Well, first a degree from ISI or IIM cannot be compared and evaluated. Because both institutes are prestigious and different from each other. Now, coming to the degree that we are talking about, it is better to have a degree in Statistics rather than in MBA, because the core of Data Science, is Statistics rather than Management studies. So, when compared with these two, it will be beneficial for you if you have a degree in Statistics, you will be able to master Data Science better.
But people with MBA degrees, also break into Data Science so, it cannot be said that an MBA degree will be of no use. It is certainly very useful if you are associating more with business aspects, but when compared, it is of lower relevance that is it. So, we can conclude having M.Stat. is better than having MBA, if you are more centered around the core concept of Data Science, but not so if you are associating with the Business domain. If you wish to get started with Data Science right away, check out the YouTube video on the data scientist.
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