brief summary
基于地理位置不同，地区之间的资源，经济，信息等不对称。使得实物类，虚拟类，甚至信息的价值不同，这是物物交换的基础。交易者本身对物质，信息，资源的拥有的富余程度也决定了这样东西在他心中的价值。不依赖现有的货币体系，不依赖现有的市场定价模式，去中心化一切建立在交易不同双方的期望价值。交易＝社交，天然的社交属性，形成规模时，定会对现有的经济与货币体系造成冲击。最重要的一点是让资源的所有者拥有真正的定价权，换取他自己觉得值得任何资源。
The act of trading goods and services between two or more parties without the use of money. Bartering benefits individuals, companies and countries that see a mutual benefit in exchanging goods and services rather than cash, and it enables those who are lacking hard currency to obtain goods and services.
对于物物交换本质的解释：
http://en.wikipedia.org/wiki/Barter
https://hbr.org/2012/09/the-exploding-business-of-bart
http://www.investopedia.com/terms/b/barter.asp
对于物物交换的限制与优势
Limitations
Barter's limits are usually explained in terms of its inefficiencies in easing exchange in comparison to the functions of money:
＊Need for presence of double coincidence of wants
For barter to occur between two people, both would need to have what the other wants.
＊Absence of common measure of value
In a monetary economy, money plays the role of a measure of value of all goods, so their values can be measured against each other; this role may be absent in a barter economy.
＊Indivisibility of certain goods
If a person wants to buy a certain amount of another's goods, but only has for payment one indivisible unit of another good which is worth more than what the person wants to obtain, a barter transaction cannot occur.
＊Lack of standards for deferred payments
This is related to the absence of a common measure of value, although if the debt is denominated in units of the good that will eventually be used in payment, it is not a problem.
＊Difficulty in storing wealth
If a society relies exclusively on perishable goods, storing wealth for the future may be impractical. However, some barter economies rely on durable goods like pigs or cattle for this purpose.
Advantage
＊Direct barter doesn't require payment in money (when money is in short supply) hence will be utilized when there is little information about the credit worthiness of trade partners or there is a lack of trust.
＊The poor cannot afford to store their small supply of wealth in money, especially in situations where money devalues quickly (hyperinflation).
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一些例子
例1：一根针换一座别墅（这个例子非常有名，大家可以到网上搜索一下）
例2：二锅头换帝王蟹（实际案例）
例3：清凉油换钻石（实际案例）
可参考货币的演化进化史
市场的插入点
旅游，旅游的人抱有对另一目的地的了解，社交意识强烈，互换意愿和能力都强，对得失的计较感会相对降低，即需要的回报一般来讲会比实际低，这一部分的冷启动人群就可以利用国内外的旅游社交网站，对这类网站的后段流量（行程确定安排好以后就没这些网站什么事情例），我们对这些流量再次有效利用。
1.基于出行的市场容量计算
基于全世界主流交通工具运力能力
空运 http://www.garfors.com/2014/06/100000-flights-day.html
陆运
海运
2. 交换的种类
可以是一切有价值的资源置换
定义：
a.实物，拥有实体，物理形态
b.服务，无实体，虚拟的形态，可以是信息，可以是一次导游服务，可以是一次课程，可能是一次按摩
实物 交易 实物
实物 交易 服务
实物 交易 实物＋服务
3.Metrics
个人
互换意愿强烈程度
资源拥有的富余程度
对需求资源的渴望程度
对需求资源的急切程度
平台
匹配，与优质的匹配是平台所追求的第一任务
交易，其次再是交易比数
沉淀，如何让平台更好的体现社交化，与沉淀用户感情
4.平台需要承担的-->信任体系
认证（实名，社交体系验证）
信誉（个人交易记录，及reviews）
匹配（最优交易的匹配）
交易（锁定，安全）
范围（交易内容与国家法律体系的冲突等，如税收，避免洗黑钱，违禁品。可参考比特币开始这么久，各国相关监管政策出台）
