To understand the variation in results, a 2007 meta-analysis, The Impact of Railway Stations on Residential and Commercial Property Value, synthesized U.S. and international studies.

The papers examined many different systems types, from bus rapid transit to heavy rail, and all types of property, including vacant lots, homes, businesses, and industrial sites. Based on the available literature, the meta-study concluded:

• Because of their larger service area, commuter rail stations have a greater impact on property values than light rail or subway stations.
• Commercial properties within a quarter mile of a station sell or rent for 12.2% more than residential properties in the same distance range.
• For every 250 meters closer to a railway station, the property value effect is 2.3% higher for residential properties than commercial properties.
• When transit modes other than trains are available in an area, railway stations generally have a lower impact on property value.

A 2009 University of Texas metastudy, Bus Versus Rail: Meta-Analysis of Cost Characteristics, Carrying Capacities, and Land Use Impacts, looks at the cost, operational characteristics, and land-use impacts of different mass-transit technologies.

The study’s main purpose, as the author writes, is to “provide a balanced view that will help identify conditions under which a particular transit mode, bus or rail, is most appropriate.” Factors such as transit supply and demand, availability of public resources and potential land use impacts of the system are considered.

The study’s cost conclusions include:

• On average, bus rapid transit (BRT) costs $10.24 million in 1990 dollars per mile to build. This figure is less than half that of that for light rail transit (LRT), $26.4 million and one-tenth of metro rail transit (MRT), $128.2 million. However, in some situations BRT can be more expensive per mile than LRT, and some LRT systems have exceeded the per-mile cost of MRT projects.
• Compared with LRT systems, bus rapid transit is associated with greater land-acquisition costs ($3.018 million per mile, versus $1.52 million). In addition, dedicated BRT guideways average $6.459 million per mile versus $4.289 million for light rail. Station costs are also slightly higher for BRT than LRT.
• Bus systems have the lowest cost per vehicle revenue mile and revenue hour, $3.1  and $45, respectively, but the highest cost per thousand passenger mile, $616.4.
• BRT systems cost per vehicle revenue mile were almost as low as bus systems’, $3.6, and the cost per thousand passenger mile was 24% lower, $496.9.
• Light rail systems have the highest cost per vehicle revenue mile, $9.3, and the second highest cost per passenger mile, $578.
• Metro systems cost less than LRT systems per vehicle revue mile, $6.5; the most per vehicle revenue hour, $152; and the least per thousand place mile and thousand passenger mile, $49.2 and $282, respectively.
• Buses have the lowest average line capacity per hour, 3,800 to 7,200. BRT can carry 9,000 to 30,000 per hour and LRT can carry 12,200 to 26,900. The highest potential line capacity is of MRT, 67,200 to 72,000.

In concluding, the author concludes that, on average, “BRT can outperform LRT in providing a moderate to high level of service capacity at a moderate level of capital and operating costs in neighborhoods with moderate population and job densities.” While MRT are the most expensive to build, they can achieve over five times the capacity of BRT or LRT, and are associated with the largest positive impact on property values in the vicinity of stations.

The author cautions that there is no one answer, however. “Each transit technology is efficient when it is in the right place serving the right market.”

To help consumers, businesses, and organizations make optimal choices, Congress asked the National Resource Council to assess the cost of energy production and use. The results are available in Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use.

The committee that that wrote the report concentrate on air pollution created by energy production and use, including sulfur dioxide, nitrogen oxides, and particulate matter, on human health, crops, buildings, and recreation. When possible, it estimated was the damages in 2005 and what the damages would be in 2030 if current policies continue.

• Coal, which accounts for half the electricity produced in the United States, caused about $62 billion in nonclimate external damages, the equivalent of 3.2 cents per kilowatt hour. Coal emits an average of one ton of CO2 per megawatt-hour of electricity produced. Climate-related damages range from 0.1 to 10 cents per kilowatt hour.
• Burning natural gas to generate electricity caused $740 million in nonclimate damages in 2005, the equivalent of 0.16 cents per kilowatt hour. Climate damages from natural gas are half that of coal, ranging from 0.05 to 5 cents per kilowatt hour.
• Heating accounts for 30% of U.S. natural gas use, and caused $1.45 billion in damages, about 11 cents per thousand cubic feet.
• Transportation accounts for 30% of U.S. energy demand, and in 2005 produced $56 billion in nonclimate damages.
• Damage per vehicle mile ranged from 1.2 to 1.7 cents.
• Corn-grain ethanol caused more damage than gasoline, while ethanol made from herbaceous plants had lower damages.
• Damages caused by electric and hybrid vehicles was higher than those created by conventional vehicles in 2005 and will continue to be so in 2030. While the vehicles create few emissions, the electricity to power them relies heavily on fossil fuels. In addition, the energy used in creating the batteries and electric motor increase life-cycle damages by 20%.

Coal currently provides more than half the United States’ electricity, and we have 261 billion tons of reserves, 27% of the world’s total. Yet burning a single ton of coal can create more than two tons of CO₂, a primary contributor to climate change. To reduce CO₂ emissions, a technique known as  carbon capture and storage (CCS) is under development.

Three factors will determine the future of CCS: scale, security, and cost. Immense amounts of CO₂ would need to be stored permanently, and if CCS makes coal-generated electricity more expensive than that of other technologies, incentive to adopt it would be reduced.

A 2009 Harvard study, Realistic Costs of Carbon Capture, concludes that:

• For a first-generation facility, the cost of abatement would be $100-150 per ton of CO₂ avoided, excluding the cost of transportation and storage.
• Carbon capture and storage would add approximately 8-12 cents per kilowatt hour to the cost of coal-generated electricity, effectively doubling its cost.
• When carbon-capture technology is mature, costs could decline to $30-50 per ton of CO₂ avoided, adding 2-5 cents per kilowatt hour to the cost of coal-generated electricity.

The cost premium for generating low-carbon electricity from coal with CCS would be similar to that for generating low-carbon electricity by other means, and higher than certain renewables such as onshore wind.

A good starting point to understand the complexities of the charter-school issue is a 2009 RAND Corporation study, Charter Schools in Eight States: Effects on Achievement, Attainment, Integration, and Competition, which is based on data from more than 600 charter schools.

The RAND Corporation study found that:

• Reading and math performance showed insignificant changes in five jurisdictions and small decreases in two.
• Charter high schools’ rates of graduation and college matriculation improved in the two jurisdictions with data.
• There was no evidence that average public-school student achievement increased or decreased in response to establishment of charter schools; that charter schools skimmed high-achieving students from public schools; or that charter schools led to increased racial or ethnic stratification.

Cap and trade is a market approach for reducing greenhouse gas emissions. The government sets a mandatory cap for a particular pollutant and then allows companies to negotiate among themselves on how to meet the limit; those that are most efficient at reducing their emissions are rewarded for doing so.

A reliable resource on cap and trade is an Environmental Defense Fund study, What Will It Cost to Protect Ourselves from Global Warming? The Impacts on the U.S. Economy of a Cap-and-Trade Policy for Greenhouse Gas Emissions.

Key findings of the analysis include:

• The overall cost of capping greenhouse gases for the average American family will amount to less than 1% of household budgets over the next two decades.
• The total number of jobs affected by climate policy in the manufacturing sector over 20 years is substantially below the number of jobs created and destroyed in the sector every three months.
• Household electricity and natural-gas bills rise by only a few dollars a month over the next few decades well within the rise and fall homeowners already experience.

Scientists from UC Santa Barbara and the University of Hawaii suggests a possible solution, “Can Catch Shares Prevent Fisheries Collapse?” to the problem of overfishing. In their study, the authors looked at statistics from more than 10,000 fisheries between 1950 and 2003. They found that catch-share systems, which encourage fishermen to act cooperatively rather than competitively, can reduce and possibly even reverse fisheries collapse.

Key findings include:

• As of 2003, fisheries using a catch-share system were collapsed about half as often as fisheries not using the system.
• Assigning secure rights to fishermen leads to significantly improved catches as well as financial returns.
• Catch-share systems not only slow the decline toward widespread collapse, but actually stop this decline.

The authors conclude the study by writing: “These findings suggest that as catch shares are increasingly implemented globally, fish stocks, and the profits from harvesting them, have the potential to recover substantially.”

A useful place to learn more about the range of issues concerning ethanol is “Ethanol: Law, Economics, and Politics,” a cost-benefit analysis by the Brookings Institution.

It and other studies provide considerable insight, including:

• If all U.S. corn production were transformed into ethanol, it would replace only a fraction of our petroleum consumption. Estimates range from 3.5% to 12%.
• While ethanol is often portrayed as a path to energy security, corn yields can be highly volatile.
• Improvements in yields peaked in the early 1960s and has since been decreasing. The current rate of increase is not sufficient to keep up with growing food demand.
• The U.S. produces 60% of world corn exports. Diverting this to ethanol production would have significant international consequences, yet do little to increase our energy security.

Researchers used data from NASA and built their analysis on conservative assumptions. They conclude that:

• Wind could supply more than 40 times current worldwide consumption of electricity, and more than five times total global use of energy in all forms.
• In the contiguous United States, wind has the potential to supply as much as 16 times total current domestic electrical demand.
• When required, new power transmission lines add appropriately 10 percent to a project’s cost, and consequently are not prohibitive.
• Wind-energy potential falls below demand only during the summer months, when winds decrease and electrical use rises.

A 2009 study by the Institute of Medicine, Secondhand Smoke Exposure and Cardiovascular Effects, has determined that the health benefits of smoking bans are both immediate and significant. Sponsored by the Centers for Disease Control and Prevention, the report looked at 11 U.S. and European studies on the health effects of smoking bans.

Based on the studies examined, the researchers concluded:

• All studies showed a significant reduction in heart attacks after bans were introduced, from 6% to 47%.
• Heart-attack rates begin to fall quickly after bans are introduced.
• Exposure to secondhand smoke significantly increased the chance of both smokers and nonsmokers having a heart attack.
• Secondhand-smoke exposure increased the risk of coronary heart disease by 25% to 30%.

The researchers’ findings confirm those of an earlier report from researchers at the University of California, Berkeley. It determined that heart-attack rates drop 17% after smoking bans are instituted.