This tutorial explains how to create smooth lines in ggplot2, including several examples.
r - Plot smooth line through all data points - Stack Overflow
Chapter 7 Data Visualization with ggplot
Geom_line
ggplot2: Elegant Graphics for Data Analysis (3e) - 5 Statistical summaries
Analysis in R: Example plots of data format and “ggplot2” package
Be Awesome in ggplot2: A Practical Guide to be Highly Effective - R software and data visualization - Easy Guides - Wiki - STHDA
R code for example in Chapter 17: Regression
how to draw a smooth line connecting all points - tidyverse - Posit Community
Stacked line chart with inline labels – the R Graph Gallery
ggplot2 - How to smooth the line in R ggplot - Stack Overflow
ggplot geom_smooth : r/rstats
How to Plot a Smooth Line using ggplot2 in R ? - GeeksforGeeks
How to Use geom_smooth in R - Sharp Sight
ggplot2 add straight lines to a plot : horizontal, vertical and regression lines - Easy Guides - Wiki - STHDA