Saturday, November 21, 2015

What is Wrong with Referendums? A Reply to Geert Wilders

Recently (2015-11-19) Geert Wilders published an article in New York Times arguing that Europe should hold national referendums on immigration policy. But referendums are not necessarily fair, nor are they the ultimate form of democracy. Referendums have two problems: first, only insiders can vote, even on questions that largely concerns outsiders. Second, everyone has a single vote of equal weight, even in case where the importance of the outcome differs widely.

Who Can Vote?

Current "universal" voting is limited to "insiders", those who are either confined to a certain territory, or possess a certain legal status. In case of national referendums, these are typically citizens of the country; in local referendums these may be residents of a city. Outsiders cannot participate, even when voting over issues that have major consequences for them. This violates a central pillar of democracy, the ability to influence decisions that affect you.

A referendum over immigration policies is just such an example. Unless potential immigrants also participate, we cannot talk about universal democratic decision. Similar issues arise when neighborhood residents vote for restrictive zoning laws. The potential "immigrants" to the neighborhood who are adversely affected cannot participate because they are not residents. The Greek referendum of 2015 shared similar traits: only Greek citizens were voting over a decision that involved most of the EU.

Greek 2015 referendum ballot
Greek 2015 referendum ballot. The referendum had several problems, only Greek citizens voting over a pan-European decision was perhaps it's most serious flaw.

How Big Is the Vote?

Another problem with referendums is the "size" of vote. Traditionally, everyone has a single vote. This is true even if different people have very different stakes in the question. In this way the majority can always outvote a minority. For instance, in many places the majority may outlaw homosexuality. The Swiss minaret law is an outcome of a referendum that was flawed in this way. I don't know how many Muslims and non-Muslims actually care about minarets, but I can imagine it is a far less important issue for non-Muslims. But they could easily muster a majority. As an extreme example, imagine that Hitler put Nuremberg Laws, the Nazi laws that robbed Jews of their rights, on a national referendum. Would we consider the outcome democratic? Analogously, potential migrants may outvote the whole EU if given an equal weight.


Unfortunately, these two problems cannot easily be corrected. Although it is not fair to exclude outsiders from decision–making, and give equal say for those with unequal stakes, we cannot calculate the fair vote size. Referendum is justified when the electorate has roughly equal stakes and outsiders are little affected. If this is not the case, one should not call for a referendum.

Instead, we may strive toward inclusive representative bodies that also involve outsiders. In case of the current refugee crisis it should include representatives from both EU, and refugee origin and transition countries. Such conferences, potentially meeting regularly, would ensure that insiders have more rights but outsiders will also have a say.

Wednesday, November 18, 2015

Britain in EU: More Powers to National Parliaments?

EU: More Power to National Parliaments Is not Always Democracy

More power to national parliaments is a democracy–enhancing move only if the national decision-making occurs in areas that have little impact on the others. If the opposite is true, it diminishes the control we have over the important decisions.


David Cameroon has announced his requests to the EU. One of them is a larger role for national parliaments in shaping EU regulations. Although national parliaments may be the most democratic institutions we have, the areas where such a "repatriation of powers" occurs must be chosen carefully. Otherwise it may weaken the democracy instead. There are two main reasons.

David Cameroon and EU
Just a common market—or an "ever closer union"?


First, and most importantly, only some decisions can be made by national parliaments. Many decisions can not, such as international treaties, trade agreements and international law. Almost by definition this type of legislation is not made by individual states. Analogously, parliaments do not vote on what the other countries do, be it introduction of incompatible regulations, or conducting irresponsible fiscal policy in the hope that we will bail them out later. Neither have we much room to vote about technical standards, such as Apple's new operating system or airport security procedures.

A number of major problems EU currently faces cannot be solved at national level. For instance, the refugee inflow must either be received, or stopped, at the EU border. The current country-based decision making essentially allows Hungarian parliament to decide over number of refugees in Serbia and Croatia, and, if German "national parliament" decides to close it's borders, it has severe impact on Greece and Italy. Analogously, the "single market", one of the pillars of EU, is a form of extended free-trade agreement, a large number of common standards for product labeling, food safety, and labor treatment. By definition, agreement is something we cannot do alone.

More powerful national parliaments in this type of decisions will weaken EU without strengthening the member–states. We will notice more small inconveniences, such that you cannot use certain mobile services in another EU country, or your business has to hassle with incompatible regulations across the border. Negotiations among 28 sovereign states are far more slow and costly than central decisionmaking, and there is little incentive to overcome even small special interests in the name of a common good. National politicians are elected to stand for "national interests", and all 28 national interests are seldom aligned with the common one. The underlying problem is interdependency, our decisions may influence others even if the others do not belong to our "nation". Such decisions should be done by inclusive higher level bodies, such as European Parliament.

Enfranchisement of EU Migrants

The other, and currently less important reason, is enfranchisement of EU migrants. This is a large group of people who cannot vote in national elections but is subject to the corresponding national legislation. This is simply not fair. I think the first-best solution would be to give EU migrants voting rights rather soon after moving to another country (say, in 2 years). But until it happens, decision–making by EU institutions offers this group more say about their lives.


Finally, even EU is too small for many important decisions. Many contemporary problems, such as global trade agreements, climate change, or the puzzle of Middle–East, cannot be solved at EU level either. We need global governance more than ever before. How to achieve this in a democratic way is one of the big challenges of our time.

Saturday, October 31, 2015

Improving the Pedestrian Experience: The Cheap Way

Improving the Pedestrian Experience: The Cheap Way

Traffic improvements may sometimes be cheap. Below I show how to enhance the walkways around a University of Washington (UW) building, Schmitz hall, in Seattle at University Way and 41th street.

A bit of background. University Way is a lively shopping street one block west of the UW campus. It is a major pedestrian destination and also an important connection street. UW campus begins one block east of it, on the other side of 15th avenue. At the end of Campus Parkway (40th street) there is a much used walkbridge over 15th. Schmitz hall is located just between the walkbridge and University Way and hence a major walking corridor embraces it from both sides.

Let's start from north, approaching the campus from University Way (see the picture). We don't want to follow the sidewalk straight down (south)—then we have to climb up later again to reach the walkbridge. We take instead the level walkway around the hall, either by turning left, or south. However, as you can see, the most direct route to the walkway is blocked by a small decorative wall. This is the first cheap improvement: just remove the wall.

A decorative wall blocking the direct route
NW corner of Schmitz Hall at University Way (right) and 41th street. The walkbridge is at the SE corner of the building, behind it at left.

Compared to typical Seattle sidewalks, the walkway is surprisingly spacious. Unfortunately, a half of it is blocked by short stairs, leading to the sidewalk at about 1m above it (see the picture below). This makes a large swath of the walkway unsuitable as a connector route. I don't know if it is used for anything else. Note that even the narrow gap between stairs and a concrete pillar is blocked by a trashcan.

Otherwise wide walkway rendered narrow by stairs
The walkway on the north side of Schmitz Hall. The wider left-hand side is mostly blocked by stairs (middle-left on the picture).

But the next picture indicates just how easy it is to recover almost half of its walkable width: a) move the bin; and b) remove the lower part of the concrete wall that lines the stairs. Metal handrails are enough for safety. You may even shorten the handrails a bit at the lower end. This is easy and cheap.

Bad placement of trashcan
A trashcan is placed in the narrow passage between stairs and a concrete pillar.

The next obstacle is a bike rack. Well, not the rack itself but the bikes that extend far out of the rack. Fortunately the solution is easy: turn the rack 90 degrees and move it over to the left side.

Bad location for bike rack
The bike rack is placed gently between the columns. Unfortunately, the bikes occupy most of the walkway.

After passing the rack we reach the bridge with no further obstacles. However, there is another issue that can easily be solved. A bus stop is located at the 15th avenue, just at the end of the footbridge. Unfortunately, as the street is about 1m lower than the walkway at the end of the footbridge, one has to walk around the waiting shelter ("out of the picture" on right-hand side). This adds about 15 seconds to the walking time compared to the direct route.

Bus stop with no direct access
Those arriving from campus over the walkbridge (visible in the background) must walk around the shelter to get to the bus. One should construct stairs at the direct line between the bridge and where the bus stops—in the center of the picture. The bus stands on 15th avenue, a wall of Schmitz Hall is visible in the upper right corner.
15 seconds feels rather long when the bus is just coming, and as a handy shortcut, many jump the wall instead. Indeed, this is a place where one can easily add small stairs.
Direct route to the bus stop includes jumping this wall
Landscaping beneath the wall indicates that many passengers do not take the trip around the shed but just jump.


We need more attention to small details when desiging transportation infrastructure. The examples above indicate that improvement can sometimes be achieved with very little costs, or even at no cost if such considerations are taken into account in the original design. We need more awareness and understanding of pedestrian mobility at least as much as money. In this case it is about directness and space: we don't want to go around if a direct route is just here, and we don't like narrow passages.


AD ENDUM: I moved the bike rack out of way.

Bike rack out of way
Bike rack moved out of way

Tuesday, July 28, 2015

Gas Tax May Be a Simple and Good Enough Road Usage Charge

Gas Tax May Be a Simple and Good Enough Road Usage Charge

US road maintenance is underfunded. Unfortunately, current politics does not offer any sustainable funding ideas either. Instead, we hear about various one time patches like playing with custom tariffs or selling strategic oil reserves.

A good funding mechanism is based on the following principles:

  1. It creates a steady income.
  2. The Income grows and falls according to the road maintenance needs. This means it is related to the total driving mileage.
  3. The funding burden is closely associated with individual road usage, in particular the damage one causes to the road structures when driving.
  4. The mechanism is largely inflation-proof and does not require frequent political interference.

I-110 in Los Angeles
Freeways permit fast uninterrupted travel through dense urban environments. But they are not cheap. I-110 in LA.
By Adrian104 [Public domain], via Wikimedia Commons

In recent years we have seen an increased interest for "road usage charge", a user fee that depends on the actual driving mileage. Indeed, modern technology (currently tested in Oregon) allows to determine the exact mileage on different types of roads, and to send the driver the bill afterwards. Here I argue that we do not have to wait for the a technology to mature, as old-fashioned gas tax may serve as a good substitute for a smarter driving distance fee. I solely focus on road maintenance funding, and ignore congestion, pollution, and climate issues. Note that from this perspective there is no difference between fossil fuel, biofuel, and electric cars.


Two arguments strongly favor gas tax over alternative funding mechanisms: it's simplicity and it's focus on road users. The main objections are related to it's impact on economy, and the fact that it is less than perfect measure of actual road usage.

  • Gas tax is simple to introduce, collect and pay. First, the direct payments are done by big oil market operators who can easily handle a rather minor additional administrative burden. Second, most governments already collect it, hence the additional administrative burden would be even smaller. Third, such "pay-at-pump" scheme is the simplest imaginable tax for motorists. You pay for your gas and that's it.

    This contrasts to the proposed distance charge which is to be payed individually by millions of drivers. Hence the aggregated administrative burden for both private actors and public administrators is most likely higher. The distance tax must also be payed monthly or yearly, based on the actual driving, in a similar fashion as we currently do with the electricity bills. This also means the drivers have to keep some funds available for the tax payments later.

  • Gas tax is payed according to road usage—the more you drive, the more you pay. Unfortunately, this correspondence is less than perfect. Cars come in different fuel economy and size and stress the roads differently. This is potentially the main objection against funding roads solely by gas tax.

    Heavy truck
    Heavy transport stresses the roads substantially more than small cars. Although trucks burn more fuel than cars, the gas tax may not compensate for the additional stress on roads. Here weight-dependent usage charge may have an advantage.
    By bilbobagweed (formby) [CC BY 2.0 (], via Wikimedia Commons

    But save the road usage charge, gas consumption is still far closer indicator of individual "road consumption" than any other alternative, such as income or sales tax. If gas tax is too crude a measure, how on earth can sales tax be a better one? But sales tax is widely used for funding transportation projects.

  • Gas tax is often claimed to be a burden to the economy. But the picture is more complex. Sure, taxes hurt, but I don't see why should gas tax hurt more than the other taxes, in particular business and payroll taxes. If we introduce it in revenue neutral way, i.e. we lower the other taxes by exactly the same amount as we rise the gas tax, it amounts to redistributing the tax burden from the rest of the economy to large gas users. It is not immediately clear what are the economic implications. Transport intensive sectors will probably lose (but it also depends on what happens with road quality and congestion) while "human-intensive" sectors win from lower income tax. This includes technology companies that rely on a large well-payed workforce. I do not see the effect being much different from that of a better targeted road usage fee.

  • Inflation diminishes the value of both gas tax and road usage charge in a similar way. Unless inflation-indexed, regular political decisions are needed to rise these accordingly. The usage charge possesses a clear advantage here as it does not depend on the vehicles' fuel economy. Gas tax must be adjusted both for inflation and fuel economy, usage charge only for inflation.

  • Finally, many people may dislike the idea of government knowing exactly where and how much we drive. And the corresponding technology itself is not safe either—the ways to screw such meters will probably advance as well.


We do not have to wait until a better technology solves the road funding problems. It may never arrive. Meanwhile, gas tax is a simple and good enough road usage fee. The problem is in politics, not in technology.

Friday, July 3, 2015

Common Arguments Against Hosting Refugees Do Not Justify Strict Immigration Policy: Help some if you cannot help them all

Common Arguments Against Hosting Refugees Do Not Justify Strict Immigration Policy

Three everyday arguments against granting asylum for refugees are "we cannot help everyone", "refugees should be hosted in their neighboring countries", and "we don't want economic migrants". All these claims make a point, but none of these can be used to justify a strict asylum policy. Below, I mainly take the European view but the arguments also apply for other developed economis like the Australia and Israel, and for the middle-income countries, such as Brazil or Dubai as well.


A common argument against granting asylum is that there is a too large number of potential immigrants outside the European borders. As we "we cannot help everyone out there", we should keep our borders firmly closed. Otherwise, the rising human flood will flush away both us and our culture. But this argument is fighting a strawman. Accepting some asylum seekers does not imply we have to open borders for all the potential immigrants. We should think about doing our "fair share", not that we have to help everyone. If EU accepts, say, a million refugees, that is a million humans whose lives are improved. And this is a good thing. One can draw a parallel with other calamities here, many survived holocaust exactly because there were people who were willing to help just a few. If you improve the life of someone, this is a life improved, however large is the number of those you cannot help. Another, more pragmatic reason is that by moving some people out of crowded refugee camps in poor regions we lower the pressure both on the camps and on the regions. Indirectly we help the others.

Water Tank in Al Zaatari Refugee Camp
Water tank in al Zaatari refugee camp. Providing water and sanitation for thousands over extended period is a major logistical challenge and may need a substantial infrastructure put in place.
By Mustafa Bader (Own work) [CC BY-SA 4.0], via Wikimedia Commons

I agree that the preferred location for displaced people is close to their region of origin. From there it is easier to go back once the fighting is over, and cultural similarity helps too. But geographic and cultural proximity is just one piece in the enormous logistic challenge. There are many more variables that matter, in particular the availability of jobs and infrastructure to host a large number of people. Conflicts often occur in poor areas were neighbors can offer little besides a similar language. And countless examples show that cultural similarity is no obstacle for killing. Neighbors often do their fair share. Lebanon (4.5M inhabitants) hosts 1.2 million Syrian refugees. 500 million strong EU is far better able to provide the living necessities for a million newcomers. Poor neighbors' help is necessary. But without proper housing, sanitation, jobs and schools, and the conflict lasting for decades, the tent camps are not a solution.

Irish children during the potato famine
The last major famine in Europe, the Irish Potato Famine, led to a substantial increase of emigration to the U.S.
By James Mahony [Public domain], via Wikimedia Commons

Finally, I don't see a clear difference between refugees and economic migrants. Sure, we have to spend our limited ressources on those who deserve it most. But often poverty is accompanied with fighting, and famine may be even more deadly than war. I would suggest to introduce an immigration lottery, similar to the US green card lottery where everyone may try their luck. Give those who are fleeing war and desperation a substantially better chance to be granted access, but give the others an opportunity too. In this way we avoid drawing too strict lines between humans, and too much desperation among those who were left out.


We can do things the poor regions cannot. We should help some even if we cannot help everyone.

Wednesday, June 24, 2015

Where Do People Meet? Urban Segregation in Cellular Data

Where Do Ethnic Groups Meet?
Ott Toomet, Siiri Silm, Rein Ahas, Erki Saluveer, Tiit Tammaru

Immigrants and ethnic minorities often live more or less separately from the majority population. This fact is sometimes touted as a major problem that hampers social integration. But does the place where we live actually matter? Anecdotal evidence suggests that we do not interact much with our neighbors. Why should we worry then who they are?

To shed more light on this issue we analyzed the spatial behavior of Estonian speaking and Russian speaking population in Tallinn, Estonia. It is an interesting city as it is almost 50-50 split between the corresponding ethnic groups. We used cellphone data for the analysis. Mobile operators always record which antenna talks to our phones, and such data essentially form a spatial track of our activities where one can see our approximate location and time. It is relatively straightforward to analyze the tracks and deduce who were close to each other, and when and where it happened. Looking at the repeated patterns of calls we can also guess where people live and work. In this way we can see who can potentially meet each other, and where such meetings might occur.

So, are Estonian speakers close to Russian speakers in Tallinn? Well, it depends on when. We find that when at home and at work, both groups are substantially segregated. However, this is much less true when people are elsewhere and busy with other tasks, such as shopping, but also during various leisure-time activities. Even more, such free-time segregation is not closely related to the environment in the place of residence and place of work (see the figures). Even those who live in almost completely Estonian or Russian neighborhoods experience a rather mixed free-time environment.

Fig 1. Relationship between free-time meetings and composition of residential neighborhood. Circles and triangles represent the averages across different neighborhoods. For Russians (red triangles), the percentage of Russian speakers ranges between less than 10% to almost 80%, for Estonians (black circles) between 20% and almost 100% (horizontal axis). Despite of living in such different neighborhoods, during free-time both groups meet own-group members for approximately 50-60% of the time.
Fig 2. Relationship between free-time meetings and composition of work neighborhood. The message is similar to that in Figure 1: work neighborhoods vary a lot, but it is not closely associated with our free-time environment.

What do these results tell us? There are several interesting conclusions.

  • residential segregation may be less of a concern than often suggested. We spend much of our active time elsewhere, and much of the time we are at home we sleep.
  • As a typical European city, Tallinn has a dense urban core where a substantial part of these meeting occur. It suggests that a dense vibrant downtown is favorable for bringing together people of different background. The results for Los Angeles may well be different.
  • Finally, we do not know what is behind these meetings. Most of these are probably related to just being close to each other in a crowded city. But so are our relations with our neighbors: most of them we would not even recognize on street. There is need for more analysis on what are the "meaningful places" in terms of where do we actually socialize with people.

The full article is available at

Saturday, April 25, 2015

Mediterranean Migration Crisis: Do Not Blame the Smugglers...

The recent disasters in the Mediterranean have brought immigration and human trafficking to the top of European agenda. EU has responded with a predictable face–lifting proposals—promising to
triple the maritime patrols and tackle the issue "at its root", by attacking human traffickers, and by improving the border policing of the African states (in particular Libya).

Cayuco approached by a spanish Salvamar vessel

But this is not the root of the problem. The main underlying problem is the world inequality, both in humanitarian and economic sense. Too many people are living in a desperate situation, be it because of threat to their lives, or lack of opportunities in the place where they happen to live. And for these people, the smugglers are simply the least bad of the available options.

I stress this again---the traffickers are the best available option for hundreds of thousands of migrants. All these people hope that the traffickers help them to escape death and poverty, and to fulfill their dreams of a better life. They are willing to pay an amount, comparable to the price of Europe-US return flight in business class. What they get for it is a 90-percent chance to cross 200km of sea in a crowded wreckage. Remember also that these people cannot just save this money from their paycheck over a few months, for many of them it amounts to years' of savings. This should remind us what scale of human suffering is out there behind our borders, how desperate are refugees, and what is the role of the smugglers.

This is not to say that the smugglers should not be blamed at all. They still must treat their "customers" in a humane manner. They should inform the migrants about the dangers and opportunities of the trip. They must keep their promises. Slaughtering selected people because of religion or other reasons is plainly criminal. Smugglers should also follow minimal safety and navigation standards. But these problems can be addressed by training, regulation and oversight of the smuggling industry, not by airstrikes. Or even better—by opening a regular ferry line that adheres to the accepted safety rules.

The initiative to improve the border patrolling and crack down the human trafficking in African countries is more like outsourcing the border guarding jobs further away to forces with more dubious human rights record than the European ones. It will not help with the underlying problems, and it will increase human suffering by leaving hundreds of thousands in a desperate situation without the best option to escape they have had up to now. To really address the root cause would mean to ameliorate world inequality, and to pacify Middle-East. This is far beyond what EU (or anyone else) can realistically hope. Unfortunately, the simple and realistic alternative—open the borders to substantially more refugees—will enjoy very little popular support.

So, dear politicians, I understand very well that tackling the root of the problem is simply a fantasy. I also know that the voters do not let you to take any available steps either. But you still can use the right words: Our response will be to build a stronger fence. Because suffering further from our borders is not our problem.

Sunday, April 5, 2015

Water Markets for California

California is parched.  There is little water and all the forecasts indicate that there will be even less of it later in summer.  What are the options to ameliorate the situation?

There is one obvious reform that has not received much public attention: introducing water-markets.  I do not understand why is the market solution almost universally overlooked.  I am even willing to argue that water market is the solution, it may be supplemented with other means but those will remain supplements, adjusting the market where it cannot get it right.

This is not the first dry spell in California.  Dry riverbed in 2009.  By NOAA, [Public domain], via Wikimedia Commons
Instead of markets, we hear about different ad-hoc measures.  But how much can a state save if the restaurants are forced not to serve water to the customers unless they ask for it? Who is going to control whether lawns are watered 2 or 3 days a week?  Why do we need rules that only permit to fill covered pools?  The list goes on-and-on, garden fountains can only be used in case they work on a closed circulation, cars can only be washed with hoses with shutoff nozzles, new developments cannot irrigate with potable water unless drip irrigation systems are used, agricultural water users have to report more water use information to regulators...

There are several issues with such measures.  First, these may not be effective for saving water.  The problem is not washing streets or watering lawns after rain.  The problem is that the population as a whole uses more water than what is available.  It is the total quantity, not the way water is used.  We may prescribe what is the "fair" use but wasteful usage remains an issue even when only spending water in "acceptable" way—we cannot check how many minutes people take shower.  Second, the government cannot decide what is the best use.  Water consumption does not have noteworthy externalities, so it should be left to the individual users to decide what to do with it.  Third, such measures may target the straw-man while leaving the main culprits untouched.  The little data I have suggests that more than 3/4 of water in California (out of what humans are using) goes for irrigation.  As a rule of thumb, agricultural water need is around 1000 times the final mass of the harvest.  So, the "water-tag" of a restaurant meal amounts to 300-1000kg, out of which less than 1/1000 is served in glass...  Maybe we should ban restaurants to serve Californian rice instead?

Markets help to settle all these issues.  Here is a number of steps one has to take to reach fully functioning water markets.
  • Clear water property rights.  The water ownership must be unambiguous, both for reservoirs and groundwater. 
  • Extraction quota for different water sources, set each year by a public institution.  Up to the quota, the owners can sell water to any user.  This amounts to a "cap-and-trade" system.
  • The quota must be tradable.
  • "Pipe-neutrality".  The price must be associated with quantity,  quality, and location of the water, but not how it is used.  If you pay the price, feel free to drink, water your lawn, or wash the car.  Note that this is exactly how the electricity market works.
  • Every household and farm must have water meters.  This also applies to irrigation water.
  • There may be a need for a (temporary) support for those who loose as a result of the new system.  The support must be in the form of cash, not water!
Water meters are simple and ubiquitous.  Photo: AndrĂ© Karwath aka Aka [CC BY-SA 2.5], via Wikimedia Commons

Who are the loosers?  Many will point to farmers but that depends on who will obtain the water rights.  If the farmers will be entitled to a large endowment as they have historically been, they may be the winners instead—selling that water may bring more income than using it on fields.  If, however, the rights are given to someone else, many farms will be immediately out of business.  It is expensive to farm in arid climate.

Finally, I stress here that this reform does not amount to a tax hike.  First, the money for water goes to the government only if the government gets the water rights.  Second, if this is the case, the government should lower taxes, such as income or property tax.  It amounts to shifting government revenues from property and income tax to natural resources.

Friday, February 20, 2015

Tax Breaks for Protecting Landscape

Untouched nature is increasingly scarce.  This is even more true close to big population centers where such areas are of high value. Below I talk mostly of  forests but the ideas are more general.
Old forest.  Many snags and coarse woody debris offer habitat for a wide range of organisms.  Such forests are often suitable for recreational use as there is little undergrowth due to dense canopy above.  Conifer forests of Rattlesnake Ledge, WA
Land is typically taxed based on it's market value.  This approach is simple—it only depends on the size and location of the plot (although determining the value may be tricky).  However, it does not encourage the landowners to preserve the valuable habitats, nor does it encourage it to keep the land open to public.  It implicitly tells that the property owner is the sole decision-maker and does not have to take into account the others' interests.  But natural landscape is valuable not just for the landowner but also for other users, such as leisure trekkers or picnickers, and for many living organisms other than homo sapiens.  In economics parlance, natural landscape possesses positive externalities.

Keeping land open for everyone—for both nature and humans—should be an attractive option.  It can be encouraged by making land tax dependent on the type of usage.  Valuable natural habitats where the public has open access should be free of tax.  In other words, we should not tax land possession but only the "exclusion" of land, using it in a way that does not permit the others (including nature) to benefit from it.

Private property: Harvested natural forest is replaced by a plantation.  The area is made inaccessible both for humans and for large animals.  (Former) temporal forest in Veskimõisa, EE.
This approach will bring a number of changes:
  • The landowners should only pay land tax on such a property that is either not open (like gardens and courtyards) or not natural (like fields).  Forests, natural meadows, and other habitats should be considered as "natural land".  If everyone has free access to these areas and human interference is kept at minimum, the land should be tax-free.  I mean "free access" in legal sense, the owner should not have any obligation to facilitate it through specific infrastructure.
  • In case the landlord takes some of the natural area into non-natural use (say, by logging), then it will immediately be subject to tax.  The tax will decrease over time as the nature take over and the natural/leisure value of the area increases.
  • Analogously, if land that was previously used for non-natural or restricted purpose is left untouched, the tax will fall over years as the value of it grows.
  • If land tax is based on the market value, it implicitly (albeit imperfectly) takes into account how the human value of land depends on location.  Land near the population centers is expensive, and hence the potential land tax will be high.  Such a tax exemption encourages creation of publicly open natural areas close to cities more than it does that in far-lying locations.
  • In order to be eligible for a lower tax rate, the natural value of the land must be re-assessed. The landowner should apply for re-evaluation, perhaps no more frequently than once in 5-10 years.  Such evaluation reports should be made public to decrease the room for corruption.
  • Perhaps the largest problem with this proposal is the need to asses the non-market value of land.  It is a vague concept and leaves room for interpretation.  Simpler but less precise rules may be preferred instead.
Natural resources are a strong incentive to restrict public access.  Diamond area in South Africa, 1940s.
Who are the winners and the losers?  First, I don't think this measure would be massively used and hence the effects will be small. If it will, however, it may harm the logging and wood processing industry. Second, if the tax income from certain plots decreases, it must rise elsewhere (not just on land).  So it amounts to trading more nature for higher taxes.  Obviously, the winners are those who benefit from the nature and the losers are those who do not.  Finally, the largest gains are experienced by property owners who already keep their natural land open for everyone.