PlackettLuce (version 0.4.3)

beans: Preferred Bean Varieties in Nicaragua

Description

This is a subset of data from trials of bean varieties (Phaseolus vulgaris L.) in Nicaragua over five growing seasons. Farmers were asked to try three varieties of bean from a total of ten varieties and to rank them in order of preference. In addition, for each variety the farmers were asked to compare each trial variety to the local variety and state whether they considered it to be better or worse.

Usage

beans

Format

A data frame with 842 records and 14 variables:

variety_a

The name of variety A in the comparison.

variety_b

The name of variety B in the comparison.

variety_c

The name of variety C in the comparison.

best

The variety the farmer ranked in first place ("A", "B" or "C").

worst

The variety the farmer ranked in last place ("A", "B" or "C").

var_a

How the farmer ranked variety A compared to the local variety ("Worse" or "Better").

var_b

How the farmer ranked variety B compared to the local variety ("Worse" or "Better").

var_c

How the farmer ranked variety C compared to the local variety ("Worse" or "Better").

season

A factor specifying the growing season ("Po - 15", "Ap - 15", "Pr - 16", "Po - 16", "Ap - 16".

year

The year of planting.

maxTN

The maximum temperature at night during the vegetative cycle (degrees Celsius).

lon

The geographic coordinate longitude (X axis) for where the plot was established.

lat

The geographic coordinate latitude (Y axis) for where the plot was established.

planting_date

A Date, specifying the start date of planting the trial.

Details

There are three crop seasons in Central America:

Primera

May - August.

Postrera

September - October.

Apante

November - January.

Beans can be planted near the beginning of each season, though are most commonly planted in the Postrera or Apante seasons.

Examples

# Consider the best and worst rankings. These give the variety the
# farmer thought was best or worst, coded as A, B or C for the
# first, second or third variety assigned to the farmer
# respectively.
data(beans)
head(beans[c("best", "worst")], 2)

# Fill in the missing item
beans$middle <- complete(beans[c("best", "worst")],
                         items = c("A", "B", "C"))
head(beans[c("best", "middle", "worst")], 2)

# This gives an ordering of the three varieties the farmer was
# given. The names of these varieties are stored in separate
# columns
varieties <- beans[c("variety_a", "variety_b", "variety_c")]
head(varieties, 2)

# Use these names to decode the orderings of order 3
order3 <- decode(beans[c("best", "middle", "worst")],
                 items = beans[c("variety_a", "variety_b", "variety_c")],
                 code = c("A", "B", "C"))

# Now consider the paired comparisons agains the local variety
head(beans[c("var_a", "var_b", "var_c")], 2)

# Convert these results to a vector and get the corresponding trial variety
outcome <- unlist(beans[c("var_a", "var_b", "var_c")])
trial_variety <- unlist(beans[c("variety_a", "variety_b", "variety_c")])

# Create a data frame of the implied orderings of order 2
order2 <- data.frame(Winner = ifelse(outcome == "Worse",
                                     "Local", trial_variety),
                     Loser = ifelse(outcome == "Worse",
                                    trial_variety, "Local"),
                     stringsAsFactors = FALSE, row.names = NULL)
head(order2, 2)

# Finally combine the rankings of order 2 and order 3
R <- rbind(as.rankings(order3, input = "orderings"),
           as.rankings(order2, input = "orderings"))
head(R)
tail(R)