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Times to loss of equilibrium of 120 juvenile salmonids held at three constant temperatures, simulated from a known model so that what a fitted model estimates can be set against the values the data were made from. Twelve trials of ten fish, four at each temperature (23, 25 and 27 degrees C), were checked every hour for five days, so each failure is known to have happened between two checks. Fish that had not failed by the end of the fifth day are survivors. The coolest temperature is one a summer heat wave can reach, so that the assay informs predictions for the field (see stream_record).

Usage

static_assay

Format

A tibble with 120 rows, one per fish, and 7 columns:

id

Integer, the fish.

trial

Character, the trial the fish was in ("S01" to "S12").

path_id

Character, the temperature group ("T23", "T25", "T27"), the key to its temperature trajectory.

temp

Numeric, the constant temperature of the trial, degrees C.

mass

Numeric, body mass, g.

event

Integer, 1 if the fish lost equilibrium, 0 if it survived to the end of the trial.

t_upper

Numeric, the time of the check at which the fish was found to have failed, or of the last check for a survivor, minutes.

Source

Simulated by data-raw/make-example-data.R in the package's repository.

Details

The data are simulated, not measured. The values are plausible for a juvenile rainbow trout acclimated to 14 degrees C, and stand for no particular study. The model they come from is described under ramp_assay, which shares it, and is stored with the data as attr(static_assay, "truth").

Examples

head(static_assay)
#> # A tibble: 6 × 7
#>      id trial path_id  temp  mass event t_upper
#>   <int> <chr> <chr>   <dbl> <dbl> <int>   <dbl>
#> 1     1 S01   T23        23  19.9     0    7200
#> 2     2 S01   T23        23  14.3     0    7200
#> 3     3 S01   T23        23   8       0    7200
#> 4     4 S01   T23        23  16.6     1    2040
#> 5     5 S01   T23        23  29.5     1    2400
#> 6     6 S01   T23        23   9       1    5820

# The temperature trajectory of each group, and the checks.
path <- data.frame(path_id = rep(c("T23", "T25", "T27"), each = 2),
                   time = rep(c(0, 7200), 3),
                   temp = rep(c(23, 25, 27), each = 2))
checks <- expand.grid(path_id = c("T23", "T25", "T27"),
                      time = seq(0, 7200, by = 60))
long <- build_hazard_data(static_assay, path, "interval",
                          covariates = c("mass", "trial"), checks = checks)
head(long)
#> # A tibble: 6 × 12
#>      id  mass trial path_id   tau exposure    Ta failed    Tr log_tau tau_ref
#>   <int> <dbl> <chr> <chr>   <dbl>    <dbl> <dbl>  <int> <dbl>   <dbl>   <dbl>
#> 1     1  19.9 S01   T23        30       60    23      0    25    3.40     360
#> 2     1  19.9 S01   T23        90       60    23      0    25    4.50     360
#> 3     1  19.9 S01   T23       150       60    23      0    25    5.01     360
#> 4     1  19.9 S01   T23       210       60    23      0    25    5.35     360
#> 5     1  19.9 S01   T23       270       60    23      0    25    5.60     360
#> 6     1  19.9 S01   T23       330       60    23      0    25    5.80     360
#> # ℹ 1 more variable: log_exposure <dbl>