# Data Analyst Interview Preparation Guide **Download PDF** Add New Question

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Data Analyst frequently Asked Questions in various Data Analysis job Interviews by interviewer. The set of questions here ensures that you offer a perfect answer posed to you. So get preparation for your new job hunting

## 31 Data Analysis Questions and Answers:

### 1 :: What is data analysis?

Data analysis is the process of systematically applying statistical and/or logical techniques to describe and illustrate, condense and recap and evaluate data.

### 2 :: What is average?

The average or the arithmetic mean is defined as the sum of all measurements divided by the number of observations. For example, the average of the numbers 10, 12 and 22 is 14.6 because 10+12+22=44 and there are three observations, so 44 divided by three is 14.6. When there are only numbers involved, an average problem is quite simple.

### 3 :: Name the two concepts of average?

★ Mode

★ Median

★ Median

### 4 :: List some topics which are include in data analysis?

There are many data analysis topics that you should be familiar with. Many of them are described here. They include:

★ Averages

★ Box Plots

★ Normal Distributions

★ Counting Methods - Sets

★ Averages

★ Box Plots

★ Normal Distributions

★ Counting Methods - Sets

### 5 :: Tell me about median?

The median of a set of numbers is the number that is exactly half way between the largest and smallest number, when the numbers are arranged from smallest to largest.

### 6 :: Please tell me what is a box plot?

A box plot graphically displays groups of numerical data through their five-number summaries: the smallest observation (sample minimum), lower quartile (Q1), median (M), upper quartile (Q2) and largest observation (sample maximum).

The box plot is often called a "whisker" plot because "whiskers" extend outward from the boxes to the least and greatest values.

The box plot is often called a "whisker" plot because "whiskers" extend outward from the boxes to the least and greatest values.

### 7 :: List the properties which are satisfied by the normal distributions?

All normal distributions satisfy the following properties:

★ Approximately 68% of the observations fall within 1 standard deviation of the mean

★ Approximately 95% of the observations fall within 2 standard deviations of the mean

★ The mean, median and mode of the data are nearly all equal

★ Approximately 68% of the observations fall within 1 standard deviation of the mean

★ Approximately 95% of the observations fall within 2 standard deviations of the mean

★ The mean, median and mode of the data are nearly all equal

### 8 :: Define inclusion-exclusion principle in data analysis?

A counting principle that you may appear on a data analysis question is the inclusion-exclusion principle, which states that the number of elements in the union of two finite sets equals the count of the members in the two sets minus the number of elements in the intersection of the two sets. The number of elements in a set is denoted using two parallel lines, ||. Using set notation, the inclusion-exclusion principle for sets D and E is written as the following:

|D∪E| = |D| + |E| - |D∩E|

|D∪E| = |D| + |E| - |D∩E|

### 9 :: Do you know what is data analysis?

Data analysis is the process of systematically applying statistical and/or logical techniques to describe and illustrate, condense and recap and evaluate data.

### 10 :: What is mode in data analysis?

The mode of a set of numbers is the number that appears most often.