# Descriptive Statistics (Data Analytics)

> Mean vs median, variance, standard deviation, normal distribution, skewness, correlation vs causation, sampling bias, percentiles

- 20 interview questions
- Junior
- [Interview Questions: Data Analytics](https://sharpskill.dev/en/technologies/data-analytics/interview-questions.md)

## 1. Which measure of central tendency represents the value that divides a sorted dataset into two equal halves?

**Answer**

The median is the middle value of a dataset sorted in ascending order. It separates exactly 50% of lower values from 50% of higher values. Unlike the mean, the median is not affected by extreme values, making it a more robust indicator for skewed distributions such as income or real estate prices.

## 2. What is the fundamental difference between the mean and the median?

**Answer**

The mean takes all values into account and is therefore sensitive to extreme values (outliers), while the median depends only on the central position of sorted data. For example, if five salaries are 30k, 35k, 40k, 45k, and 500k, the mean is pulled upward by 500k (130k), whereas the median stays at 40k, better reflecting the group's reality.

## 3. What is the mode in a dataset?

**Answer**

The mode is the value that appears most frequently in a dataset. A dataset can be unimodal (one mode), bimodal (two modes), or multimodal (multiple modes). The mode is the only measure of central tendency that can be used with categorical data, such as favorite color or best-selling product category.

## 17 more questions available

- What does the variance measure in a dataset?
- What is the relationship between variance and standard deviation?

Sign up for free: https://sharpskill.dev/en/login

## Other Data Analytics interview topics

- [Google Sheets - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/google-sheets-basics.md): 20 questions, Junior
- [Google Sheets - Advanced Formulas](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/google-sheets-advanced.md): 20 questions, Junior
- [SQL - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-basics.md): 25 questions, Junior
- [SQL - Aggregations and Grouping](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-aggregations.md): 20 questions, Junior
- [SQL - Joins](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-joins.md): 20 questions, Junior
- [BigQuery - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/bigquery-fundamentals.md): 20 questions, Junior
- [Data Cleaning](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/data-cleaning.md): 20 questions, Junior
- [KPIs and Business Metrics](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/kpis-metrics.md): 20 questions, Junior
- [Zapier and No-Code Automation](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/zapier-automation.md): 20 questions, Junior
- [Data Visualization Principles](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/data-viz-principles.md): 20 questions, Junior
- [Python & Pandas - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/python-pandas-basics.md): 20 questions, Junior
- [Google Sheets - Automated Dashboards](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/google-sheets-dashboards.md): 20 questions, Mid-Level
- [SQL - Subqueries and CTEs](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-subqueries-ctes.md): 20 questions, Mid-Level
- [SQL - Window Functions](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-window-functions.md): 20 questions, Mid-Level
- [BigQuery - Advanced Features](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/bigquery-advanced.md): 20 questions, Mid-Level
- [Data Modeling](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/data-modeling.md): 20 questions, Mid-Level
- [Funnel and Conversion Analysis](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/funnel-analysis.md): 20 questions, Mid-Level
- [Cohort and Retention Analysis](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/cohort-retention.md): 20 questions, Mid-Level
- [Google Tag Manager and Tracking](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/gtm-tracking.md): 20 questions, Mid-Level
- [APIs and Webhooks](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/apis-webhooks.md): 20 questions, Mid-Level
- [dbt - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/dbt-fundamentals.md): 20 questions, Mid-Level
- [AB Testing and Applied Statistics](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/ab-testing.md): 20 questions, Mid-Level
- [Looker Studio (Google Data Studio)](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/looker-studio.md): 20 questions, Mid-Level
- [Power BI - Fundamentals](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/power-bi-fundamentals.md): 20 questions, Mid-Level
- [SQL - Advanced Analytical Queries](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/sql-advanced-analytics.md): 20 questions, Senior
- [dbt - Advanced Features](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/dbt-advanced.md): 20 questions, Senior
- [Power BI - DAX and Advanced Dashboards](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/power-bi-dax.md): 20 questions, Senior
- [Python Analytics - Advanced Analysis and ML](https://sharpskill.dev/en/technologies/data-analytics/interview-questions/python-analytics-advanced.md): 20 questions, Senior

---

Source: SharpSkill (https://sharpskill.dev), tech interview preparation for your real stack.
HTML version of this page: https://sharpskill.dev/en/technologies/data-analytics/interview-questions/descriptive-statistics