Today I am going to continue highlighting resources I found helpful when studying for my prelims (which I successfully passed!). The last post on this topic was about blocking trials, and I'm glad I reviewed blocking and randomization for my exam since it was helpful in answering two of the questions on my exam. The… Continue reading Two ANOVA Tutorials

# Tag: statistics

## Blocking Field Trials and the First Law of Geography

I'm studying for my prelims this semester, which involves going back over the classes I've taken over the last 4 years, reviewing my research proposal, and just generally refreshing my memory about the topics a person with a PhD in agronomy should know. I'm focusing on traditional statistics and experimental designs this week, which reminded… Continue reading Blocking Field Trials and the First Law of Geography

## Making Box Plots

Last month I posted about how to read box plots, and today I'm sharing how you can make your own. I picked two online tools that don't require you to calculate the mean and quartiles yourself and shared a quick couple lines of code for the R users out there. Let's start with Desmos! Desmos… Continue reading Making Box Plots

## Box and Whisker Plots

Box and whisker plots are one of my favorite ways to visualize data, but they can be challenging to read if you haven't seen them before. Today I'm going to show a couple examples, and in the future I'll show you how to make your own! Firstly, box and whisker plots are also called boxplots.… Continue reading Box and Whisker Plots

## Vocab Word: Multicollinearity

I'm going to continue highlighting words I get asked about regularly. Today's feature: multicollinearity! This is a word you've probably heard about in stats class, but might not know specifically what it is or why it matters. We worry about multicollinearity when we are using multiple independent variables to model one output. One of your… Continue reading Vocab Word: Multicollinearity

## Data Downloads: 2017 Ag Census

The 2017 Census of Agriculture results will be released on Thursday, April 11th. If you're looking for updated production information, this is a great resource. Here are some quick facts about the census and some ways to see the results! What is the Census of Agriculture? It's a record of all the humans, animals, and… Continue reading Data Downloads: 2017 Ag Census

## Averaging Plot Data in Excel

Back in January I shared my favorite way to average plot data in R, but some of my lab mates don't use R and are looking for an alternative. They keep averaging their plot data by highlighting 10 cells at a time and using the AVERAGE function, which is rather inefficient and introduces human error.… Continue reading Averaging Plot Data in Excel

## Averaging Plot Data in R

In agronomy research, its very common to collect 10 plants from a single plot, take measurements on them, and average those measurements. The plot average is the value we run statistics on, whether that means building a regression or running an ANOVA. I've recently seen a lot of my fellow grad students averaging measurements by… Continue reading Averaging Plot Data in R

## Random Forest

Machine learning algorithms are cool because the can handle continuous and categorical variables and have few assumptions about data distribution. As the name machine learning would imply, it's a highly automated process. Sometimes they take a while to compute, but the computer can be unsupervised during that time. One machine learning algorithm I use in… Continue reading Random Forest

## Basic Statistics Fact Sheet

This might be an older fact sheet (originally published in 2008), but it's still an incredibly helpful guide: Highlighted Fact Sheet I like it for a few reasons. Firstly, it's written in plain English. There's not a single equation in it, and the whole paper is only 3 pages. Secondly, and probably more importantly, it… Continue reading Basic Statistics Fact Sheet