It depends a lot on your budget. Some things to consider: laptop weight (if you are going to carry it around a lot), if you are comfortable with buying reconditioned laptops (which tend to be cheaper, but are usually scratched or contain usage marks)... Overall, I'd recommend you looking into Lenovo Thinkpads or Dell Latitude, usually they offer a good resource to price ratio.

There is no real way to suggest specific products, as it depends on affordability, location, availability etc. If you are likely to work with large amounts of data, data processing and data analysis you would likely benefit from good RAM, strong multi-core CPU, SSD harddrive with good ability to read/write quickly.