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Plot time series and rolling correlation over time by group

Source: R/plot_functions.R
plot_corr.Rd

Produces a faceted line plot showing the primary series (x_var), secondary series (y_var), and rolling correlation (roll_corr) over time, with one facet per group. Horizontal reference lines are drawn at y = -1 (dashed), 0 (solid), and 1 (dashed). Optionally adds a shaded confidence ribbon around x_var. If dat contains a column named roll_corr (e.g. from rolling_corr) it will be included in the plot; if absent the line is simply omitted.

Usage

plot_corr(
  dat,
  date_var,
  grp_var,
  x_var,
  y_var,
  x_var_lower = NULL,
  x_var_upper = NULL,
  facet_labels = NULL,
  legend_labels = NULL,
  y_max = NULL,
  col_values = c(brewer.pal(8, "RdPu")[8], brewer.pal(8, "Greens")[5], brewer.pal(8,
    "Blues")[8])
)

Arguments

dat

A data frame containing the two time series, a roll_corr column, a date column, and a grouping column.

date_var

Character string giving the name of the date column (class Date).

grp_var

Character string giving the name of the grouping column used for faceting.

x_var

Character string giving the name of the primary time series column.

y_var

Character string giving the name of the secondary time series column.

x_var_lower

Character string giving the name of the column containing the lower confidence bound for x_var. If NULL (default), no ribbon is drawn. Both x_var_lower and x_var_upper must be supplied to draw a ribbon.

x_var_upper

Character string giving the name of the column containing the upper confidence bound for x_var. If NULL (default), no ribbon is drawn.

facet_labels

Named character vector of display labels for the facets, passed to as_labeller. Names must match values in the grouping column. If NULL (default), raw group values are shown.

legend_labels

Character vector of length 3 giving legend labels for roll_corr, x_var, and y_var respectively. If NULL (default), the internal metric names (roll_corr, x_var, y_var) are shown in the legend.

y_max

Numeric. Maximum value for the y-axis. If supplied, the axis is set to [-1, y_max] and confidence bounds are clamped to this value. Default is NULL (auto-scaled).

col_values

Character vector of length 3 specifying line colours for roll_corr, x_var, and y_var respectively. Defaults to dark purple, mid-green, and dark blue from RColorBrewer palettes.

Value

A ggplot object.

See also

rolling_corr to compute roll_corr; plot_lag to visualise the lag distribution.

Examples

if (FALSE) { # \dontrun{
plot_corr(
  dat           = data_corr,
  date_var      = "date_end",
  grp_var       = "province",
  x_var         = "r_mean",
  y_var         = "movement",
  x_var_lower   = "r_q2.5",
  x_var_upper   = "r_q97.5",
  legend_labels = c("Rolling correlation", "Rt", "Mobility")
)
} # }