# Research scientist machine learning Interview Questions

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Research Scientist Machine Learning interview questions shared by candidates### More on machine learning algorithms. Easy coding question

1 Answers↳

Can you provide more details on the questions please?

### You have a singly linked list, how would you find the median?

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Sort it (choose an algorithm), calculate index for median, loop over next based on index. They will want to actually discuss implementation (i.e. use a for loop, traverse next ptr, etc.). You should also know algorithmic complexity (big-O notation). Less

### After you have decided which features to use, describe the process of constructing feature-vectors

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It was almost all about tf-idf vectorizer

### Describe a project where there were multiple alternatives from which to choose in implementing it.

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Gave examples from work history.

### '''Question 1: Given a sorted but rotated array, and a target, find the location of the target in the array. If the target is not in the array, returns -1 1) INPUT: [3,6,7,1,2], target = 1 OUTPUT: 3 2) INPUT: [3,6,7,1,2], target = 9 OUTPUT: -1 '''

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def search(A, target): if target == None: return -1 #if not target: # return -1 #riht I needed to address this! try: target = int(target) except ValueError: return -1 l=0 n = len(A) r = n-1 while l<=r: middle=l+((r-l)/2) if A[middle] == target: return middle if A[l] <= A[middle]: if ((A[l]<= target) and (target Less

### How do you implement feature selection in text classification?

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Mutual information / chi-squared criteria