Mix 10 TUTORiAL
In this EQ guide and complete tutorial, you will learn the 4 key approaches to using equalization when mixing music, in addition to 10 essential tips I have picked up after over 12 years of mixing.
Mix 10 TUTORiAL
Mixed-effects models are a powerful tool for modeling fixed and random effects simultaneously, but do not offer a feasible analytic solution for estimating the probability that a test correctly rejects the null hypothesis. Being able to estimate this probability, however, is critical for sample size planning, as power is closely linked to the reliability and replicability of empirical findings. A flexible and very intuitive alternative to analytic power solutions are simulation-based power analyses. Although various tools for conducting simulation-based power analyses for mixed-effects models are available, there is lack of guidance on how to appropriately use them. In this tutorial, we discuss how to estimate power for mixed-effects models in different use cases: first, how to use models that were fit on available (e.g. published) data to determine sample size; second, how to determine the number of stimuli required for sufficient power; and finally, how to conduct sample size planning without available data. Our examples cover both linear and generalized linear models and we provide code and resources for performing simulation-based power analyses on openly accessible data sets. The present work therefore helps researchers to navigate sound research design when using mixed-effects models, by summarizing resources, collating available knowledge, providing solutions and tools, and applying them to real-world problems in sample sizing planning when sophisticated analysis procedures like mixed-effects models are outlined as inferential procedures.
In this tutorial, we will consider different scenarios for a simulation-based power analysis and provide examples on how to perform such an analysis. This paper is designed to meet the needs of researchers who have some experience with mixed-effects modeling, and thus does not discuss topics such as model selection or optimal random-effects structure (Barr, Levy, Scheepers, & Tily, 2013; Bates, Kliegl, Vasishth, & Baayen, 2015a). Consequently, all scenarios introduced in this tutorial assume that an optimal model has already been selected. Thus, our aim is to provide tools and resources for researchers to use and explore simulation-based procedures, empowering them to find solutions for their own specific use cases. To achieve this, we use real-world data sets, rather than simplified examples, hoping that these examples would cover a wide problem space.
Generally, and with some amount of experience, it is possible to implement simulations from scratch. However, several premade software packages are available to simplify and speed up this process (e.g. simglm (LeBeau, 2019), pamm (Martin, 2012), powerlmm (Magnusson, 2018)). In this tutorial, we will focus on the two complementary packages mixedpower (Kumle, Võ, & Draschkow, 2018) and simr (Green & MacLeod, 2016), as they allow for power simulations for a wide range of (G)LMMs with different fixed- and random-effect structures.
There are various ways to conduct a power analysis for mixed models, with Westfall et al. (2014) and Brysbaert and Stevens (2018) constituting important introductory works in this domain. Here, we focus on the two packages simr (Green & MacLeod, 2016) and mixedpower (Kumle et al., 2018), which cover a wide range of possible use cases, and we encourage a complementary use of these tools (for a comparison of the two packages see Supplementary Notebook). Through parallel computing, mixedpower provides an efficient solution tailored to common scenarios in experimental and cognitive psychology, where complex models and designs with crossed random effects are prevalent. Mixedpower allows researchers to estimate, with relative efficiency, the power of fixed effects for different levels of random effects and thus can aid in decisions regarding sample size planning. Trading speed and efficiency against a wider range of use cases (e.g. setting up models from scratch, computing confidence intervals for power estimates), simr allows for more customizable simulations and therefore enables the user to exert more control over the simulation process; for instance, specifying the statistical test used to determine significance during the simulation process. However, we wish to acknowledge that additional useful software packages for simulation-based solutions to mixed models exist (e.g. simglm (LeBeau, 2019), pamm (Martin, 2012), powerlmm (Magnusson, 2018), sim.glmm (Johnson et al., 2015)), and that the resources introduced in this tutorial do not cover all available resources for power estimation in (G)LMMs.
Considering power while planning experimental designs is important for the reliability and replicability of findings. To this end, a range of experimental parameters (e.g. sample size, number of stimuli/items) need to be justified and set accordingly for achieving adequately powered studies. However, power analyses are not necessarily a trivial task and may pose a feasibility barrier to researchers, especially when more sophisticated analyses like (G)LMMs are outlined for a study. In this tutorial paper, we provide code and resources to assist in the simulation-based computation of power, which should empower researchers not only to plan high-powered confirmatory studies but also to meet preregistration and submission requirements. We hope the tools and resources collated here will foster further exploration of simulation-based power analysis in (G)LMMs.
Explore excerpts from the extraordinary autobiography Narrative of the Life of Frederick Douglass, as you examine the author's purpose for writing and his use of the problem and solution text structure. By the end of this tutorial, you should be able to explain how Douglass uses the problem and solution text structure in these excerpts to convey his purpose for writing.
Read George Vest's "Eulogy of the Dog" speech in this two-part interactive tutorial. In this series, you'll identify and examine Vest's use of ethos, pathos, and logos in his speech. In Part One, you'll identify Vest's use of logos in the first part of his speech. In Part Two, you'll identify his use of ethos and pathos throughout his speech.
Study excerpts from the classic American novel Little Women by Louisa May Alcott in this interactive English Language Arts tutorial. Using excerpts from chapter eight of Little Women, you'll identify key characters and their actions. You'll also explain how interactions between characters contributes to the development of the plot.
Analyze how O. Henry uses details to address the topics of value, sacrifice, and love in his famous short story, "The Gift of the Magi." In this interactive tutorial, you'll also determine two universal themes of the story.
Read more from the fantasy novel The Princess and the Goblin by George MacDonald in Part Two of this three-part series. By the end of this tutorial, you should be able to compare and contrast the archetypes of two characters in the novel.
This interactive tutorial is Part One in a two-part series. By the end of Part Two, you should be able to explain how the narrator changes through her interaction with the setting. Click below to launch Part Two.
Explore excerpts from Ralph Waldo Emerson's essay "Self-Reliance" in this two-part series. This tutorial is Part Two. In this tutorial, you will continue to examine excerpts from Emerson's essay that focus on the topic of traveling. You'll examine word meanings and determine the connotations of specific words. You will also analyze the impact of specific word choices on the meaning of this portion of the essay.
Explore excerpts from Ralph Waldo Emerson's essay "Self-Reliance" in this two-part interactive tutorial series. You will examine word meanings, examine subtle differences between words with similar meanings, and think about the emotions or associations that are connected to specific words. Finally, you will analyze the impact of specific word choices on the meaning of these excerpts.
Explore excerpts from Ralph Waldo Emerson's essay "Self-Reliance" in this interactive two-part tutorial. This tutorial is Part Two. In this two-part series, you will learn to enhance your experience of Emerson's essay by analyzing his use of the word "genius." You will analyze Emerson's figurative meaning of "genius" and how he develops and refines the meaning of this word over the course of the essay.
Practice analyzing word choices in "The Raven" by Edgar Allan Poe, including word meanings, subtle differences between words with similar meanings, and emotions connected to specific words. In this interactive tutorial, you will also analyze the impact of specific word choices on the meaning of the poem.
Practice analyzing word choices in "The Raven" by Edgar Allan Poe in this interactive tutorial. In this tutorial, you will examine word meanings, examine subtle differences between words with similar meanings, and think about emotions connected to specific words. You will also analyze the impact of specific word choices on the meaning of the poem.
Learn how to create a Poem in 2 Voices in this interactive tutorial. This tutorial is Part Three of a three-part series. In this tutorial, you will learn how to create a Poem in 2 Voices using evidence drawn from a literary text: The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson.
Learn how authors create mood in a story through this interactive tutorial. You'll read a science fiction short story by author Ray Bradbury and analyze how he uses images, sound, dialogue, setting, and characters' actions to create different moods. This tutorial is Part One in a two-part series. In Part Two, you'll use Bradbury's story to help you create a Found Poem that conveys multiple moods.