9.6 Lab: From wide to long and back

Let’s start with wide-format…

x <- data.frame(unit = c("Peter", "Paul", "Pedro"),
                trust.2006 = c(1,5,6),  
                trust.2007 = c(1,5,6),
                Victimization.2006 = c(0,0,1),
                Victimization.2007 = c(1,1,0))

Table 9.3: Wide format

unit	trust.2006	trust.2007	Victimization.2006	Victimization.2007
Peter	1	1	0	1
Paul	5	5	0	1
Pedro	6	6	1	0

Convert it to long-format…

x <- x %>% pivot_longer(-unit, names_to = "variable", values_to = "value") %>%
      separate(col = "variable", into = c("variable", "time"), sep = "\\.") %>% 
      pivot_wider(names_from = variable, values_from = value) 

Table 9.4: Long format

unit	time	trust	Victimization
Peter	2006	1	0
Peter	2007	1	1
Paul	2006	5	0
Paul	2007	5	1
Pedro	2006	6	1
Pedro	2007	6	0

Convert it back to wide-format…

  x <- x %>% gather(key = variable,
                    value = values,
                    -unit,
                    -time) %>% 
              unite(variable_time, variable, time, sep = ".") %>%
              spread(key = variable_time, value = values)

Table 9.5: Wide format

unit	trust.2006	trust.2007	Victimization.2006	Victimization.2007
Paul	5	5	0	1
Pedro	6	6	1	0
Peter	1	1	0	1