In-kind Aid is more efficient, but only by a small amount. The Census compared the number of people raised out of poverty by excluding individual programs, then dividing those numbers by the cost of individual programs gets you the average cost / person raised out of poverty. The average efficiency of In-kind Aid is ($17,000-19,300)/person. The average efficiency of Cash Aid is ($20,000-$21,500)/person.
This is a difficult question for multiple reasons. Poverty has different measures. Absolute Poverty that is used in developing countries and is usually defined is living on less than $X per day ($1.25 is considered extreme, and $2 is considered moderate). Relative Poverty is used in OECD and European Union nations, and is defined as a level of income below some percentage of the median income (60% usually). These definitions lead to your second problem, how do you define in-kind transfers and cash aid transfers?
If you don't measure in-kind transfers based upon their dollar value worth (i.e. the goods have $0 value), then you cannot increase the $X per day that someone is living on nor increase their income. Cash aid transfers on the other hand might be considered gifts if they came from a private individual or as in many instances aren't included as income in official poverty estimates. (i.e. the Earned Income Tax Credit (EITC) and Child Tax Credit in 2011 could result in a $5,751/$3000 respective tax grant for a family with 3 children)
Luckily, the Census Bureau adopted a Supplemental Poverty Measure (SPM) based on research by the National Academy of Sciences to address these weaknesses, the new poverty measure changed the definition of both the thresholds and family resources (pg. 2, pg. 3 table showing differences between Official and Supplemental poverty measures).
The SPM thresholds should represent a dollar amount spent on a basic set of goods that includes food, clothing, shelter, and utilities (FCSU) [...] reflect the needs of different family types and geographic differences in housing costs [...] at the 33rd precentile of the expenditure distribution.
SPM family resources should be defined as the value of cash income from all sources, plus the value of in-kind benefits that are available to buy the basic bundle of goods (FCSU) minus necessary expenses [...] In-kind benefits included nutrition assistances, subsidized housing, and home energy assistance. Necessary expenses that must be subtracted include income taxes, Social Security payroll taxes, childcare and other work related expenses, child support payments to another household, and contributions toward the cost of medical card and health insurance premiums, or medical out-of-pocket costs (MOOP).
Under the SPM definition, there were 49.7 million poor in 2011 (46.6 Official definition), or 16.1% (+/- 0.3%) of the population. Table 5a. (pg. 15) breaks down the effect on the SPM rate by excluding individual elements from the SPM. I have included the calculations for millions of persons in poverty when excluding individual elements (Column 3), the difference from the SPM (Column 4), the cost in millions of $US (Column 5), and the cost per person (Column 6).
Supplemental Poverty | All Poor Persons | Cost |Cost/ |
Measure | 90% C.I. Millions | | Person| Source
Elements |(+/- 0.3%) Diff. |($mil) | |
-----------------------+-------+------+------+--------+-------+--------
Research SPM | 16.1% | 49.7 | | |
Social Security | 24.4% | 75.3 | 25.6 |$724,923|$28,317| OMB-Mandatory Prog
-Social Security(OASI)| 24.4% | 75.3 | 25.6 |$612,400|$23,921| Census
-Social Security(OASI)| 24.4% | 75.3 | 25.6 |$595,619|$23,266| OMB-Outlays Indiv.
Refundable tax credits | 18.9% | 58.3 | 8.6 | $80,828| $9,399| IRS
SNAP | 17.6% | 54.3 | 4.6 | $82,885|$18,018| USDA
Unemployment Insurance | 17.2% | 53.1 | 3.4 |$117,226|$34,478| OMB-Mandatory Prog
-UI(Census) | 17.2% | 53.1 | 3.4 |$132,700|$39,029| Census
-UI(OMB) | 17.2% | 53.1 | 3.4 |$118,607|$34,884| OMB-Outlays Indiv.
SSI | 17.2% | 53.1 | 3.4 | $55,885|$16,436| SSA
-SSI(Census) | 17.2% | 53.1 | 3.4 | $49,300|$14,500| Census
-SSI(OMB) | 17.2% | 53.1 | 3.4 | $49,562|$14,577| OMB-Outlays Indiv.
Housing Subsidies | 17.0% | 52.5 | 2.8 | $26,728| $9,545| HUD
-Housing Sub(Census) | 17.0% | 52.5 | 2.8 | $59,200|$21,142| Census
-Housing Sub(OMB) | 17.0% | 52.5 | 2.8 | $45,869|$16,381| OMB-Outlays Indiv.
Child Support received*| 16.5% | 50.9 | 1.2 | $4,159| $3,466| HHS
-Child Support(prelim)| 16.5% | 50.9 | 1.2 | $5,700| $4,750-$30,750 | HHS-Pre
School Lunch | 16.4% | 50.6 | 0.9 | $17,324|$19,249| USDA
TANF/General Assistance| 16.4% | 50.6 | 0.9 | $17,285|$19,205| HHS
WIC | 16.2% | 50.0 | 0.3 | $6,734|$22,447| USDA
LIHEAP | 16.2% | 50.0 | 0.3 | $4,701|$15,670| HHS
Workers compensation | 16.2% | 50.0 | 0.3 |
Child support paid | 16.0% | 49.4 | -0.3 |
Federal income tax | 15.6% | 48.2 | -1.5 |
FICA | 14.8% | 45.7 | -4.0 |
Work expense | 14.4% | 44.6 | -5.1 |
MOOP | 12.7% | 39.2 |-10.5 |
-----------------------+-------+------+------+
Sources:
-Social Security: Social Security OMB-Table8.4-Outlays for Mandatory and Related Programs(AZ28)
-Social Security, Unemployment, Supplemental Security Income, Housing Assistance: Social Security Census-Table474-Outlays for Payments for Individuals ...(pg. 1)
-Social Security, Unemployment, Supplemental Security Income, Housing Assistance: Social Security OMB-Table11.3-Outlays for Payments for Individuals ...(pg. 252)
-Refundable Tax credits: IRS-Table3.7-All Returns: Tax Liability, Tax, Credits ...(CX10 + CZ10)
-SNAP/Food Stamps: USDA-Budget Summary and Annual Performance Plan(pg. 61 pdf)
-Unemployment Insurance: OMB-Table8.4-Outlays for Mandatory and Related Programs(AZ18)
-Supplemental Security Income: SSA-Supplemental Security Income Program-Table2.3 (pg. 6)
-Housing Assistance: HUD-Budget Authority by Program (Total, TBRA. pg. 75 & Subtotal, Housing Program 78)
-Child Support (enforcement): HHS-Adminstration for Children and Families(pg. 97)
-Child Support (collected): HHS-Office of Child Support Enforcement FY2011 Preliminary
-School Lunch: USDA-Budget Summary and Annual Performance Plan(pg. 61 pdf)
-TANF/General Assistance: HHS-Adminstration for Children and Families(pg. 97)
-WIC: USDA-Budget Summary and Annual Performance Plan(pg. 61 pdf)
-LIHEAP: HHS-Adminstration for Children and Families(pg. 93)
Notes regarding calculations: The Cost ($mil) for "Child Support received" is the cost to the government to enforce Child Support payments. As noted in the HHS-FY2011 preliminary report, the cost of child support enforcement was $5.7 billion (Chart 4), which collected $31.2 billion (Chart 2) in child support. The enforcement costs differ between the HHS-Budget in Brief and the preliminary report, so both calculations are presented. It also might be unfair to not include the "cost" to the person whose wages are garnished, so I have included that as well. Several elements have multiple Cost ($mil) (indicated by an indented dash '-'). This was due to large discrepancies between the Office of Management and Budget, the Census, and the reporting agency. Workers' Compensation was not included in the analysis. Although coverage is mandated in most states, I had difficulty finding good data (except for federal employees, this function is privatized) and didn't feel that this was a targeted anti-poverty program.
Cash Aid - Social Security, Refundable tax credits, Unemployment Insurance, Supplemental Security Income (SSI), Child Support received, TANF/General Assistance
The most efficient of these programs is Refundable tax credits. At a cost of $81 billion in FY2011, they were able to help out 8.6 million people out of poverty, at a cost of about $9,399/person. The least efficient is the Unemployment Insurance, with a $117 billion FY2011 budget, they helped 3.4 million people, at a cost of about ($34,000-$39,000)/person. The average efficiency of Cash Aid is ($20,000-$21,500)/person depending upon using Census/OMB/agency figures. If you include child support enforcement costs only, this becomes about $18,000 (+/- $500), and $22,500 (+/- $500) if you include the child support recovered dollars.
In-kind Aid - SNAP, Housing Subsidies, Women, Infants and Children Program (WIC), Low Income Home Energy Assistance Program (LIHEAP), School Lunch
The most efficient of these programs is Housing Subsidies. With an $27 billion budget in FY2011, they were able to help out 2.8 million people out of poverty, at a cost of about $9,500/person (Note: If you use the Census or OMB measures, LIHEAP is more efficient at about $15,500/person). The least efficient is the Women, Infant and Children Program (WIC), with a $6.7 billion FY2011 budget, they helped 300,000 people, at a cost of about $22,000/person. The average efficiency of In-kind Aid is ($17,000-19,300)/person.
Conclusion
These figures indicate that In-Kind aid is slightly more efficient than Cash Aid when implemented by the government.