We have tried learning various methods to read data in Colab, including

  1. read data from an url by pandas (Yiu, 2021a);
  2. read data from Yahoo Finance by web.DataReader (Yiu, 2021a);
  3. read data from google drive by drive.mount (Yiu, 2021b); and
  4. read data from geopandas’ datasets (Yiu, 2021c).

However, all these methods rely on the data structure prepared by the data sources. The best way is of course to download from the raw data with the data structure defined by yourself, such as getting data from an API (Application Programming Interface).

But then it is quite complicated and difficult to code…


One of the most important tools for data visualisation is mapping tools, such as GIS. But advanced GIS software can be expensive, and even if some of them are free to download, but it may not be user-friendly and hard to program. This article shows a simple program by using geopandas in Co-lab to draw the following world map shaded by GDP per capita with a scale bar. (Figure 1).

Figure 1 A World Map of GDP per capita

To make it very simple, I simply do the following three tasks:

  1. read a shape file of countries with population and gdp data and a vector file of capitals from…


Nowadays bankers and real estate agents can almost immediately get a guesstimate of a house price by a Mobile-App by specifying housing attributes. It facilitates mortgage borrowers to know better how much can they borrow from the bank. A Residential Automated Valuation Model (AVM) runs a machine learning algorithm that accounts for the house’s size, number of rooms, housing quality attributes, etc. to make an up-to-date house price predictions. Simply put, it is a house price estimator (Figure 0).

Figure 0 An AVM — house price estimator by inputting housing attributes

Last week, we have discussed how to predict house prices by FB Prophet (Yiu, 2021a), which is a time series predictor…


In the past five years, many of my economic forecasts have come true. If it is just one or two forecasts that are accurate, which can be achieved by chance, but if all the six predictions come true, it is extremely unlikely that it is purely by luck.

The following is a summary of the six forecasts: global recession; construction cost declines; property price falls; office vacancy rate rise; gold price rise; and global deflation.

The first is the prediction of the global economic recession. It was first warned that Hong Kong’s economy might enter a recession in five years…


PropTech is a buzzword that different people are talking about different things. The 2017 definition emphasizes a “technology-driven innovation in the data assembly, transaction, and design of buildings and cities”. (Baum & Dearsley, 2017) and defined it as the interactions of Real Estate Fintech, Smart Building Technologies, and the Shared Economy in the Property industry. But then they further add ConTech (such as Computer-aided design) and LegalTech (such as smart contracts) into the schematic in 2020 (Braesemann & Baum, 2020), as shown in Figure 1.

Figure 1 What is PropTech. Source: Braesemann & Baum (2020)

However, this definition can result in an identity crisis as PropTech is defined as a…


There are many forecasting tools available in the market, even Excel worksheet also provides a simple forecasting function, which I have shown how to use it (Yiu, 2019). Other more sophisticated software can provide ARIMA and HP Filter methods for forecasting, but they can be costly.

I learned that FB Prophet provides an open source code and free forecasting tool in R or Python. It allows more detailed parameter settings for making forecasts including three additive components: trend, seasonality and holidays. For more details, one may refer Lyla (2019).

I am learning to use FB Prophet and here is my…


Indirect real estate investment (IREI) generally refers to the trading of real estate-related investment tools in the stock market. The most common one is Real Estate Investment Trust (REITs). According to NAREIT (2021) website, “REITs allow anyone to invest in portfolios of real estate assets … through the purchase of individual company stock… The stockholders of a REIT earn a share of the income produced.” Since their assets and returns are related to the price and rental income of real estate, they are often referred to as Indirect Real Estate Investment.

Direct Real Estate Investment (DREI), in contrast, involves direct…


With the advancement of online platforms and the popularity of sharing economy (or collaborative economy), various new business models of subletting property have been developed. The most well-known three models I suppose are Airbnb, Danke and WeWork. Here I use the names as a representation of the business models. For example, Airbnb is only one of the peer-to-peer (P2P) platforms for short-term accommodation. There are many other similar platforms, both online and offline, under different brands that are also engaging in the same business.

I am not going to discuss the details of their business models as I think many…


Modern society is stressful, anxiety and depression are at alarming proportion. We urgently need to build up our mental resilience. I put forward a novel model in this article as a hypothesis for further testing.

Positive and Negative thoughts

Figure 1 shows the model, the horizontal axis refers to the positive and negative thoughts. Positive thoughts include happiness, confidence, motivation, success, relaxation, etc. Negative thoughts are worry, fear, anxiety, panic, threat, depression, hatred, anger, regret, etc.

People try hard to avoid negative thoughts and like to have positive ones. ironically, the harder you try to avoid negative thoughts, the worse they become. Negative thoughts…


Since December 2019, the COVID-19 pandemic has plagued the world for more than a year now. The total number of confirmed cases has passed the 10 million mark, and the death toll has reached 2.44 million. The current global case-fatality ratio (CFR) is about 2.2%.

CFR is defined as the number of deaths divided by the number of confirmed cases.

The good news is the daily number of confirmed cases around the world has shown an obvious sign of decline. Figure 1 shows that the daily number of confirmed cases has dropped from the peak of 733,764 cases on January…

ecyY

ecyY — easy to understand why, easy to study why. Finding the truths scientifically is the theme.

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