# Articles by Statistics & R

### Dropping levels in a factor variable

March 3, 2021 |

Assume you have a data frame (df) for patients taking a specific drug. The data consists of a factor variable (Drug) and a numeric variable (N_patients). Drugs N_patients Drug 1 50 Drug 2 40 Drug 3 23 Drug 4 92 Drug 5 70 Later on you filter the data frame for specific levels in the factor variable and ... [Read more...]

### Shinyapp to monitor Covid-19 cases, deaths, recoveries and vaccinations

January 30, 2021 |

The data pertaining to cases, deaths and recoveries is pooled from Johns Hopkins University Center for Systems Science and Engineering (JHU CCSE). Vaccination data is pooled from Our world in data. Both sources update the data sets on a daily basis an...

### Covid-19 Vaccination Race

January 14, 2021 |

It took Scientists ~ 10 months to come up with the vaccine against Covid-19. Now its up to governments and people’s awareness to help eradicate the virus. For this reason this shinyapp helps monitor the vaccination status of the countries that have in...

### Chi-square tests

January 9, 2021 |

Chi-square test is a statistical method used for analysis of categorical data. There are 2 types: 1. Goodness of fit Known as: * Chi-square for 1 sample * Chi-square for given proportions Purpose : Comparing the observed frequency to the expected... [Read more...]

### Installing older version of a package

January 4, 2021 |

In many situations when you install a new package, R will ask you whether you want to update to the updated versions of existing packages in your library. However, the main problem is sometimes in the updated version, a certain function might have bee... [Read more...]

### Comparing means of two independent groups

December 25, 2020 |

This shinyapp helps researchers/students to decide on the type of test to be done when having 2 groups. Sometimes it is possible to forget a certain assumption. For this reason this app helps in providing more confidence for choosing the right test. [Read more...]

### Covid-19 Shinyapp

December 24, 2020 |

The data displayed by this {shinyapp} is taken from Johns Hopkins University Center for Systems Science and Engineering (JHU CCSE). The raw data is available on {Github}. The data is updated on daily basis. Packages needed for the app: library(easypac...