Test Drive of VolksWagan ID 4 and Ford Mach E

As Tesla stock owner, I decided to have a test drive VolksWagon ID 4 and Ford Mach E to evaluate my long position in Tesla. I am located in San Jose bay area. My experience is both cars are very good car and their experiences significantly reduce the transition efforts from gaosline to EV, compared with Tesla. Instead of being a risk to Tesla (at least for coming few years), I would say it is a risk to other models of Volkswagon and Ford.

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Compute Discounted Cash Flow for Buying a House as Investment

In this post, I apply DCF to evaluate whether it is a good idea to buy a house as investment. Here I use the numbers for a typical townhouse in bay area. Based on my analysis here, it may not be a good investment to buy a house for rent in Bay area–it could take more than 40 years to pay back your investment from rent, if doesn’t consider the value of selling house at the end of investment period. This could be even worse, if you could not use mortgage when buying the house.

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End-to-End Object Detection with Transformers

DETR still uses CNN for feature extration and then use transformer to capture context of objects (boxes) in images. Compared with previous object detection model, e.g., MaskRCNN, YOLO, it doesn’t need to have anchor and nonmaximal suppression, which is achived by transformer. Besides DETR could be directly applied for panoptic segmentation (joint semantic segmentation and instance segmentation).

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