Business Analytics Mid-Term Exam

What is the main purpose of R in business analytics?

• Web development

• Data analysis and visualization

• Video editing

• Game development

Answer explanation

The main purpose of R in business analytics is data analysis and visualization. It provides powerful tools for statistical computing and graphical representation, making it essential for interpreting complex data.

What does EDA stand for?

• Easy Data Access

• Exploratory Data Analysis

• Exploratory Data Allocation

• Efficient Data Allocation

Answer explanation

EDA stands for Exploratory Data Analysis, which is a crucial step in data analysis that involves summarizing the main characteristics of a dataset, often using visual methods. The other options do not accurately represent this concept.

Which company uses data to recommend products to customers?

• Alibaba

• Baidu

• Tencent

• JD.com

• All do

Answer explanation

All listed companies, including Alibaba, Baidu, Tencent, and JD.com, utilize data analytics to recommend products to customers, making them all correct choices.

What is the primary tool used for creating graphs in R?

• dplyr

• tidyr

• ggplot2

• stats

Answer explanation

The primary tool for creating graphs in R is ggplot2. It provides a powerful and flexible system for building visualizations based on the Grammar of Graphics, making it the preferred choice for data visualization in R.

What does the Central Limit Theorem say about large samples?

• They are always normally distributed.

• The sampling distribution of the mean approaches normality as sample size increases.

• They always have outliers.

• They are always skewed.

Answer explanation

The Central Limit Theorem states that as the sample size increases, the sampling distribution of the mean becomes approximately normal, regardless of the original population distribution. Thus, the correct choice is that it approaches normality.

What does 'data cleaning' involve?

• Fixing missing values and removing errors

• Creating new variables

• Adding random data points

• Ignoring incorrect data

Answer explanation

Data cleaning primarily involves fixing missing values and removing errors to ensure the dataset is accurate and reliable. This is essential for effective data analysis, making it the correct choice.

When is the binomial distribution appropriate?

• For fixed number of independent trials with two possible outcomes

• For counting random events in an interval

• For continuous measurements

• For time between events

Answer explanation

The binomial distribution is appropriate for scenarios with a fixed number of independent trials, each having two possible outcomes (success or failure). This distinguishes it from other distributions that handle different conditions.

What is a histogram best used for?

• Showing relationships between two variables

• Showing the distribution of one variable

• Comparing categories

• Showing time-based trends

Answer explanation

A histogram is best used for showing the distribution of one variable by displaying the frequency of data points within specified ranges, making it easy to visualize how values are spread across different intervals.

What is the main goal of probability in business analytics?

• To predict exact future outcomes

• To estimate the likelihood of different events

• To create visualizations

• To clean data

Answer explanation

The main goal of probability in business analytics is to estimate the likelihood of different events. This helps businesses make informed decisions based on potential outcomes rather than predicting exact future results.

What is survivorship bias in business analysis?

• It only considers failed cases

• It eliminates all bias

• It has no effect on analysis

• It only considers successful cases while ignoring failures

Answer explanation

Survivorship bias occurs when analysis focuses only on successful cases, overlooking failures. This can lead to misleading conclusions, as it ignores valuable insights from unsuccessful attempts.