最近的比特币市场，按我看来，既不是熊市也不是牛市，而是上窜下跳的猴市。比特币先跌到$6000 USD之下，然后市场传言美国SEC有90%概率会通过比特币ETF，一下子比特币升到$8500 USD，接着又有消息SEC拒绝了一个比特币ETF申请也可能会陆续拒绝其他的申请，比特币就跌回了$8000 USD以下。
今天我们就介绍一个在比特币交易中很有用的参考指数：恐惧和贪婪指数（Crypto Fear & Greed Index），其网站链接是：https://alternative.me/crypto/fear-and-greed-index/
这个指数为0时表示极度恐惧，100则表示极度贪婪（Zero means "Extreme Fear", while 100 means "Extreme Greed"）。从上面的历史数据中可看出，当这个指数低于20的时候，是个比较好的买入机会，而当这个指数超过60就基本可以考虑卖了。
1）波动性：Volatility (25 %)
We’re measuring the current volatility and max. drawdowns of bitcoin and compare it with the corresponding average values of the last 30 days and 90 days. We argue that an unusual rise in volatility is a sign of a fearful market.
2）市场交易量：Market Momentum/Volume (25%)
Also, we’re measuring the current volume and market momentum (again in comparison with the last 30/90 day average values) and put those two values together. Generally, when we see high buying volumes in a positive market on a daily basis, we conclude that the market acts overly greedy / too bullish.
3）社交媒体热度：Social Media (15%)
While our reddit sentiment analysis is still not in the live index (we’re still experimenting some market-related key words in the text processing algorithm), our twitter analysis is running. There, we gather and count posts on various hashtags for each coin (publicly, we show only those for Bitcoin) and check how fast and how many interactions they receive in certain time frames). A unusual high interaction rate results in a grown public interest in the coin and in our eyes, corresponds to a greedy market behaviour.
Together with strawpoll.com (disclaimer: we own this site, too), quite a large public polling platform, we’re conducting weekly crypto polls and ask people how they see the market. Usually, we’re seeing 2,000 - 3,000 votes on each poll, so we do get a picture of the sentiment of a group of crypto investors. We don’t give those results too much attention, but it was quite useful in the beginning of our studies. You can see some recent results here.
The dominance of a coin resembles the market cap share of the whole crypto market. Especially for Bitcoin, we think that a rise in Bitcoin dominance is caused by a fear of (and thus a reduction of) too speculative alt-coin investments, since Bitcoin is becoming more and more the safe haven of crypto. On the other side, when Bitcoin dominance shrinks, people are getting more greedy by investing in more risky alt-coins, dreaming of their chance in next big bull run. Anyhow, analyzing the dominance for a coin other than Bitcoin, you could argue the other way round, since more interest in an alt-coin may conclude a bullish/greedy behaviour for that specific coin.
We pull Google Trends data for various Bitcoin related search queries and crunch those numbers, especially the change of search volumes as well as recommended other currently popular searches. For example, if you check Google Trends for "Bitcoin", you can’t get much information from the search volume. But currently, you can see that there is currently a +1,550% rise of the query „bitcoin price manipulation“ in the box of related search queries (as of 05/29/2018). This is clearly a sign of fear in the market, and we use that for our index.