4 FAQ

Here are some commonly asked questions.

Installation

I get the error: package is not available for my current R version

This might be because you have an unstable internet connection. Either try again when there are less people using the internet connection, use a different connection, or contact one of the maintainers for alternative offline options.

I installed without errors---but cannot see the templates

You will need to restart your R session. You can do this by clicking on "Session" in the menu up top and then choosing "Restart R". Alternatively, you can use a keyboard shortcut: CTRL+SHIFT+F10

If this does not work, try restarting your computer and opening R-Studio again.

If this they still do not appear, then please take a look at this GitHub post.

I am unsure if I have the MRAN or CRAN version of R installed.

If you click tools > global options... Then under the general tab you can see the R version. If you click on change... then the different versions will pop up. MRAN will be in a microsoft folder whereas CRAN will be in an R folder. See this picture for an example.

Data analysis / Coding

Basic introductory course

http://swcarpentry.github.io/r-novice-gapminder/

I have a date column and a time column, how do I combine the two?

You can use paste() to combine the columns and lubridate::ymd_hm() to convert them into a datetime. For example, here's how you would combine the columns date_of_x and time_of_y (this assumes that the dates are formatted like yyyy-mm-dd and the times are formatted like hh:mm) in the data frame my_data

library(dplyr)
library(lubridate)
my_data %>%
  mutate(date_time = ymd_hm(paste(date_of_x, time_of_y), tz = "UTC")

My summary table is wrong. There are missing values where there should be none.

This may be because you need to specify na.rm = TRUE, which indicates that missing values should be discarded before calculation:

sum(c(1:10, NA))
## [1] NA
sum(c(1:10, NA), na.rm = TRUE)
## [1] 55

How do I prevent results from my exploratory analysis from showing up in the word document

You can add include = FALSE in the chunk header:

```{r, echo = FALSE, include = FALSE, warnings = FALSE, messages = FALSE}

# summary code here

```

Searching for commas is driving me nuts!

Turn on code diagnostics, it will show up with helpful messages https://support.rstudio.com/hc/en-us/articles/205753617-Code-Diagnostics

General statistical methodologies

I am not sure what statistical test to use

Take a look at this table from the UCLA statistics department https://stats.idre.ucla.edu/other/mult-pkg/whatstat/

I am not sure what plot to use for visualising my data

Take a look at this book https://serialmentor.com/dataviz/

https://www.data-to-viz.com

Need some more background info on survey methods

LSHTM epidemiology in crises material: http://conflict.lshtm.ac.uk/page_02.htm WHO nutritional survey standards: https://www.who.int/nutrition/publications/anthropometry-data-quality-report/en/