SSI version 39.4 Version History

The TRIM3 SSI module simulates the operation of the Supplemental Security Income program, which provides cash payments to low-income elderly, blind, and disabled persons. The module simulates both the basic federal portion of the program and many of the optional supplementary payments provided in some states. The eligibility and benefits are calculated for each month. As in the actual program, a person whose income varies throughout the year is eligible for different amounts of SSI in different months. However, a unit’s participation decision is made once for the entire year.

The TRIM3 SSI module performs detailed eligibility and benefit computations for non-institutionalized aged persons and disabled adults. TRIM3 does not model benefits to institutionalized persons (5.2 percent of the caseload in December 1996) because the CPS does not sample from the institutionalized population. TRIM3 simulates the children's portion of the SSI program (14 percent of the federal SSI caseload in December 1997) but the modeling capabilities are more limited than for adults. Because the CPS does not ask questions about children's disability, TRIM3 can not estimate the number of children eligible for SSI. However, TRIM3 does select a caseload of children who meet financial eligibility requirements and who match the actual children's SSI caseload in size and characteristics; and TRIM3 performs a detailed calculation of their benefits.

The simulation of SSI is divided into five main steps: Identifying potential units and determining whether or not each unit’s members meet the age and disability requirements of SSI; Computing the resources of each unit and comparing them to a specified limit; Calculating earned and unearned income, the amount of income disregarded when calculating benefits, and the amount of income from an ineligible spouse or parent which is deemed available to a unit; Calculating the federal benefits and state supplements for which each unit is eligible; and Deciding which eligible units will actually participate in the SSI program. This documentation describes each of these steps in detail, as follows:

• Categorical Eligibility
• Eligibility Due to Age
• Eligiblity Due to Disability or Blindness, Persons 15 and Older
• Children
• Citizenship Determination
• Output Variables
• Asset Test
• Output Variables
• Income Determination
• Unearned Income
• Earned Income
• Deeming of Income
• Output Variables
• Benefit Determination
• Federal and State Benefit Standards in TRIM3
• Benefit Reductions for Units Living in Another's Home
• Benefit Calculation
• Deeming Considerations
• Output Variables
• Participation Decision
• Calculating the Probability of Participation
• Calculating the Participation Random Number
• Purpose of the Participation Random Number
• An Example
• NonReporterAdjustment Form
• Output Variables

Special sections include additional information about the simulation process:

• Running an Alternative Simulation
• Processing Children Under 15
• Initial Selection of Potential Disabled Children
• Selecting Potential Disabled Children
• Output Variables
• Baseline vs. Alternative Simulations
• Reporter Status
• Selecting Persons as Reporters
• Selecting Reporter Units

Categorical Eligibility

A person can be categorically eligible for SSI by reason of age or disability. TRIM3 first divides people into potential SSI units. A unit is either a married couple or a single person. The module then determines whether each person is categorically eligible for SSI based on age, disability, or both, and assigns each unit to one of the following types:

• married couple, both aged
• married couple, both disabled
• married couple, one aged, one disabled: treat as aged unit
• married couple, one aged, one disabled: treat as disabled unit
• married couple, one aged, other ineligible
• married couple, one disabled, other ineligible
• unmarried aged adult
• unmarried disabled adult
• disabled student 18-21 (considered a child prior to 1997)
• disabled child 15-17 (economic adult on CPS)
• disabled child < 15 (disability is assigned)
• disabled child, SSI reported on their behalf by parent

If a person is both aged and disabled, s/he is considered to be aged in the simulations. Due to the methods used to determine categorical eligibility, a unit is either categorically eligible for SSI for the entire year, or not categorically eligible for that year; the categorical eligibility status does not vary over the months of the year. Of course, due to income and assets tests, a unit may be financially eligible for benefits in some months but not all.

Note that throughout this document, "unmarried" and "married" are used to describe the marital status of the person(s) in an SSI unit, while "single" and "double" are used to refer to the number of eligible persons in a unit. Units composed of a married couple in which both members of the couple are eligible and living together are double, while the remaining unit types are single. A person with single eligibility may be married or unmarried. Although the administrative rules for SSI may treat someone as married even if s/he is not presently living with the spouse, the model uses married to mean "married, spouse present" since we have no information on the income, assets, or demographic characteristics of a non-present spouse.

Eligibility due to Age

An individual is categorically eligible if his/her age is at least equal to the age specified in the program rule (MinimumEligibleAge). In the actual SSI program, persons are considered aged at 65. Note that someone who is the exact age limit in March of one year was eligible for at most nine months of the prior year. However, allowing these individuals to be eligible for the entire prior year compensates for the fact that some others who were eligible in the prior year are not in the March sample because they have died.

Eligibility due to Disability or Blindness, Persons 15 and Older

SSI regulations define disability as being "unable to engage in substantial gainful activity by reason of a medically determined physical or mental impairment expected to result in death or that has lasted, or can be expected to last, for a continuous period of at least 12 months." Blindness is defined based on specific criteria involving visual acuity and field of vision. In order for an individual to qualify for SSI due to either disability or blindness (as opposed to qualifying based on being elderly) earnings cannot exceed a specific dollar amount that is defined as substantial gainful activity (SGA); there are different dollar amounts for individuals qualifying due to blindness and those qualifying due to other disability.

Prior to the March 2008 CPS (2007 input year) disability and vision information was not directly reported in the CPS, and therefore TRIM3 had to infer this information from other variables. Even when disability information is available, TRIM3 still looks at other variables (as well as the disability variables) in order to accurately identify disability. Specifically, TRIM3 looks for people who report that they were not working because they were ill or disabled, for people who received types of income that indicate they were disabled, and people who indicate some type of activity limitation as follows:

1) For individuals who did not work at all during the calendar year, one of the following conditions must be met in order for the person to be considered disabled:

2) Individuals with some earnings during the calendar year are only checked for disability if the program rule SubstantialGainfulActivityOption is set to "test for substantial gainful activity". If it is, then a person with some earnings during the calendar year is considered disabled if BOTH of the following conditions are met:

The kinds of income that indicate disability, and the circumstances under which they indicate disability, are as follows:

• Reports of SSI that were "allocated" are not used to infer disability
• If the rule ReporterOption is set to "expanded reporter definition," then those persons who have reported SSI receipt, but have given the reason for receipt to be only that it was on the behalf of a child (program rule ReasonForSSI) and the reason was not allocated (program rule AllocFlagReasonForSSI), are not considered to be disabled.

(Note that a widow or a person under age 22 may be receiving veterans payments or Social Security/Railroad Retirement due to being the surviving spouse or child of a person covered by those programs, rather than due to his/her own disability.)

Several additional points are important to note:

1. If the program rule SubstantialGainfulActivityOption is set to "no test", no individuals with any earnings will be identified as disabled. Users may choose this option to model a more stringent disability definition, or to create simulations consistent with TRIM simulations produced prior to the capability of modeling the SGA test.
2. Persons who are blind cannot be separately identified. However, the definitions of disability should capture most blind people who are not working because of their blindness. For individuals identified by the above definitions who have some earnings, the SubstantialGainfulActivity value for disabled people is always used; the value for blind people is included in the database for information only.
3. Due to the methods for identifying disability, the only elderly people who can be identified as also being disabled are those who report not having worked at all during the calendar year and either give "illness or disability" as the reason or have some type of activity limitation.

Children

The SSI program defines a child generally to be "not married, not the head of a household, and either under age 18 or under 22 and a student". However, for the purposes of determining which of these persons should actually be classified as children for various aspects of the SSI program, only a subset of those identified by the general definition are considered to be children. The rules ChildAgeCutoffForUnitType, ChildAgeCutoffForDeeming, and ChildAgeCutoffForAllocations specify which subsets are to be used for each of these areas.

Some persons categorized as "children" by SSI are considered "economic adults" by the CPS. These are persons 15 or older. The CPS supplies income and employment information for all economic adults. As described in the previous section Eligibility due to Disability or Blindness, Persons 15 and Older, TRIM3 makes use of this information to determine if a person is disabled. Since this information is not available for children who are not economic adults, an alternative method is used to determine whether such children should be considered disabled. As described in a later section (Processing Children Under 15), the method used allows us to simulate only those non-economic-adult children who actually receive SSI, and not those who are eligible but not receiving SSI.

Additionally, if the rule ReporterOption is set to "expanded reporter definition," then children with ChildReceivedSSI equal to 1 where the value is not allocated (program rule AllocFlagChildRecvSSI), are considered to be disabled and are not included in the alternate method described in the section, Processing Children Under 15.

Citizenship Determination

The program rules LegalAlienEligible, TempAlienEligible, IllegalAlienEligible, RefugeeEligYears, and ExtendedRefugeeEligYears determine whether or not non-citizens are simulated as eligible to receive SSI. LegalAlienEligible, TempAlienEligible and IllegalAlienEligible all indicate whether legal aliens, temporary aliens or illegal aliens are ever eligible. RefugeeEligYears specifies the maximum number of years (of U.S. residence) a refugee/asylee may be eligible; and ExtendedRefugeeEligYears specifies an additional number of years minor (age <18) and elder (age 70+) refugees may be eligible for SSI beyond the years specified by RefugeeEligYears.

Persons found to be ineligible because of their citizenship status are treated the same as persons found ineligible because they are not categorically eligible (i.e. not aged or disabled). In other words, if the ineligible person is the spouse of an eligible person, their income is deemed to the eligible spouse, but if the ineligible person would normally be a single-person unit they simply become a categorically ineligible unit. Currently, citizenship-related eligibility rules can only be implemented when the input data contains the variable CorrectedCitizenship. In SSI simulations done with input data not containing that variable (currently all data before 1997) values of these rules are assumed to be 0, making no people ineligible for SSI because of their citizenship status. More details are available here.

If non-citizens should not be found ineligible due to sponsor deeming when the sponsor is in the same unit as the non-citizen then the AlienPrep output variable SponsorID must be specified in the variable list rule SponsorID.

Output Variables

Information on a particular person’s categorical eligibility is stored in the output variables MonthlyPersonEligType and AnnualPersonEligType, while information on the categorical eligibility of the person’s unit is stored in the output variables UnitType and AnnualUnitType. Information on the aged/disabled status of each person (regardless of whether they pass the citizenship tests) is stored in the output variables MonthlySSIAgedDisabledStatus and AnnualSSIAgedDisabledStatus. Note that a person can be aged and/or disabled but not categorically eligible if they fail the citizenship tests.

Other information regarding the composition of the unit can be found in the variables AnnualUnitSize, UnitSize, AnnualHead, Head, AnnualSpouse, Spouse, AnnualUnitWeight and UnitWeight. Unit-level variables are written to each person in the unit, even if the person is an ineligible member of the unit (i.e. an ineligible spouse).

Asset Test

A categorically eligible SSI unit becomes automatically ineligible for benefits if the value of the unit's resources exceeds an established limit. In the administration of the program, resources are &guot;cash or other liquid assets or any real or personal property that an individual (or spouse, if any) owns and could convert to cash to be used for his support and maintenance". Certain resources are excluded from consideration, including the entire value of the unit’s home (prior to October 1976, only the portion of the value under a certain limit was excluded), household goods and personal effects, the value of a car under a certain limit, etc.

The maximum value of assets that a unit may have and still retain SSI eligibility varies by the marital status of the person(s) in the unit, not by the number of eligible persons. An unmarried person who is categorically eligible has a different limit on countable resources than married couples (see rules AssetLimitSingle and AssetLimitCouple).

In TRIM3, the value of a unit’s assets are determined monthly. Since TRIM3 input files do not generally contain information on the value of a unit’s assets, an assumed rate of return (specified by rule AssetRate) is used to estimate the amount of assets that would generate the monthly asset income reported via the rule AssetIncome. For example, if in a month a unit reports $100 in asset income, and the rate of return is set to 0.06, the unit is assumed to have $20,000 in assets ($100 multiplied by 12, divided by .06).

Under actual program rules, a portion of a parent’s assets is "deemed available" to a disabled child in determining whether or not the child passes the assets test. TRIM3 does not simulate this rule.

Output Variables

The result of the estimation of the value of a unit’s assets is contained in the variable SimulatedUnitAssets, while information about whether this estimated amount is within the allowable limits is in the variable SSIPassedAssetTest. Unit-level variables are written to each person in the unit, even if the person is an ineligible member of the unit (i.e. an ineligible spouse).

Income Determination

Income is "anything you receive in cash or in-kind that you can use to meet your needs for food, clothing, or shelter," with some exceptions such as: income tax refunds, cash provided as reimbursement for the purchase of medical services, etc. A certain amount of unearned and earned income is disregarded from the total. Some of the income of ineligible spouses and parents is "deemed available" to the eligible person and added to their personal income or allocated from eligible units to ineligible units.

Unearned Income

Unearned income includes private and government pensions, Social Security, veterans benefits, workers compensation, unemployment compensation, interest, dividends, rents, AFDC payments, and certain other income such as prizes and awards, gifts and inheritances, and proceeds of life insurance policies. Means-tested cash benefits are excluded if they are "wholly funded by a state or one of its political subdivisions," but not if they are paid under a federal/state grant program. Therefore, AFDC income is counted, but general assistance income is not. Several means-tested non-cash benefits are specifically excluded from consideration, including SNAP, other nutrition assistance (school lunches), the value of public housing, and the value of energy assistance.

In TRIM3, all but one (child support income) of the types of income which should be counted as unearned are defined by the program rule UnearnedIncomeComponents. The sum of these components is reduced by an amount of unearned income to disregard (see rule DisregardUnrestrictedIncome). Child support income is specified separately via the rule ChildSupportIncomeOfChild. This amount is reduced by the amount specified by the rule PercentChildSupportDisregarded before it is added to total unearned income.

The CPS does not permit us to precisely capture unearned income, for at least three reasons. First, unearned income may be slightly overstated because the CPS variable "OTHR" includes some items (such as educational grants) which are not counted as income by SSI. Second, the unearned income of blind and disabled eligibles may be somewhat overstated because TRIM3 cannot simulate the SSI provision that subtracts the cost of an "approved plan to achieve self-support." Third, TRIM3 does not model the "presumed value" rule. When a unit receives in-kind support but does not live in the household of another person, the support is presumed to be worth one-third of the value of the benefit standard, unless the unit shows that the in-kind assistance is worth less. Because TRIM3 input files do not include information on whether in-kind support is received, this rule is not simulated, and therefore the unearned income of some units may be understated. These simplifications in the counting of unearned income are not significant problems, since relatively few units receive the types of income involved.

The inclusion of AFDC in unearned income creates some circularity problems, since SSI status affects AFDC benefits--SSI recipients are excluded from the AFDC unit. Generally, the SSI module is run first, using reported rather than simulated AFDC benefits. Then, the AFDC module is run, using the simulated SSI benefits.

Earned Income

Prior to version 34.0, SSI used a single rule--EarnedIncomeComponents--to designate earned income variables, whether wage and salary earnings or self-employment earnings. In version 34.0, a new rule--SelfEmpIncomeComponents--was added so that self-employment earnings could be treated differently from wage and salary earnings. Users determine at the time of simulation setup which allocation method is used with each of these rules to allocate annual income amounts to months of the year. Typically, wage and salary earnings are allocated by weeks worked during the year, whereas self-employment income is allocated equally to all months.

If a user supplies a value for program rule EmployerShareOfPayrollTaxes, self-employment income contained in SelfEmpIncomeComponents is reduced by the fraction provided. Output variable NetEarningsFromSelfEmployment is computed as the sum of variables in SelfEmpIncomeComponents * (1-EmployerShareOfPayrollTaxes).

For each month, if the sum of that month's earned income from both wage and salary earnings and self-employment is less than zero, it is set to zero. Each month's earned income may be further reduced by an amount of earnings to disregard (see rules DisregardUnrestrictedIncome, DisregardEarnedIncome, and ProportionEarningsDisregarded).

TRIM3 may slightly over-count earned income for some people because it cannot capture some disregards applied to earned income. Namely, blind and disabled eligibles can disregard some income used to pay work expenses, or used "to fulfill an approved plan to achieve self-support." Small amounts of irregular or infrequent earned income are disregarded for all eligibles. TRIM3 may slightly undercount earned income by not capturing any earnings received in-kind, which are technically included by SSI in earned income. TRIM3 does not simulate the rules that allow disabled children additional earned income disregards. Since the only disabled children that TRIM3 can identify are not working, this rule is not applicable to the model.

If PolicyOption is set to "Deduct Child Support paid from available income", the amount of available income - which is unearned income plus earned income minus disregards from earned/unearned income - is further reduced by the amount of child support paid to a non-resident child by all eligible persons in the unit. Program rule CSPaidByNRP contains monthly child support paid.

Deeming of Income

According to the SSI regulations, "We deem income because we expect your ineligible spouse or ineligible parent with whom you live to use part of his or her income to take care of some of your needs." Deeming involves calculating the total countable income of the parent(s) or spouse, applying disregards, making allocations for the support of ineligible children in the household, and then deeming a portion of the remainder to be available to the SSI unit.

When the unit includes an ineligible spouse, the steps in deeming are as follows:

1. The countable income of the ineligible spouse is computed. This differs from the income definition used for the eligible person, in that neither public income maintenance payments nor "any income which was counted or excluded in figuring the amount of that payment" is included. Rather than trying to determine what income was used in the other program's benefit computation, TRIM3 simply does not deem income from someone who receives any public income maintenance payments. The rule PublicAssistanceIncome lists the types of income that count as public income maintenance payments for this purpose -- generally AFDC, general assistance (GA), and veterans benefits. Although there is evidence that GA benefits reported on surveys are often confused with AFDC benefits, we are not concerned about using the reported general assistance to indicate receipt of public assistance, since even if the reported GA is actually AFDC, the ineligible spouse should still be exempt from deeming.
2. Disregards are applied to the countable income. The unrestricted disregard (rule DisregardUnrestrictedIncome) can only be applied once; if it has already been used for the eligible person, it cannot be used again. The other disregards (rules DisregardEarnedIncome, and ProportionEarningsDisregarded) can be applied without restriction. However, to simplify processing, all of the disregards are applied only once to the eligible unit’s income, after any deemed income has been added to the eligible spouse’s income.
3. Some of the ineligible spouse's countable income is set aside to cover the needs of any ineligible children in the family. An ineligible child is a child under the age specified by rule ChildAgeCutoffForAllocations, who is not disabled, and who does not receive public income maintenance payments (as specified by the rule PublicAssistanceIncome). The amount of income allocated to the ineligible child is the difference between the federal benefit standard for couples (rule IncomeGuaranteeCouple) minus the benefit standard for single adults (rule IncomeGuaranteeSingle), less the earned and unearned income of the child. The total amount allocated to ineligible children is subtracted first from countable income and then from earned income.
4. The child support paid by the ineligible spouse to a non-resident child (specified by CSPaidByNRP) is deducted from the available income, if PolicyOption is set to "Deduct Child Support paid from available income".
5. If the final result of all these adjustments is greater than the difference between the federal guarantee for a couple and for a single, it is deemed available to the eligible individual AND the unit is treated as a couple. Note that the amount of benefits for which the unit is eligible when deeming is applied is not permitted to exceed the benefits for which the unit would be eligible if deeming wasn’t applied. This is discussed in the section Benefit Determination.

When the unit is a child, if the child is living with his/her parents, it's possible that some of the parents' income can be deemed to the child. (Note: the program rule DeemingForChildren allows the user to turn off all deeming from parents to children). If a child is living with a non-parent caretaker (such as a grandparent, aunt or uncle, etc.) no deeming is performed. The steps for deeming income from parents are:

1. The countable income of the parents is computed. If a parent is receiving public assistance income, no income is deemed from that parent. The income variables considered to be "public assistance" by TRIM are specified through the program rule PublicAssistanceIncome. (Note: if either parent receives public assistance income, TRIM assumes that both receive it, in which case no income will be deemed from either parent). Also, if a parent is simulated as receiving SSI income, no income is deemed from that parent (although income can still be deemed from the other parent.) For those parents not excluded based on the above criteria, TRIM determines their total earned and unearned income (as specified by the program rules EarnedIncomeComponents and UnearnedIncomeComponents).
2. The parents' earned and unearned amounts are reduced by the SSI income disregards. The unrestricted disregard (rule DisregardUnrestrictedIncome) can only be applied once; if it has already been used for the eligible person, it cannot be used again. The other disregards (rules DisregardEarnedIncome, and ProportionEarningsDisregarded) can be applied without restriction. However, since most child units have no income of their own, TRIM3 does not limit the unrestricted disregard.
3. Earned and unearned income of the parents is further reduced by an allocation for the parents themselves. This allocation is equal to the federal guarantee for a couple if both parents are present, and the guarantee for an individual if only one parent is present (or if both parents are present but one was excluded due to receipt of SSI, as described above).
4. Some of the parents’ countable income is set aside to cover the needs of any ineligible children in the family. For each child (other than the one being considered for SSI eligibility) in the family who is not receiving public assistance income (as specified by the program rule PublicAssistanceIncome) and is not simulated as receiving SSI, TRIM allocates an amount equal to the federal guarantee for a couple minus the federal guarantee for a child. This flat amount is reduced by any income the child might have (specified by the program rules EarnedIncomeComponents and UnearnedIncomeComponents). The total income allocated in this manner for other children in the family is deducted first from the parents' unearned income, and then any remaining allocation is deducted from the parents' earned income.
5. The child support paid by parents to a non-resident child (specified by CSPaidByNRP) is deducted from the available income, if PolicyOption is set to "Deduct Child Support paid from available income".
6. The income remaining after this allocation is deemed available to the child. The deemed income is considered unearned income to the child (even if all or part of the income was the parents' earned income).

Output Variables

The result of calculating the unit’s income is stored in the variable SimulatedAvailableIncome. If any income was deemed to the unit, that amount is stored in MonthlyAmountOfIncomeDeemed and AnnualAmountOfIncomeDeemed. Note that during the determination of benefits for units where income was deemed from an ineligible spouse, if deeming results in higher benefits than not deeming, the value of SimulatedAvailableIncome will be modified to not include deemed income, and the variables MonthlyAmountOfIncomeDeemed and AnnualAmountOfIncomeDeemed will be set to 0. Unit-level variables are written to each person in the unit, even if the person is an ineligible member of the unit (i.e. an ineligible spouse).

Benefit Determination

The SSI program guarantees that no participating aged or disabled unit will have income below a federally-established income floor. However, in most circumstances, when a unit lives in another person's household, the federal guarantee is reduced by one-third, because the unit is assumed to be receiving in-kind support from the rest of the household. States may raise the income floor for their state for certain types of SSI units. Approximately half the states choose to do this by providing supplements for units living in households (as opposed to institutional or other supervised arrangements). The benefit received by a unit is simply that unit's federal guarantee, plus any state supplement, minus the unit's available income. Note that some special rules apply to calculating the benefits of persons who also received benefits under the pre-1974 state aid programs, but because of the very small number of persons involved (9,400 in 1985) these rules are not modeled.

Federal and State Benefit Standards in TRIM3

The federal benefit standard for units with one eligible member differs from the standard for units with two eligible members (see rules IncomeGuaranteeSingle and IncomeGuaranteeCouple). Each of these is reduced by one-third if the SSI unit lives in another's home (described below). This reduction is fixed rather than being allowed to vary.

The SSI program rules StateSupplementSingleOwnHome and StateSupplementCoupleOwnHome give the state supplement to the federal benefit standard for single and double units living in their own home, and the rules StateSupplementSingleOtherHome and StateSupplementCoupleOtherHome for single and double units living in another's home. The rule StateSupplementChildUnit gives the state supplement for a disabled child. You can turn off State SSI supplements for children (see rule NoSupplementForChildren).

Although some states vary their supplements by whether a unit is aged or disabled, TRIM3 does not yet incorporate this detail; when a state's supplements differ by reason for eligibility, an average figure for aged and disabled units is used for all units. State supplements may also vary with a unit's specific location and living circumstances. When a state has different supplements for some counties or areas of the state, an average supplement is coded.

Program rule ProbTakeStateSup contains a probability for each state that determines the number of units selected to take a state supplement. If a unit is eligible for state supplements and federal benefits, the unit takes the state supplement when a random number assigned the unit is less than or equal to the state probability. The result variable TakeStateSup indicates whether or not a unit takes the state supplement.

The special supplements that most states pay to persons living in domiciliary care (protective, supervised, or group living for persons who cannot live alone) are not simulated, for two reasons. First, the only means of identifying the units would be to assume that all those in group homes were in domiciliary care. Second, since states often pay all or part of the supplement directly to the facility providing the services, it is not income to the SSI unit in the same sense as other SSI benefits. State supplements provided to persons in institutions are not relevant to the model, since the CPS represents the non-institutionalized population only.

PolicyOptions 6 allows to add on to the income guarantee an amount equal to the smaller of the dollar amount specified in PolicyOptionValue1 or the percentage of the unit's shelter costs specified in PolicyOptionValue2. Shelter costs have to be provided through variable list rule MonthlyShelterCosts.

PolicyOptions 7 allows analysts to reduce the federal benefit standard of the second to last disabled single-person units in households where there are multiple disabled single-person units by the multiplicative factor in FedIncGuaranteeReductionFactor. FedIncGuaranteeReductionFactor is a value ranging from 0 to 1 that is multiplied by the federal benefit standard only when PolicyOptions 7 is specified.

PolicyOptions 8 enables analysts to impose a maximum on federal benefits for households containing multiple disabled one-person units.

PolicyOptions 9 adds the value stored in either PolicyOptionValue1 (for one-person units) or PolicyOptionValue2 (for 2-person units) to the federal benefit standard if the unit contains the parent(s) of a child under the age of 18.

Benefit Reductions for Units Living in Another's Home

The federal benefit standard is reduced by one-third if the SSI unit lives in another person's household, receiving both food and shelter from that person without paying a pro rata share of household operating expenses. If the "other" person is a spouse, or a parent, then this rule does not apply. Instead, a portion of the income of the spouse or parent is deemed to the unit, as described above under Income Determination. If all of the others in the household receive public income maintenance payments -- AFDC, GA, veterans benefits -- then the rule does not apply, presumably if the others are receiving those payments, they are too poor to be able to help out the SSI unit. In December 1997, 4.1 percent of the SSI caseload receiving federally-administered benefits had been classified as living in the home of another.

In the TRIM3 SSI module, a person who is the head of household, spouse of the head, unrelated to the head, or living in a group home, is always considered to be living in his/her own home. A person who is related to the head of household may be considered to be living in the home of another. However, children units are never considered to be living in the home of another. If everyone else in the household receives some public income maintenance income according to the rule PublicAssistanceIncome, then the home-of-another rule is not applied.

During testing of the module, we found that applying the home-of-another rule to all related non-heads and non-spouses resulted in too many benefit reductions. Therefore, only those related non-heads with $0 income (as specified by the rules EarnedIncomeComponents and UnearnedIncomeComponents) are considered to receive the in-kind support that is the rationale for the benefit reduction. (The $0 amount is not currently parameterized.) The number of persons treated as living in the home of another can be further reduced by reducing the value in the program rule HomeOfAnotherReductionProb. Only this portion of units meeting the other tests for being in the home-of-another are actually considered to be in the home-of-another. The rule HomeOfAnotherOption allows the user to control whether this rule is applied on an annual or monthly basis. The default is to perform it on an annual basis (although before version 17 it was always done on a monthly basis).

Benefit Calculation

The unit's total benefit equals the sum of the appropriate federal and state benefit standards, minus the result of all of the income calculations. If the result is greater than zero, the unit is eligible for a benefit. The monthly federal benefit equals the federal guarantee minus the available income, and the state benefit is the difference between the total and the federal benefits. Note that it is possible for a unit to be eligible for no federal benefits, but eligible for state supplements. Monthly benefit amounts are rounded down to the next lower dollar.

Deeming Considerations

If any income from an ineligible spouse was deemed available to an eligible spouse, the total unit benefits with deeming must be compared to benefits without deeming. Total benefits with deeming is the sum of the state and federal guarantees for a couple unit minus the unit’s available income taking into account deeming. Total benefits without deeming is the sum of the state and federal guarantees for a single unit minus the unit’s available income without taking into account deeming. If total benefits without deeming are less than with deeming, the benefits and available income are set to their non-deeming values.

Output Variables

The total benefit which a person is eligible for is stored in the variables MonthlySSIBenefitsEligibleFor and AnnualSSIBenefitsEligibleFor. The portion of total benefits which is attributable to the federal guarantee as opposed to the state’s supplement is stored in the variables MonthlyFederalBenefitsEligFor and AnnualFederalBenefitsEligFor. Note that all these variables indicate the per-person benefit rather than the unit’s total benefit. The former is calculated by dividing the unit’s benefit by the number of eligible persons in the unit. The latter can be calculated from these variables by summing them for all persons in the unit. Note that these per-person benefit variables are stored only on the records of eligible members of the unit (i.e. nothing is written to the record of an ineligible spouse, even if the eligible spouse is eligible for benefits).

If a unit is eligible for positive benefits in a given month, the unit is considered "eligible" for SSI. The variable SSIMonthsEligible indicates the total number of months a unit is eligible for SSI.

Information regarding whether a benefit reduction was applied to the unit is stored in the variables MonthlyBenefitReductionType and AnnualBenefitReductionType. Currently the only benefit reduction that can be applied is the "living in the household of another" reduction.

Note that if the benefit calculated when deeming from an ineligible spouse proved to be greater than the benefit without deeming, the variable SimulatedAvailableIncome is reset to exclude the deemed income, and the variables MonthlyAmountOfIncomeDeemed and AnnualAmountOfIncomeDeemed are set to 0.

Unit-level variables are written to each person in the unit, even if the person is an ineligible member of the unit (i.e. an ineligible spouse).

The Participation Decision

If a unit is simulated to be eligible for SSI, the next step is to decide if the unit will actually participate in the SSI program. The participation method for SSI has three important features:

1. Eligible units that reported receiving SSI in their CPS interviews will always participate in the baseline simulation.
2. Baseline participating units are selected in a way that meets administrative targets for numbers of units by federal benefit level, state of residence, and citizenship status.
3. In an alternative simulation, if a unit becomes eligible for a higher/lower benefit than in the baseline, it may start/stop participating. Alternatively, the user may specify that the participation decision is to be identical to the decision made in the baseline (see the ruleParticipationOption).

The user can control the probability of participation a unit will face. SSI program rules allow probabilities to vary by unit type and benefit level, and allow adjustments to these probabilities by state and citizenship status. Generally, the user sets these probabilities to meet the target levels of aggregate participation. (An initial run is performed to count eligible units of various types.) TRIM3 chooses "X%" of eligible units to participate, where &quo;X" is the appropriate probability specified in the program rules. TRIM3 assigns a random number to each unit. Only if that number is lower than "X" does the unit participate.

The participation decision applies to all months in which the unit is eligible for SSI (i.e., a unit either participates in every month for which it is eligible, or not at all). If the unit's benefit level varies over the months, the average monthly level is used for the participation decision.

Calculating the Probability of Participation

An initial probability is obtained from the program rules PartProbFor... based on the unit type and the amount of benefits it is eligible for. Note that the benefit-level categories are specified by the rule FederalBenefitCutoffLevel. This probability is then adjusted based on the unit's state of residence using the rule StateAdjustToProbOfPart and the unit’s citizenship status using the rule CitizenAdjustToProbOfPart.

Calculating the Random Number for Participation

The participation random number is assigned to each unit during the baseline run. Before assigning the random number TRIM3 looks at whether when surveyed any eligible member of the unit reported receiving SSI. These units are called eligible reporters. If the unit contains eligible reporters, the random number is constrained to be below "X", thus causing the unit to participate in the base run. If the unit did not report receiving SSI, a determination is made as to whether that unit is a correct responder (i.e., can we trust its response to the survey question about receiving SSI). This determination is also random, using user-specified probabilities in a manner identical to the determination of the probability of participation -– an initial probability is obtained from the rules CorrProbsFor... and then modified by the rules StateAdjustToProbOfCorrectResp, CitizenAdjustToProbOfCorr and the unit's Medicaid receipt reporter status using the rule MedicaidAdjustToProbOfCorr. (Imputed Medicaid reporters are counted as non-reporters.).

If the unit is determined to be a correct responder the participation random number is constrained to be above "X", thus causing the unit to not participate. For all remaining eligible units (i.e., non-reporters whose responses are not to be trusted) the participation random number is assigned on a purely random basis with no preconceptions about what their participation decision should be. Note that the random numbers established in the baseline are saved and retained for all future SSI runs on a particular year's file.

Purpose of the Participation Random Number

These refinements ensure that all eligible units which report receiving SSI will be simulated to also participate in a baseline simulation, while units for which we believe their negative response will not participate. More important, this method allows units to change their participation decision in runs simulating a change to the baseline. If the change causes a unit to be eligible for higher or lower benefits, it is logical to assume the unit will be correspondingly more or less likely to participate. Since the decision to participate is still done by comparing the unit's random number to a participation probability (which can change by benefit level), a unit that was constrained to either participate or not in a base run could decide differently when facing a different participation probability.

An Example

Assume three different units -- A, B, and C -- all simulated to be eligible for $200/month of federal SSI benefits under current law. Assume also participation probabilities of .5 for units eligible for less than a $180/month, .8 for units eligible for $180-260, and .9 for units eligible for more than $260. If unit A when surveyed reported receiving SSI, it will be assigned a random number between zero and .8. This ensures that it will decide to participate in the current-law run since its random number will never be higher than the participation probability specified for units eligible for $200 (.8). If unit B did not report SSI and TRIM3 chooses it as a "correct responder" its random number will be from the range .8-1. This ensures that it will decide to not participate in the current-law run since its random number will always be higher than the .8 participation probability. If unit C, like unit B, does not report SSI but is not chosen to be a "correct responder," its random number will be anywhere from zero to one. This allows the unit's participation decision to go either way, depending upon the value that is actually assigned as its random number.

If the actual numbers assigned are as follows, their participation decisions in the base run will be:

If the following changes occur to the benefits they are eligible for (and consequently the participation probabilities they face), their decisions will change:

Unit A is now eligible for lower benefits, and the participation probability among $100 units is correspondingly lower than $200 units (.5 vs. .8). Unit A's "taste" or "preference" for participation, as indicated by its random number (.6), while sufficient for choosing participation when eligible for $200, is not sufficient when eligible for only $100. Conversely, unit B is eligible for higher benefits, and is thus more likely to participate (its participation probability goes from .8 to .9). Its "taste" for participation (.85), while insufficient for participation when eligible for $200, is sufficient enough when it's eligible for $300. Unit C, having a generally strong "taste" for participation (.3), continues to participate even though its benefits take the same drop as unit A's.

NonReporterAdjustment Form

The form NonReporterAdjustment provides the user with an additional alignment adjustment to help in those last stages of the alignment when there are a few problem areas that cannot be made better without making something equally important substantially worse. This adjustment helps overcome two limitations of the current participation methodology:

1. Although there is a way to prevent all eligible non-reporters from participating, the ability to make eligible non-reporters participate is constrained by the probability of participation.
2. The probabilities of correct response and their adjustments give only rough and indirect control over what goes on at the individual cell level (e.g., unit type x, benefit level y, state z, and immigrant status t).

This new adjustment takes place in a baseline simulation. It is made as one final adjustment after the participation decision has been made. It only affects eligible non-reporters, and it makes use of information input by the user through this simple form. The form indicates what percentage of particular types of eligible non-reporters should be changed from participants to non-participants, or from non-participants to participants. The form can be changed from year to year as necessary to target different problem areas in each year.

Let's say that we want 5 percent of eligible non-reporters who live in California, who are aged singles, are naturalized citizens, and are not currently participating to be made into participants. In addition, we want 10 percent of eligible non-reporters who live in New York, who are disabled singles, are refugees, and are participating to be made into nonparticipants.

The NonReporterAdjustment form would look something like this:

Enter 0

If FipsStateCode=6 and AnnualUnitType=7 and CorrectedCitizenship=2 then return .05

If FipsStateCode=36 and AnnualUnitType=8 and CorrectedCitizenship=3 then return -.10

Output Variables

The participation random number, after it has been adjusted to account for the unit’s reporter and correct-response status, is stored in the variable RandomNumSSIPartAligned. It is only calculated in a baseline run (i.e. when SimulationMode = 1), and the user should be sure to include it in the list of output variables in the rule AnnualOutput. In an alternative run (i.e. when SimulationMode = 0) this variable must be specified as input through the rule RandomNumSSIParticipation.

The probability of participation (after all adjustments) is stored in the variable ParticipationProbability, and the benefit category the unit was placed in for purposes of determining this probability in stored in BenefitCategory.

If a unit is chosen to participate, the variables MonthlySSIBenefitsRcvd and AnnualSSIBenefitsReceived are set to the same values as the variables MonthlySSIBenefitsEligibleFor and AnnualSSIBenefitsEligibleFor.

Unit-level variables are written to each person in the unit, even if the person is an ineligible member of the unit (i.e. an ineligible spouse). Variable SSIHhldRecipientType stores the household composition as displayed in table A11 (single recipient, married couple recipient, or other recipient household).

Running an Alternative Simulation

To run an alternative (as opposed to baseline) SSI simulation, do the following:

• Set the program rule SimulationMode to 0 (Non-Base).
• The variable list program rule PotentialChildInBase should specify the variable PotentialDisabledChildType from the base SSI run.
• The variable list program rule RandomNumSSIParticipation should specify the variable RandomNumSSIPartAligned from the base SSI run.
• The variable ParticipationOption should be set based on the analyst’s goal. Choices are:
  • 0 - Determine participation probabilistically
  • 1 - Eligible units make same decision as baseline
• The variable list program rule BaselineEligibility should specify the variable "AnnualSSIBenefitsEligibleFor"; and
• The variable list program rule BaselineParticipation should specify the variable "AnnualSSIBenefitsReceived".

For more information see the section Baseline vs. Alternative Simulations in the special section on Processing Children Under 15

Processing Children Under 15

Children may be eligible for SSI if they are disabled. As described earlier, TRIM3 determines if a person is disabled using labor force activity questions, reported receipt of disability income, and (when available) activity limitation indicators. However, since the CPS does not include income and/or labor force activity data for children under 15, an alternative method must be used to determine if children under 15 are disabled. Our alternative methodology allows us to assign SSI receipt to a population of children whose key characteristics mirror those of the children who actually receive the benefit. Our methodology is not able to estimate the number of children eligible for SSI due to the limitations of the CPS variables and the complexity of determining children's disability.

As mentioned above, children who are identified as disabled under the expanded reporter definition are excluded from this process.

Initial Selection of Potential Disabled Children

If a family includes children under 15, TRIM selects one or more of those children as a "potential" disabled child. In this selection process, related subfamilies are treated as separate families. If more than one child is reported to be an SSI recipient in the survey data, all of the children reported as SSI recipients are treated as reporters.

PotentialChildSelectionMethod specifies the method to be used for selecting which (if any) children below age 15 will be considered as potentially disabled. Any of the selected children who subsequently pass all SSI eligibility tests (i.e. asset and income tests) are subject to a random selection process to determine who will be simulated to receive SSI.

To select potentially disabled children, families with children under 15 are divided into two groups:

• Categorically Ineligible Reporters - The head or his/her spouse reports receiving SSI but the recipient does not meet TRIM's definition of aged or disabled. In these families, the SSI reported by a parent may actually be the SSI of a child.
• Non-reporters or Categorically Eligible Reporters - Neither the head nor spouse report receipt of SSI, or the recipient meets TRIM's definition of aged or disabled.

When processing a "Categorically Ineligible Reporter" family, TRIM selects children with any of the activity limitations specified in DisabilityIndicators2 as potentially disabledren. If no activity limitation variables are specified in DisabilityIndicators2, TRIM checks if any of the children under 15 report receiving Medicaid. Using Medicaid as an indicator of disability improves the characteristics of the simulated SSI children's caseload relative to those of the actual caseload. If so, the oldest such child is selected as a potential disabled child. Otherwise, the oldest child under 15 is selected. Regardless of the selection method, a child selected from this type of family is referred to as a "Type 1" child.

When processing a "Non-reporter" or "Categorically Eligible Reporter" family, TRIM selects children with any of the activity limitations specified in DisabilityIndicators2 as potentially disabled. If no activity limitation variables are specified in DisabilityIndicators2, TRIM selects the oldest child under 15 as a potentially disabled child. ProbMultChildDisab is used to indicate the probability that there is a second non-reporting child in the family without activity limitations who is potentially disabled. In non-reporting families with more than one child, a second child is selected as potentially disabled if the child’s random number is less than or equal to the probability in ProbMultChildDisab. Regardless of the selection method, children from non-reporting families are referred to as "Type 2" children.

Selecting Potential Disabled Children

For both types of potential disabled children, TRIM determines financial eligibility and benefits, just as it does for children 15 and older. For each potential disabled child who is found eligible for a positive benefit in at least one month during the year, a random number is compared to a probability to determine if the child will move from "potential" to "participant" status. Children who are selected as participants are simulated to receive the benefits in all the months in which they were eligible.

The user can specify the portion of Type 1 children to be selected through the program rule PotentialChildType1Prob. The program rules PotentialChildType2Prob0Parent, PotentialChildType2Prob1Parent, PotentialChildType2Prob2Parent, PotentialChildType2AgeAdj, PotentialChildType2StateAdj, and PotentialChildType2MedicaidAdj allow the user to specify the portion of type 2 children to be selected. During each year's baseline alignment process, these probabilities are set such that TRIM3's resulting caseload of SSI children comes acceptably close to the actual SSI children's caseload, both in number and in key characteristics.

Program rule PotentialChildType2HhldPartAdj may be used to adjust the probability that a Type 2 child will be selected based on receipt of SSI by adults in the household whose eligibility and participation decisions have been determined. A value ranging from 0 to 10 may be entered. The first array value adjusts the probability of selection when no adult in the household receives SSI, and the second array value adjusts the probability of selection when one or more adults in the household receive SSI. The values entered into PotentialChildType2HhldPartAdj are multiplied by a child’s randomly selected probability of being selected to either increase or decrease the probability. Program rule MultChildType2PartOption applies only to children identified as "Type 2" potential recipients when there are more than one Type 2 child in a family. The option controls how a value is selected for the participation adjustment factor PotentialChildType2AgeAdj and whether the random number to which the final probability is compared differs across the children.

Output Variables

For purposes of setting micro-level output variables, potential disabled children who do not move from "potential" to "participant" status (for whatever reason), are treated as categorically ineligible persons -- none of their output variables will indicate that they were ever considered as potential disabled children. Potential disabled children who do move from "potential" to "participant", in addition to having correct values for the standard SSI output variables, will have a value of "1" or "2" for the variable PotentialDisabledChildType to indicate their type. Thus, the only children under age 15 who are coded as being eligible for SSI are those who are selected as program participants -– there are no children under 15 who will be coded as eligible non-participants.

Baseline vs. Alternative Simulations

Although the actual selection probabilities to be used for each type of child are up to the user, type 1 children are generally assigned higher probabilities than type 2 children since the presence of unexplained SSI income makes it more likely that there really is a disabled child in the family. This assumption is reasonable as long as the rules TRIM3 is using for determining categorical eligibility match the rules that were actually in effect during the period covered by the CPS. However, if TRIM is being used to simulate an alternative set of rules -- for example raising the minimum eligible age from 65 to 70 -- more persons will show up as categorically ineligible reporters, yet their reported SSI income should not be considered "unexplained".

To avoid having a different pool of categorically ineligible reporters in an alternative simulation (one with SimulationMode set to 0), alternative simulations rely on the previously-run baseline simulation to identify "type 1" and "type 2" children. (The program rule PotentialChildTypeInBase specifies the variable with this information.) Those children and only those children are checked for financial eligibility and for benefit level according to the rules of that simulation. Some of those children may become ineligible or may be eligible for higher or lower benefits based on the new rules. But the number of disabled children receiving SSI cannot increase from a baseline to an alternative simulation under the current methodology.

Reporter Status

For various purposes, the SSI simulation needs to know whether a person or a unit should be considered a "reporter" -- i.e. did they report receipt of SSI on the CPS. This determination is made as follows.

Selecting Persons as Reporters

The program rule ReporterOption indicates which definition of SSI reporter will be used. Any persons who subsequently pass all SSI eligibility tests will be considered eligible reporters in the SSI baseline simulations. Those not passing all eligibility tests will be considered aged or disabled for purposes of other models. (See sections on categorical eligiblity for adults and children for more details.)

Regardless of definition, if AllocFlag665 indicates the entire supplement was allocated, then no one in the unit is considered a reporter.

The basic reporter definition considers any person where the input variables AllocFlagSsiReceipt not = 1 and Ssi > 0 a reporter.

The expanded reporter definition considers a person a reporter if:

1. They are a child receiving SSI as given in the rule ChildReceivedSSI where the value is not imputed.
2. They are a parent reporting SSI on behalf of themselves and a child (ReasonForSSI = 1, 2 or 5), where the reason is not imputed.
3. They are reporters under the basic definition, with the exception that parents who give ReasonForSSI = 3 or 4 (on behalf of a child), where the reason is not imputed, are not considered reporters.

Persons who are selected to be reporters will have the annual result variable ReporterStatus equal to 1.

To replicate results prior to version 14 of the code, set ReporterOption to "basic reporter definition."

Selecting Reporter Units

For the purposes of classifying units as reporter units in the alignment tables, and for determining if a person should be considered a pre-reform SSI recipient, if any person in the unit is a reporter, the unit is considered a reporter unit. This is true even if the reporter is a categorically ineligible member of the unit. The result of this determination is stored in the monthly output variable IsUnitReporter for every person in the unit, even if they are categorically ineligible. Even though this is a monthly variable, TRIM does not allow the SSI reporter status to vary from month to month (i.e. a person or unit is considered a reporter for every month, or for no months).

For the purposes of the participation decision, the determination as to whether a unit reports or not is based on the reporter status of categorically eligible members only.