# Articles by Method Matters

### Bayesian Regression Analysis with Rstanarm

September 1, 2021 |

In this post, we will work through a simple example of Bayesian regression analysis with the rstanarm package in R. I’ve been reading Gelman, Hill and Vehtari’s recent book “Regression and Other Stories”, and this blog post is my attempt to apply some of the things I’ve ...

### Mi Band 5 vs. Mi Band 5: Convergent Validity of Step Count Measurements with R

May 30, 2021 |

In this post, we will once again return to the concept of convergent validity, and examine data from two fitness trackers to determine the extent to which their measurements agree. We will also examine the impact of the position of the tracker on the wrist, and see whether this makes ...

### How Do You Order Songs on an Album? Album Sequencing & Song Tempo Across Musical Genres

March 28, 2021 |

In this post, we will return to a dataset we examined previously: information describing over 10,000 songs in my personal music collection. We’ll examine the tempo (e.g. the speed) at which songs are played, and analyze the tempo of songs across the length of an album - overall and ...

### The Impact of the COVID-19 Pandemic on My Walking Behavior in 2020

January 25, 2021 |

In this post, we will take a look back at 2020, and analyze my step count data to understand some of the impacts that the COVID-19 crisis had on my walking behavior during that crazy year. The Data Step Counts & Measurement Devices The step count data come from 2 sources in 2020 - ...

### Extracting Step Count, Heart Rate, and Activity Data From the Mi-Band 5: A Guide with Gadgetbridge and R

December 13, 2020 |

In this post, we will see how to extract step count, heart rate, and activity data from the Xiaomi Mi-Band 5 tracking device. The Mi-Band 5 is a relatively inexpensive personal tracker that was released in July of 2020. I bought one in August after my ...

### Analyzing the Harmonic Structure of Music: Modes, Keys and Clustering Musical Genres

November 23, 2020 |

In this post, we will examine the harmonic properties of songs in my music collection. We will focus on two primary aspects of the music: the mode (e.g. whether the songs are played in major or minor keys), and the musical key itself (e.g. C major, D minor, ...

### Word Clouds for Management Presentations: A Workflow with R & Quanteda

June 7, 2020 |

In this post, we’ll take a look at a basic text visualization technique we’ve seen elsewhere on this blog: word clouds. There are lots of great text analytics tools in R for this, and the process of making a basic word cloud is very straightforward...

December 14, 2019 |

In this post, we will go through the steps you need to follow if you would like to add a Jekyll / Github Pages blog to R-Bloggers. I recently went through this process and had to search through a lot of information in order to figure out how to do it. ...

### Exploratory Data Analysis of Cell Phone Usage with R: Part 2

December 13, 2019 |

In this post, we will analyze data from my cell phone provider on my phone usage. In this post, we will focus on the volume of my mobile data use across time. We will use exploratory data analysis to understand how my usage of mobile data varies across...

### Accupedo vs. Fitbit Part 2: Convergent Validity of Cumulative Step Counts with R

November 25, 2019 |

This post is a continuation of the previous post on this blog. Last time, we analyzed hourly step count data from the Accupedo app on my phone, and from the Fitbit I wear on my wrist. This time, we will analyze the cumulative step count measurements taken from Accupedo and ...

### Exploratory Data Analysis of Cell Phone Usage with R: Part 1

November 17, 2019 |

In this post, we will analyze data from my cell phone provider on my phone usage. The data contain information on my mobile data use, phone calls, and text messages. We will use exploratory data analysis to understand how my phone usage varies across t...

### Accupedo vs. Fitbit Part 1: Convergent Validity of Hourly Step Counts with R

October 26, 2019 |

In this post, we will investigate the relationship between hourly step count data from two different sources: the Accupedo app on my phone, the Fitbit I wear on my wrist. We will use several visualization and analytical techniques to understand the correspondence (or lack thereof) between the two measurements. Do ...

June 5, 2019 |

In this post, we will see how to download personal Fitbit data histories for step counts, heart rate, and sleep via the Fitbit API. We will use a combination of existing R packages and custom calls to the Fitbit API to get all of the data we are interested in.... [Read more...]

June 5, 2019 |

In this post, we will see how to download personal Fitbit data histories for step counts, heart rate, and sleep via the Fitbit API. We will use a combination of existing R packages and custom calls to the Fitbit API to get all of the data we are interested in.... [Read more...]

June 5, 2019 |

In this post, we will see how to download personal Fitbit data histories for step counts, heart rate, and sleep via the Fitbit API. We will use a combination of existing R packages and custom calls to the Fitbit API to get all of the data we are interested in. ... [Read more...]

### FizzBuzz in R and Python

April 21, 2019 |

In this post, we will solve a simple problem (called "FizzBuzz") that is asked by some employers in data scientist job interviews. The question seeks to ascertain the applicant's familiarity with basic programming concepts. We will see 2 different ways to solve the problem in 2 different statistical programming languages: R and ... [Read more...]

### FizzBuzz in R and Python

April 21, 2019 |

In this post, we will solve a simple problem (called “FizzBuzz”) that is asked by some employers in data scientist job interviews. The question seeks to ascertain the applicant’s familiarity with basic programming concepts. We will see 2 different ways to solve the problem in 2 different statistical programming languages: R ... [Read more...]

### A Tale of Two (Small Belgian) Cities with Open Data: Official Crime Statistics and Self-Reported Feelings of Safety in Leuven and Vilvoorde

February 25, 2019 |

In this post, we will analyze government data from the Flemish region in Belgium on A) official crime statistics and B) self-reported feelings of safety among residents of Flanders. We will focus our analysis on two cities in the province of Flemish Brabant: Leuven and Vilvoorde. A key question of ...

### A Tale of Two (Small Belgian) Cities with Open Data: Official Crime Statistics and Self-Reported Feelings of Safety in Leuven and Vilvoorde

February 25, 2019 |

In this post, we will analyze government data from the Flemish region in Belgium on A) official crime statistics and B) self-reported feelings of safety among residents of Flanders. We will focus our analysis on two cities in the province of Flemish Brabant: Leuven and Vilvoorde. A key question of ...