R Interview Questions | Eklavya Online

# R Interview Questions

## Explain Histogram.

A histogram is a type of bar chart which shows the frequency of the number of values which are compared with a set of values ranges. The histogram is used for the distribution, whereas a bar chart is used for comparing different entities. In the histogram, each bar represents the height of the number of …

## Explain Pie chart in R.

R programming language has several libraries for creating charts and graphs. A pie-chart is a representation of values in the form of slices of a circle with different colors.

## Explain Time Series Analysis.

Any metric which is measured over regular time intervals creates a time series. Analysis of time series is commercially important due to industrial necessity and relevance, especially with respect to the forecasting (demand, supply, and sale, etc.). A series of data points in which each data point is associated with a timestamp is known as …

## Explain Random Forest.

The Random Forest is also known as Decision Tree Forest. It is one of the popular decision tree-based ensemble models. The accuracy of these models is higher than other decision trees. This algorithm is used for both classification and regression applications.

## Explain Chi-Square Test

The Chi-Square Test is used to analyze the frequency table (i.e., contingency table), which is formed by two categorical variables. The chi-square test evaluates whether there is a significant relationship between the categories of the two variables.

## Give names of visualization packages.

There are the following packages of visualization in R: Plotly ggplot2 tidyquant geofacet googleVis Shiny

## Explain S3 and S4 systems.

In oops, the S3 is used to overload any function. So that we can call the functions with different names, and it depends on the type of input parameter or the number of parameters, and the S4 is the most important characteristic of oops. However, this is a limitation, as it is quite difficult to …

## Define MATLAB and party packages.

This package includes wrapper functions and variable which are used for replicating Matlab function calls.

## Define cluster.stats() and pvclust() function().

The cluster.stats() function define in the fpc package that provides a method for comparing the similarity of two cluster solutions using different validation criteria, and the pvclust() function is defined in the pvclust package that provides p-values for hierarchical clustering.

## What is the full form of SEM and CFA?

CFA stands for Confirmatory Factor Analysis, and SEM stands for Structural Equation Modeling.