Module 2.4.2 Quiz - Getting started with Data Gathering and Investigation Answers
1. What term describes the key characteristics that are observed or measured as part of an experiment or analysis?
- variable
- data set
- statistics
- population
Explanation: Variables are the key characteristics that are measured or observed as part of an experiment or an analysis.
2. Match the variable with the description.
Place the options in the following order:
| Ordinal | qualitative values in order of ranking |
| Nominal | qualitative values based on identity of the object |
| Continuous | quantitative values with infinite range |
| Discrete | quantitative and finite set of values |
3. What category of variables includes nominal or ordinal variables?
- numerical
- categorical
- ratio
- interval
Explanation: Variables are classified as either categorical or numerical. Categorical variables include nominal and ordinal variables.
4. Which statement is an accurate description of discrete variables?
- Discrete variables are qualitative and consist of two or more categories in which order matters.
- They are quantitative with a continuous range of values.
- They are quantitative with a finite set of values.
- They are qualitative and consist of two or more categories of values in which order does not matter.
Explanation: Variables are either categorical or numeric. Numerical variables are qualitative and are either continuous or discrete. Discrete variables are those from a finite set of values such as the number of users on the network.
5. Match the variable with the type of value.
Place the options in the following order:
| nominal | eye color |
| ordinal | student class rank |
| continuous | sales volume |
| discrete | number of users |
6. Which statement describes SQL?
- It is a visual analytics platform for exploring, analyzing, and managing data.
- It is a scripting language for creating dynamic web pages based on social media.
- It is a Google open-source product suitable for small datasets and quick data analysis.
- It is a powerful data management language that allows data analysts to interact with data stored in relational databases.
Explanation: Structured Query Language (SQL) is a powerful database management language that allows data analysts to interact with data that is stored in relational databases. SQL is a standard query language for many database systems.
7. Which statement describes Tableau?
- It is an AWS product suitable for small datasets and quick data analysis.
- It is a visual analytics platform for exploring, analyzing, and managing data.
- It is a scripting language for creating dynamic web pages based on data sets.
- It is an online platform for data professional to share projects about big data collection and analysis.
Explanation: Tableau is a visual analytics platform for exploring, analyzing, and managing data. It is a data analytics market leader due to the depth and quality of its data visualizations.
8. Which two statements describe the Kaggle web site? (Choose two.)
- It provides many data sets with minimum charges.
- It provides many coding samples for creating dynamic advertisement products.
- It offers community machine learning competitions among data science enthusiasts.
- It enables data analysis tools integration such as Excel, SQL database, and Tableau.
- It is an online community for data scientists and machine learning enthusiasts to share ideas.
Explanation: Kaggle is an online community for data scientists and machine learning enthusiasts to share ideas, get inspired, and compete with other data science enthusiasts to solve machine learning challenges. One of the useful resources available on Kaggle are the publicly available data sets.
9. A data analyst is performing data cleaning on an Excel spreadsheet that contains collected data. Which Excel function would the analyst use to find integer data that is larger than expected?
- MIN
- MAX
- Trim
- Sort
Explanation: Prior to performing data analysis, the data must be cleaned. Data cleaning involves removing or updating information that is incomplete, incorrect, improperly formatted, duplicated, or irrelevant. The Excel MAX function can be used to find the largest number in a data set.
10. A data analyst is performing data cleaning on an Excel spreadsheet that contains collected data. The data records have been marked with mixed formatting. The analyst wants to remove all formatting and reformat data. Which operation should the analyst perform to remove current formatting?
- Highlight data range -> Home tab -> Clear -> Clear Formats
- Home tab -> Clear Formats -> Highlight data range -> Clear All
- Highlight data range -> Home tab -> Clear Formats -> Clear All
- Home tab -> Clear Formats -> Clear All -> Highlight data range
Explanation: The steps to remove formatting of cells in Excel are:
- Highlight the data range desired to have formatting removed.
- Click the Home tab.
- Select Clear in the Editing portion.
- Select Clear Formats in the Clear drop-down menu.
