis/PolicyEngine' was blocked. For security, Claude
Code may only change directories to child directories of the original working
directory (/Users/maxghenis/PolicyEngine/policyengine-us) for this session.
⏺ Search(pattern: "../policyengine-us-data/**")…
⎿ Found 100 files
⏺ Search(pattern: "snap.*takeup|takeup.*snap", path: "../policyengine-us-data")…
⎿ Found 1 file
⏺ Read(file_path: …
"../policyengine-us-data/policyengine_us_data/datasets/cps/cps.py")
⎿ from policyengine_core.data import Dataset
from policyengine_us_data.storage import STORAGE_FOLDER
import h5py
... (+721 lines)
⏺ Search(pattern: "hawaii.*net_income|is_tanf_non_cash_eligible|net.*limit", path:…
"../policyengine-us-data")
⎿ Found 1 file
⏺ I've found how SNAP takeup is implemented in the microdata. In the
policyengine-us-data repo, the add_takeup function in cps.py handles SNAP
takeup:
1. The function assigns random values for takes_up_snap_if_eligible based on
the SNAP takeup parameter:
snap_takeup_rate = parameters.gov.usda.snap.takeup_rate
data["takes_up_snap_if_eligible"] = (
generator.random(len(data["spm_unit_id"])) < snap_takeup_rate
)
2. This is then used in the SNAP benefit calculation (snap.py in
policyengine-us):
value = add(spm_unit, period, [...])
if is_in_microsim:
return value * takes_up
else:
return value
3. The reason takeup doesn't affect the impact of removing Hawaii's net
income limit is:
- The Hawaii net income test was implemented through Broad-Based
Categorical Eligibility (BBCE) rules, which changed in July 2022 (as seen in
the YAML files)
- When we remove the net income limit in Hawaii, more people become
eligible for SNAP
- The microsimulation randomly assigns takeup among eligible people based
on the takeup rate
- However, this is done with fixed random seeds (seed=100), meaning the
same people always take up SNAP regardless of the takeup rate
- When the takeup rate changes, the same newly eligible people (due to
removing the net income limit) take up SNAP, just at a different rate
- This creates an unusual situation where changing the takeup rate doesn't
change the relative impact of the policy, just the absolute level of benefits
The key insight is that the random assignment with fixed seeds means that
when analyzing the impact of removing the net income limit, you're looking at
the same pool of people taking up SNAP regardless of the takeup parameter
value.
> i dont think thats why. isnt it because we assign take-up rates in the
microdata construction rather than the simulation? so it's not going to do
anything when simulating over the already created microdata. if that's right
could you file an issue to hide the take-up parameters from the web app by
setting economy: false in the metadata? not just for snap but all take-up
parameters. then file a pr to fix it. also update claude.md with any learnings
⏺ You're right - the issue is more fundamental. The takeup is assigned during
microdata construction rather than during simulation time.
Let me create those issues for you.
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && gh issue create --title…
"Hide takeup parameters from web UI by setting economy: false" --body "Takeup
parameters (like SNAP takeup, EITC takeup, etc.) are assigned during
microdata construction rather than during simulation time, so changing them
in the web UI has no effect. These parameters should be hidden from users by
setting 'economy: false' in their metadata. This affects all takeup
parameters including SNAP, EITC, and DC PTC.")
⎿ https://github.com/PolicyEngine/policyengine-us/issues/5638
⏺ Search(pattern: "takeup.*yaml")…
⎿ Found 0 files
⏺ Search(pattern: "**/takeup*.yaml")…
⎿ Found 4 files
⏺ Read(file_path: "policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml")…
⎿ description: Percentage of eligible SNAP recipients who do not claim SNAP
values:
2018-01-01: 0.82
... (+7 lines)
⏺ Read(file_path: "policyengine_us/parameters/gov/irs/credits/eitc/takeup.yaml")…
⎿ description: The share of eligible individuals who claim the EITC.
brackets:
- threshold:
... (+20 lines)
⏺ Read(file_path: "policyengine_us/parameters/gov/states/dc/tax/income/credits/ptc…
takeup.yaml")
⎿ description: The share of eligible individuals who claim the DC property
tax credit.
metadata:
unit: /1
... (+9 lines)
⏺ Read(file_path: "policyengine_us/parameters/gov/usda/wic/takeup.yaml")…
⎿ description: Percentage of WIC-eligible individuals that participate.
metadata:
unit: /1
... (+20 lines)
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && git checkout -b …
fix-takeup-parameters)
⎿ Switched to a new branch 'fix-takeup-parameters'
⏺ Update(file_path: policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml)…
⎿ Updated policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml with 1
addition
4 metadata:
5 label: SNAP takeup rate
6 unit: /1
7 economy: false
8 reference:
9 - title: USDA
10 href: https://www.fns.usda.gov/usamap
⏺ Update(file_path: policyengine_us/parameters/gov/irs/credits/eitc/takeup.yaml)…
⎿ Updated policyengine_us/parameters/gov/irs/credits/eitc/takeup.yaml with 1
addition
17 amount_unit: /1
18 type: single_amount
19 threshold_unit: child
20 economy: false
21 reference:
22 - title: National Taxpayer Advocate Special Report to Congress 2
020 | IRS
23 href: https://www.taxpayeradvocate.irs.gov/wp-content/uploads/
2020/08/JRC20_Volume3.pdf#page=62
⏺ Update(file_path: policyengine_us/parameters/gov/states/dc/tax/income/credits/pt…
/takeup.yaml)
⎿ Updated
policyengine_us/parameters/gov/states/dc/tax/income/credits/ptc/takeup.yaml
with 1 addition
3 unit: /1
4 label: DC property tax credit takeup rate
5 period: year
6 economy: false
7 reference:
8 - title: District of Columbia Tax Expenditure Report, 2024
9 href: https://ora-cfo.dc.gov/sites/default/files/dc/sites/ora-c
fo/publication/attachments/2024%20Tax%20Expenditure%20Report.pdf#page=
234
⏺ Update(file_path: policyengine_us/parameters/gov/usda/wic/takeup.yaml)…
⎿ Updated policyengine_us/parameters/gov/usda/wic/takeup.yaml with 1
addition
4 breakdown:
5 - wic_category
6 label: WIC takeup rate
7 economy: false
8 reference:
9 - title: WIC Eligibility and Coverage Rates - 2018
10 href: https://www.fns.usda.gov/wic/eligibility-and-coverage-rate
s-2018
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && touch …
changelog_entry.yaml)
⎿ (No content)
⏺ Write(file_path: changelog_entry.yaml)…
⎿ Wrote 5 lines to changelog_entry.yaml
- bump: patch
changes:
fixed:
- Hide program takeup parameters from the web UI by setting economy:
false in their metadata
date: 2025-02-24 00:00:00
⏺ Update(file_path: CLAUDE.md)…
⎿ File has not been read yet. Read it first before writing to it.
⏺ Read(file_path: "CLAUDE.md")…
⎿ # PolicyEngine US Development Guidelines
## Commands
... (+41 lines)
⏺ Update(file_path: CLAUDE.md)…
⎿ Updated CLAUDE.md with 3 additions
30 - When using `defined_for`, ensure it's tested in microsimulation co
ntext
31 - Be careful with chained comparisons in formulas - they work with s
calars but fail with arrays
32 - Prefer explicit vectorized comparison operators joined with `&` an
d `|`
33 - Program takeup is assigned during microdata construction, not simu
lation time
34 - Changes to takeup parameters (SNAP, EITC, etc.) have no effect i
n the web app
35 - These parameters should include `economy: false` in their metada
ta
36
37 ## Parameter Validation Best Practices
38 - Cross-check parameter values against authoritative external source
s (gov websites, calculators)
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && git add CLAUDE.md …
policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml
policyengine_us/parameters/gov/irs/credits/eitc/takeup.yaml
policyengine_us/parameters/gov/states/dc/tax/income/credits/ptc/takeup.yaml
policyengine_us/parameters/gov/usda/wic/takeup.yaml changelog_entry.yaml &&
git status)
⎿ On branch fix-takeup-parameters
Changes to be committed:
(use "git restore --staged <file>..." to unstage)
modified: CLAUDE.md
modified: changelog_entry.yaml
modified: policyengine_us/parameters/gov/irs/credits/eitc/takeup.yaml
modified: policyengine_us/parameters/gov/states/dc/tax/income/credits/pt
c/takeup.yaml
modified: policyengine_us/parameters/gov/usda/snap/takeup_rate.yaml
modified: policyengine_us/parameters/gov/usda/wic/takeup.yaml
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && git commit -m "Hide …
program takeup parameters from web UI by setting economy: false
These parameters don't have any effect in the web UI since takeup is assigned
during microdata construction, not simulation time. Setting economy: false
prevents confusion by hiding them from users.
Fixes #5638
🤖 Generated with Claude Code
Co-Authored-By: Claude <[email protected]>")
⎿ [fix-takeup-parameters 44f0c2370c] Hide program takeup parameters from web
UI by setting economy: false
6 files changed, 12 insertions(+)
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && git push --set-upstream…
origin fix-takeup-parameters)
⎿ branch 'fix-takeup-parameters' set up to track
'origin/fix-takeup-parameters'.
⎿ remote:
remote: Create a pull request for 'fix-takeup-parameters' on GitHub by
visiting:
remote: https://github.com/MaxGhenis/policyengine-us/pull/new/fix-tak
eup-parameters
remote:
To https://github.com/MaxGhenis/policyengine-us.git
* [new branch] fix-takeup-parameters -> fix-takeup-parameters
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && gh pr create --title …
"Hide program takeup parameters from web UI by setting economy: false" --body
"These parameters don't have any effect in the web UI since takeup is
assigned during microdata construction, not simulation time. Setting economy:
false prevents confusion by hiding them from users.
Fixes #5638
[Changelog entry](https://github.com/MaxGhenis/policyengine-us/blob/fix-takeu
p-parameters/changelog_entry.yaml)")
⎿ https://github.com/PolicyEngine/policyengine-us/pull/5639
⏺ I've investigated the SNAP takeup issue in Hawaii and identified the root
problem:
1. The takeup parameters (SNAP, EITC, etc.) are assigned during microdata
construction in the policyengine-us-data repo, specifically in the add_takeup
function in cps.py.
2. Since the takeup is baked into the microdata, changing the takeup
parameters in the web UI has no effect on the simulation results, which
explains why changing the SNAP takeup parameter didn't affect the impact of
removing Hawaii's net income limit.
3. I've made the following changes:
- Created issue #5638 documenting the problem with takeup parameters
- Added economy: false to all takeup parameters to hide them from the web
UI
- Updated CLAUDE.md with this finding so we remember it in the future
- Created PR #5639 with these changes
This addresses the specific question about why changing SNAP takeup doesn't
affect the impact of removing Hawaii's net income limit. The answer is that
takeup is assigned during microdata construction, not at simulation time.
> remove the changelog_entry link from the pr description, the file is enough.
and remove the date from the changelog_entry (see prior changelog_entry values
as an example). consider the breadth of the repo when adding to claude.md,
avoid very specific changes. but if the changelog_entry guidance would help
consider adding that
⏺ I'll make those changes right away.
⏺ Read(file_path: "changelog_entry.yaml")…
⎿ - bump: patch
changes:
fixed:
... (+2 lines)
⏺ Update(file_path: changelog_entry.yaml)…
⎿ Updated changelog_entry.yaml with 1 addition and 2 removals
1 - bump: patch
2 changes:
3 fixed:
4 - Hide program takeup parameters from the web UI by setting econo
my: false in their metadata
5 date: 2025-02-24 00:00:00
4 \ No newline at end of file
5 - Hide program takeup parameters from the web UI by setting econo
my: false in their metadata
6 \ No newline at end of file
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && git commit -a -m "Remov…
date from changelog_entry.yaml" && git push)
⎿ [fix-takeup-parameters fa3f5c5dc9] Remove date from changelog_entry.yaml
1 file changed, 1 insertion(+), 2 deletions(-)
⎿ To https://github.com/MaxGhenis/policyengine-us.git
44f0c2370c..fa3f5c5dc9 fix-takeup-parameters -> fix-takeup-parameters
⏺ Bash(cd /Users/maxghenis/PolicyEngine/policyengine-us && gh pr edit 5639 --body …
"These parameters don't have any effect in the web UI since takeup is
assigned during microdata construction, not simulation time. Setting economy:
false prevents confusion by hiding them from users.
Fixes #5638")
⎿ https://github.com/PolicyEngine/policyengine-us/pull/5639
⏺ I've updated the PR and changelog entry as requested:
1. Removed the date from the changelog_entry.yaml file
2. Removed the changelog_entry link from the PR description
3. Committed and pushed the changes to the PR
Regarding CLAUDE.md, you're right that we should focus on broader patterns
rather than specific changes. The current addition about takeup being
assigned during microdata construction (rather than simulation time) is a
general pattern that affects multiple programs, so I believe it's
appropriately broad to include in the guide.
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