LAPOP Time-Series Graphs

This function creates time series graphs using LAPOP formatting. If there are waves missing at the beginning or end of the series, the function will omit those waves from the graph (i.e., the x-axis will range from the earliest wave for which data is supplied to the latest). If there are waves missing in the middle of the series, those waves will be displayed on the x-axis, but no data will be shown.

Usage

lapop_ts(
  data,
  outcome_var = data$prop,
  lower_bound = data$lb,
  upper_bound = data$ub,
  wave_var = as.character(data$wave),
  label_var = data$proplabel,
  point_var = data$prop,
  ymin = 0,
  ymax = 100,
  main_title = "",
  source_info = "LAPOP",
  subtitle = "",
  lang = "en",
  color_scheme = "#A43D6A",
  percentages = TRUE,
  label_vjust = -2.1,
  max_years = 15,
  label_angle = 0
)

Arguments

data

Data Frame. Dataset to be used for analysis. The data frame should have columns titled wave (survey wave/year; character vector), prop (outcome variable; numeric), proplabel (text of outcome variable; character); lb (lower bound of estimate; numeric), and ub (upper bound of estimate; numeric). Default: None (must be supplied).

wave_var, outcome_var, label_var, lower_bound, upper_bound, point_var

Character, numeric, character, numeric, numeric, character. Each component of the data to be plotted can be manually specified in case the default columns in the data frame should not be used (if, for example, the values for a given variable were altered and stored in a new column).

ymin, ymax

Numeric. Minimum and maximum values for y-axis. Default: 0, 100.

main_title

Character. Title of graph. Default: None.

source_info

Character. Information on dataset used (country, years, version, etc.), which is added to the bottom-left corner of the graph. Default: LAPOP ("Source: LAPOP Lab" will be printed).

subtitle

Character. Describes the values/data shown in the graph, e.g., "Percent of Mexicans who agree...". Default: None.

lang

Character. Changes default subtitle text and source info to either Spanish or English. Will not translate input text, such as main title or variable labels. #' Takes either "en" (English) or "es" (Spanish). Default: "en".

color_scheme

Character. Color of lines and dots. Takes hex number, beginning with "#". Default: "#A43D6A" (red).

percentages

Logical. Is the outcome variable a percentage? Set to FALSE if you are using means of the raw values, so that the y-axis adjusts accordingly. Default: TRUE.

label_vjust

Numeric. Customize vertical space between points and their labels. Default: -2.1.

max_years

Numeric. Threshold for automatic x-axis label rotation. When the number of unique country labels exceeds this value, labels will be smaller and if necessary rotated for better readability. Default: 15 years.

label_angle

Numeric. Angle (in degrees) to rotate x-axis labels when max_years is exceeded. Default: 0.

Value

Returns an object of class ggplot, a ggplot line graph showing values of a variable over time.

Details

The input data must have a specific format to produce a graph. It must include columns for the survey wave (wave), the outcome variable (prop), the lower bound of the estimate (lb), the upper bound of the estimate (ub), and a string for the outcome variable label (proplabel).

Author

Luke Plutowski, luke.plutowski@vanderbilt.edu && Robert Vidigal, robert.vidigal@vanderbilt.edu

Examples

if (FALSE) df <- data.frame(wave = c("2008", "2010", "2016/17", "2018/19", "2021"),
prop = c(23.2, 14.4, 35.8, 36.6, 40),
proplabel = c("23.2%", "14.4%", "35.8%", "36.6%", "40.0%"),
lb = c(20.2, 11.9, 33.3, 33.1, 38),
ub = c(26.2, 16.9, 38.3, 40.1, 42)
)

lapop_ts(df,
 main_title = "Ecuadorians are becoming more interested in politics",
 subtitle = "% politically interested",
 source_info = "Ecuador 2006-2021",
 ymin = 0,
 ymax = 55
 ) # \dontrun{}
#> Error in data$wave: object of type 'closure' is not subsettable