pH and enzyme activity

Description

A new enzyme, OOR, makes it possible for a certain bacteria species to develop on oxalate. In an experiment the enzyme activity (micromole per minute per mg) was measured and registered for 29 different pH-values.

Usage

data(OORdata)

Format

A data frame with 29 observations on the following 2 variables.

ph

pH value (a numeric vector)

act

enzyme activity measured in micromole per minute per mg (a numeric vector)

Source

Pierce, E., Becker, D. F., and Ragsdale, S. W. (2010). Identification and characterization of oxalate oxidoreductase, a novel thiamine pyrophosphate- dependent 2-oxoacid oxidoreductase that enables anaerobic growth on oxalate. Journal of Biological Chemistry, 285:40515-40524.

Examples

data(OORdata)

Age and body fat percentage

Description

In order to relate the body fat percentage to age, researchers selected nine healthy adults and determined their body fat percentage.

Usage

data(agefat)

Format

A data frame with 9 observations on the following 2 variables.

age

age of the subject

fatpct

body fat percentage

Source

Ib Skovgaard (2004).Basal Biostatistik 2, Samfundslitteratur.

Examples

data(agefat)

Aids prevalence data

Description

Number of aids cases and deaths for a 19-year period.

Usage

data(aids)

Format

A data frame with 19 observations on the following 3 variables.

year

a numeric vector

cases

a numeric vector

deaths

a numeric vector

Examples

data(aids)

Alligator food preference

Description

Data on food preference for 59 alligators. It is of interest to examine if different sized alligators have different food preferences.

Usage

data(alligator)

Format

A data frame with 59 observations on the following 2 variables.

length

length of the alligator (in meters)

food

a factor with levels Fish Invertebrates Other representing the food preference

Source

Agresti, A. (2007). An Introduction to Categorical Data Analysis. Wiley

Examples

data(alligator)
library(VGAM)
model <- vglm(food ~ length, family=multinomial, data=alligator)
summary(model)

Decomposition of organic material

Description

The amount of organic material in heifer dung was measured after eight weeks of decomposition. The data come from 36 heifers from six treatment groups. The treatments are different types of antibiotics. Only 34 observations are available.

Usage

data(antibio)

Format

A data frame with 34 observations on the following 2 variables.

type

a factor with the antibiotic treatments. Level: Alfacyp Control Enroflox Fenbenda Ivermect Spiramyc

org

a numeric vector with the amount of organic matrial

Source

C. Sommer and B. M. Bibby (2002). The influence of veterinary medicines on the decomposition of dung organic matter in soil. European Journal of Soil Biology", 38, 115-159.

Examples

data(antibio)

Binding of antibiotics

Description

When an antibiotic is injected into the bloodstream, a certain part of it will bind to serum protein. This binding reduces the medical effect. As part of a larger study, the binding rate was measured for 12 cows which were given one of three types of antibiotics: chloramphenicol, erythromycin, and tetracycline

Usage

data(binding)

Format

A data frame with 12 observations on the following 2 variables.

antibiotic

antibiotic type. Factor with levels Chlor Eryth Tetra

binding

binding rate

Source

G. Ziv and F. G. Sulman (1972). Binding of antibiotics to bovine and ovine serum. Antimicrobial Agents and Chemotherapy, 2, 206-213.

Examples

data(binding)

Birth weight of boys and girls

Description

Data from a study that was undertaken to investigate how the sex of the baby and the age of the fetus influence birth weight during the last weeks of the pregnancy.

Usage

data(birthweight)

Format

A data frame with 361 observations on the following 3 variables.

sex

a factor with levels male female

age

a numeric vector

weight

a numeric vector

Source

Anette Dobson (2001). An Introduction to Generalized Linear Models (2nd ed.) Chapman and Hall.

Examples

data(birthweight)
## maybe str(birthweight) ; plot(birthweight) ...

Body fat in women

Description

It is expensive and cumbersome to determine the body fat in humans as it involves immersion of the person in water. This dataset provides information on body fat, triceps skinfold thickness, thigh circumference, and mid-arm circumference for twenty healthy females aged 20 to 34. It is desirable if a model could provide reliable predictions of the amount of body fat, since the measurements needed for the predictor variables are easy to obtain.

Usage

data(bodyfat)

Format

A data frame with 20 observations on the following 4 variables.

Fat

body fat

Triceps

triceps skinfold measurement

Thigh

thigh circumference

Midarm

mid-arm circumference

Source

J. Neter and M.H. Kutner and C.J. Nachtsheim and W. Wasserman (1996). Applied Linear Statistical Models. McGraw-Hill

Examples

data(bodyfat)

Butterfat and dairy cattle

Description

Average butterfat content (percentages) for random samples of 20 cows (10 two year olds and 10 mature (greater than four years old)) from each of five breeds.

Usage

data(butterfat)

Format

A data frame with 100 observations on the following 3 variables.

Butterfat

a numeric vector

Breed

a factor with levels Ayrshire Canadian Guernsey Holstein-Fresian Jersey

Age

a factor with levels 2year Mature

Source

Hand et al. (1993). A Handbook of Small Data Sets. Chapman and Hall

Examples

data(butterfat)

Cabbage yield

Description

Cabbage yield for different treatment methods and different fields

Usage

data(cabbage)

Format

A data frame with 16 observations on the following 3 variables.

method

a factor with levels A C K N

yield

a numeric vector

field

a numeric vector

Examples

data(cabbage)

Tumor size and emission of radioactivity

Description

An experiment involved 21 cancer tumors. For each tumor the weight was registered as well as the emitted radioactivity obtained with a special medical technique (scintigraphic images). Three data points from large tumors were removed.

Usage

data(cancer2)

Format

A data frame with 18 observations on the following 3 variables.

id

tumor id (numeric)

tumorwgt

tumor weight

radioact

emitted radioactivity (numeric)

Source

Shin et al. (2005). Noninvasive imaging for monitoring of viable cencer cells using a dual-imaging reporter gene. The Journal of Nuclear Medicine, 45, 2109-2115.

Examples

data(cancer2)

Hormone concentration in cattle

Description

As part of a larger cattle study, the effect of a particular type of feed on the concentration of a certain hormone was investigated. Nine cows were given the feed for a period, and the hormone concentration was measured initially and at the end of the period.

Usage

data(cattle)

Format

A data frame with 9 observations on the following 3 variables.

cow

cow id

initial

initial homorne concentration (before treatment)

final

final hormone concentration (after treatment)

Examples

data(cattle)

Weight gain for chickens

Description

Twenty chickens were fed with four different feed types - five chickens for each type - and the weight gain was registered for each chicken after a period.

Usage

data(chicken)

Format

A data frame with 20 observations on the following 2 variables.

feed

id of feed type. Numeric but it should be used a factor

gain

Weight gain (numeric)

Source

Anonymous (1949). Query 70. Biometrics, 250–251.

Examples

data(chicken)

Chlorophyll concentration in winter wheat

Description

An experiment with winter wheat was carried in order to investigate if the concentration of nitrogen in the soil can be predicted from the concentration of chlorophyll in the plants. The chlorophyll concentration in the leaves as well as the nitrogen concentration in the soil were measured for 18 plants.

Usage

data(chloro)

Format

A data frame with 18 observations on the following 2 variables.

chloro

chlorophyll concentration in leaves

nit

nitrogen concentration in soil

Source

Experiment was carried out at the Royal Veterinary and Agricultural University in Denmark.

Examples

data(chloro)

Tenderness of pork

Description

Two different cooling methods for pork meat were compared in an experiment with 18 pigs from two different groups: low or high pH content. After slaughter, each pig was split in two and one side was exposed to rapid cooling while the other was put through a cooling tunnel. After the experiment, the tenderness of the meat was measured.

Usage

data(cooling)

Format

A data frame with 18 observations on the following 4 variables.

pig

a numeric vector with the id of the pig

ph

pH concentration level. A factor with levels high low

tunnel

Tenderness observed from tunnel cooling

rapid

Tenderness observed from rapid cooling

References

A. J. Moller and E. Kirkegaard and T. Vestergaard (1987). Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension. Meat Science, 27, p. 275–286.

Examples

data(cooling)
hist(cooling$tunnel[cooling$ph=="low"], main="", 
     xlab="Tenderness (low pH)", col="lightgray", ylim=c(0,5), xlim=c(3,9))
hist(cooling$tunnel[cooling$ph=="high"], main="", 
     xlab="Tenderness (high pH)", col="lightgray", ylim=c(0,5), xlim=c(3,9))

hist(cooling$tunnel[cooling$ph=="low"], freq=FALSE, main="", 
     xlab="Tenderness (low pH)", col="lightgray", ylim=c(0,.5), xlim=c(3,9))
hist(cooling$tunnel[cooling$ph=="high"], freq=FALSE, main="", 
     xlab="Tenderness (high pH)", col="lightgray", ylim=c(0,.5), xlim=c(3,9))

plot(cooling$tunnel, cooling$rapid,
     xlim=c(3,9), ylim=c(3,9),
     xlab="Tenderness (tunnel)", ylab="Tenderness (rapid)")

boxplot(cooling$tunnel, cooling$rapid, names=c("Tunnel", "Rapid"),
        ylab="Tenderness score")

Yield of corn after fertilizer treatment

Description

Two varieties of corn were randomly assigned to the 8 plots in a completely randomized design so that each variety was planted on 4 plots. Four amounts of fertilizer (5, 10, 15, and 20 units) were randomly assigned to the 4 plots in which variety A was planted. Likewise, the same four amounts of fertilizer were randomly assigned to the 4 plots in which variety B was planted. Yield in bushels per acre was recorded for each plot at the end of the experiment.

Usage

data(cornyield)

Format

A data frame with 8 observations on the following 3 variables.

yield

a numeric vector

variety

a factor with levels A B

fertilizer

a numeric vector

Examples

data(cornyield)

Weight of crabs

Description

The length and weight of 361 crabs. The crabs were measured at three different days and they were raised in three different vat types.

Usage

data(crabs)

Format

A data frame with 361 observations on the following 5 variables.

day

id for day of measurement (a numeric vector)

date

date of measurement (a numeric vector)

kar

id of the vat type (a numeric vector

lgth

length of the crab in cm

wgt

weight of the crab in grams

Details

Only crabs from day 1 (190692) are used in the isdals book.

Source

Experiment carried out at the Royal Veterinary and Agricultural University of Copenhagen.

Examples

data(crabs)

Hatching of cuckoo eggs

Description

Cuckoos place their eggs in other birds' nests for hatching and rearing. Researchers investigated 154 cuckoo eggs and measured their size. The adoptive species is also registered (three types). It is believed that cuckoos choose the “adoptive parents” such that the cuckoo eggs are similar in size to the eggs of the adoptive species.

Usage

data(cuckoo)

Format

A data frame with 154 observations on the following 2 variables.

spec

adoptive species. Factor with levels redstart whitethroat wren

width

width of egg (unit: half millimeters)

Source

O.H. Latter (1905). The egg of Cuculus Canorus: An attempt to ascertain from the dimensions of the cuckoo's egg if the species is tending to break up into sub-species, each exhibiting a preference for some one foster-parent. Biometrika, 4, 363-373.

Examples

data(cuckoo)

Disease spread in cucumber

Description

Spread of a disease in cucumbers depends on climate and amount of fertilizer. The amount of infection on standardized plants was recorded after a number of days, and two plants were examined for each combination of climate and dose.

Usage

data(cucumber)

Format

A data frame with 12 observations on the following 3 variables.

disease

a numeric vector

climate

a factor with levels A (change to day temperature 3 hours before sunrise) and B (normal change to day temperature)

dose

a numeric vector with dose of applied fertilizer

Source

de Neergaard, E. et al (1993). Studies of Didymella bryoniae: the influence of nutrition and cultural practices on the occurrence of stem lesions and internal and external fruit rot on different cultivars of cucumber. Netherlands Journal of Plant Pathology. 99:335-343

Examples

data(cucumber)

Running times from relay race

Description

Running times from 5 times 5 km relay race in Copenhagen 2006, held over four days. The sex distribution in the team classifies the teams into six groups. Total running time for a team (not each participant) is registered.

Usage

data(dhl)

Format

A data frame with 24 observations on the following 6 variables.

day

race day. A factor with levels Monday Thursday Tuesday Wednesday

men

number of men on the team (numeric)

women

number of men on the team (numeric)

hours

hours of running (should be combined with minutes and seconds)

minutes

minutes of running (should be combined with hours and seconds)

seconds

seconds of running (should be combined with hours and minutes)

Details

The total running time for the team (not for each participant) is registered. On average, there are 800 teams per combination of race day and sex group. The dataset contains median running times.

Source

http://www.sparta.dk

Examples

data(dhl)
attach(dhl)
totaltime <- 60*60*hours + 60*minutes + seconds ## Total time in seconds

Effect of NaOH treatment of straw on digesitibility

Description

In an experiment with six horses the digestibility coefficient was measured twice for each horse: once after the horse had been fed straw treated with NaOH and once after the horse had been treated ordinary straw.

Usage

data(digestcoefs)

Format

A data frame with 6 observations on the following 3 variables.

horse

horse id

ordinary

digestibility coefficient corresponding to ordinary straw

naoh

digestibility coefficient corresponding to NaOH treated straw

Source

Ib Skovgaard (2004). Basal Biostatistik 2. Samfundslitteratur.

Examples

data(digestcoefs)

dioxin in water

Description

Over a period of 14 years from 1990 to 2003, environmental agencies monitored the average amount of dioxins found in the liver of crabs at two different monitoring stations located some distance apart from a closed paper pulp mill. The outcome is the average total equivalent dose (TEQ), which is a summary measure of different forms of dioxins with different toxicities found in the crabs

Usage

data(dioxin)

Format

A data frame with 28 observations on the following 3 variables.

site

a factor with levels a b corresponding to the two monitoring stations

year

the year

TEQ

a numeric vector for the total equivalent dose

Source

C. J. Schwarz (2013). Sampling, Regression, Experimental Design and Analysis for Environmental Scientists, Biologists, and Resource Managers. Course Notes.

Examples

data(dioxin)
## maybe str(dioxin) ; plot(dioxin) ...

Growth of duckweed

Description

Growth of duckweed (Lemna) by counting the number of leaves every day over a two-week period

Usage

data(duckweed)

Format

A data frame with 14 observations on the following 2 variables.

days

a numeric vector

leaves

a numeric vector

Source

E. Ashby and T. A. Oxley (1935). The interactions of factors in the growth of Lemna. Annals of Botany. 49:309-336

Examples

data(duckweed)

Frequency of signals from electric eels

Description

The investigation of water temperatures influence on the frequency of these electrical signals

Usage

data(eels)

Format

A data frame with 21 observations on the following 2 variables.

temp

the water temperature measured in degrees Celsius

freq

the frequency of of the emitted signal measured in Hz

Source

Data were supplied from the course "Biostatistik, Geostatistik samt Sandsynlighedsteori og Statistik" held at Aarhus University in 2002.

Examples

data(eels)

Optical density for dilutions of a standard dissolution with ubiquitin antibody

Description

As part of a so-called ELISA experiment, the optical density was measured for various dilutions of two different dissolutions with ubiquitin antibody. One dissolution was standard, whereas the other was serum from mice. For each dilution, the mixture proportion describes how many times the original ubiquitin dissolution has been thinned.

Usage

data(elisa)

Format

A data frame with 16 observations on the following 3 variables.

type

type of dissolution. Factor with levels mouse std

mix

a numeric vector describing how many times the original ubiquitin dissolution was thinned

od

optical density

Source

The data was generated by Marianne Freisleben in her work for the master's thesis at the University of Copenhagen.

Examples

data(elisa)

Relation between soil area and price for farms

Description

In February 2010, 12 production farms were for sale in a municipality on Fuen island in Denmark. The dataset contains the soil area in thousands of square meters and the price in thousands of DKK.

Usage

data(farmprice)

Format

A data frame with 12 observations on the following 2 variables.

area

area of soil in thousands of square meters

price

price in thousands of DKK

Examples

data(farmprice)

Forced expiratory volume in children

Description

Dataset to examine if respiratory function in children was influenced by exposure to smoking at home.

Usage

data(fev)

Format

A data frame with 654 observations on the following 5 variables.

Age

age in years

FEV

forced expiratory volume in liters

Ht

height measured in inches

Gender

gender (0=female, 1=male)

Smoke

exposure to smoking (0=no, 1=yes)

Source

I. Tager and S. Weiss and B. Rosner and F. Speizer (1979). Effect of Parental Cigarette Smoking on the Pulmonary Function of Children. American Journal of Epidemiology. 110:15-26

Examples

data(fev)

Gene expression

Description

Two groups were compared in an experiment with six microarrays. Two conditions (the test group and the reference group) were examined on each array and the amount of protein synthesized by the gene (also called the gene expression) was registered.

Usage

data(geneexp)

Format

A data frame with 6 observations on the following 3 variables.

array

array id

test

gene expression level for test group

reference

gene expression level for reference group

Source

Fictious data.

Examples

data(geneexp)

Gestation period for 13 horses

Description

The length of the gestation period (the period from conception to birth) was registered for 13 horses.

Usage

data(gestation)

Format

A data frame with 13 observations on the following variable.

gest

length of gestation period

Source

Fictious (but realistic) data.

Examples

data(gestation)

Sorption of hazardous organic solvents

Description

The sorption was measured for a variety of hazardous organic solvents. The solvents were classified into three types (esters, aromatics, and chloroalkanes), and the purpose was to examine differences between the three types.

Usage

data(hazard)

Format

A data frame with 32 observations on the following 2 variables.

type

type of solvent. Factor with levels aromatic chlor estere

sorption

sorption measurements

Source

J.D. Ortego, T.M Aminabhavi, S.F. Harlapur, R.H. Balundgi (1995). A review of polymeric geosynthetics used in hazardous waste facilities. Journal of Hazardous Materials, 42, 115-156.

Examples

data(hazard)

Nematodes in herring fillets

Description

An experiment was carried out in order to investigate the migration of nematodes in Danish herrings. The fish were allocated to eight different treatment groups corresponding to different combinations of storage time and storage conditions until filleting. After filleting, it was determined whether nematodes were present in the fillet or not.

Usage

data(herring)

Format

A data frame with 884 observations on the following 4 variables.

group

a numeric vector that is the combination of storage and time

time

a numeric vector that contains the duration of storage in hours before the fish is filleted

condi

a numeric vector representing the storage condition

fillet

a numeric vector to indicate the presence of nematodes (1) or absence of nematodes (0)

Details

The variable group is the combination of storage condition and storage time. Notice that a storage time 0 is equivalent to storage condition 0 and that no fish were stored 132 hours under condition 4. Hence, there are only 8 combinations; i.e., 8 levels of the group variable.

Source

A. Roepstorff and H. Karl and B. Bloemsma and H. H. Huss (1993). Catch handling and the possible migration of Anisakis larvae in herring, Clupea harengus. Journal of Food Protection. 56:783-787.

Examples

data(herring)
## maybe str(herring) ; plot(herring) ...

Hormone concentration in cattle

Description

As part of a larger cattle study, the effect of two types of feed on the concentration of a certain hormone was investigated. Twenty cows were given the feed for a period, and the hormone concentration was measured initially and at the end of the period.

Usage

data(hormone)

Format

A data frame with 20 observations on the following 3 variables.

feed

a numeric vector

initial

a numeric vector

final

a numeric vector

Examples

data(hormone)

Enzyme experiment with inhibitors

Description

The data comes from an enzyme experiment with inhibitors. The enzyme acts on a substrate that was tested in six concentrations between 10 micro M and 600 micro M. Three concentrations of the inhibitor were tested, namely 0 (controls), 50 micro M and 100 micro M. There were two replicates for each combination yielding a total of 36 observations of reaction rate.

Usage

data(inhibitor)

Format

A data frame with 36 observations on the following 3 variables.

Iconc

Inhibitor concentration in micro Mole (numeric vector)

Sconc

Substrate concentration in micro Mole (numeric vector)

RR

Reaction rate (numeric vector)

Source

The experiment was carried out by students at a biochemistry course at University of Copenhagen.

Examples

data(inhibitor)

Interspike intervals for neureon from guinea pigs

Description

A study of the membrane potential for neurons from guinea pigs was carried out. The data consists of 312 measurements of interspike intervals; that is, the length of the time period between spontaneous firings from a neuron.

Usage

data(interspike)

Format

A data frame with 312 observations on the following variable.

interval

length of the interspike intervals

Source

Petr Lansky, Pavel Sanda and Jufang He (2006). The parameters of the stochastic leaky integrate-and-fire neuronal model. Journal of Computational Neuroscience, 21, 211-223.

Examples

data(interspike)

Dimensions of jellyfish

Description

Dimensions in millimetres are given of two samples of jellyfish from Hawkesbury River in New South Wales, Australia

Usage

data(jellyfish)

Format

A data frame with 46 observations on the following 3 variables.

Location

a factor with levels Dangar Salamander

Width

the width of the jellyfish in mm

Length

the length of the jellyfish in mm

Source

Hand D.J., Daly F., Lunn A.D., McConway K.J., Ostrowski E. (1993) A Handbook of Small Data Sets. London: Chapman & Hall. Data set 335.

Examples

data(jellyfish)

Lameness scores for horses

Description

A score measuring the symmetry of the gait for eight trotting horses. Each horse was tested twice, namely while it was clinically healthy and after mechanical induction of lameness in a fore limb.

Usage

data(lameness)

Format

A data frame with 8 observations on the following 3 variables.

horse

a numeric vector with an id of the horse

lame

the symmetry score when the horse is lame

healthy

the symmetry score when the horse is healthy

Source

A.T. Jensen, H. Sorensen, M.H. Thomsen and P.H. Andersen (2010). Quantification of symmetry for functional data with application to equine lameness classification. Submitted manuscript.

Examples

data(lameness)

Length of gestation period and lifespan for horses

Description

Length of the gestation period (period from conception to birth) and the lifespan (duration of life) for seven horses.

Usage

data(lifespan)

Format

A data frame with 7 observations on the following 2 variables.

lifespan

duration of life (years)

gestation

length of gestation period (days)

Source

Probably fictitous data.

Examples

data(lifespan)

Listeria growth in experiment with mice

Description

Ten wildtype mice and ten RIP2-deficient mice, i.e., mice without the RIP2 protein, were used in the experiment. Each mouse was infected with listeria, and after three days the bacteria growth was measured in the liver or spleen. Errors were detected for two liver measurements, so the total number of observations is 18.

Usage

data(listeria)

Format

A data frame with 18 observations on the following 3 variables.

organ

a factor with levels liv spl telling where the mesurement was taken

type

a factor with levels rip2 wild corresponding to the mouse type

growth

bacteria growth

Source

Anand, P. K., Tait, S. W. G., Lamkanfi, M., Amer, A. O., Nunez, G., Pagès, G., Pouysségur, J., McGargill, M. A., Green, D. R., and Kanneganti, T.-D. (2011). TLR2 and RIP2 pathways mediate autophagy of listeria monocytogenes via extracellular signal-regulated kinase (ERK) activation. Journal of Biological Chemistry, 286:42981-42991.

Examples

data(listeria)

Compute the logit

Description

Compute the logit of a probability

Usage

logit(p)

Arguments

Value

A number with list with class htest containing the following components:

Author(s)

Claus Ekstrom ekstrom@sund.ku.dk

Fertility of lucerne

Description

Ten plants were used in an experiment of fertility of lucerne Two clusters of flowers were selected from each plant and pollinated. One cluster was bent down, whereas the other was exposed to wind and sun. At the end of the experiment, the average number of seeds per pod was counted for each cluster and the weight of 1000 seeds was registered for each cluster.

Usage

data(lucerne)

Format

A data frame with 10 observations on the following 5 variables.

plant

plant id

seeds.exp

average number of seeds per pod from cluster exposed to sun and wind

wgt.exp

weight of 1000 seeds from cluster exposed to sun and wind

seeds.bent

average number of seeds per pod from cluster that was bent down

wgt.bent

weight of 1000 seeds from cluster that was bent down

Source

H.L. Petersen (1954). Pollination and seed setting in lucerne. Kgl. Veterinaer og Landbohojskole, Aarsskrift 1954, 138-169.

Examples

data(lucerne)

Nematodes in mackerel

Description

Data to examine if cooling right after catching prevents nematodes (roundworms) from moving from the belly of mackerel to the fillet. A total of 150 mackerels were investigated and their length, number of nematodes in the belly, and time before counting the nematodes in the fillet were registered. The response variable is binary: presence or absence of nematodes in the fillet.

Usage

data(mackerel)

Format

A data frame with 150 observations on the following 7 variables.

length

a numeric vector

visc

a numeric vector

left

a numeric vector

right

a numeric vector

filet

a numeric vector

portion

a numeric vector

time

a numeric vector

Source

A. Roepstorff and H. Karl and B. Bloemsma and H. H. Huss (1993). Catch handling and the possible migration of Anisakis larvae in herring, Clupea harengus. Journal of Food Protection. 56:783-787.

Examples

data(mackerel)
## maybe str(mackerel) ; plot(mackerel) ...

Parasite counts for children with malaria

Description

A medical researcher took blood samples from 31 children who were infected with malaria and determined for each child the number of malaria parasites in 1 ml of blood.

Usage

data(malaria)

Format

A data frame with 31 observations on the following variable.

parasites

the number of malaria parasites

Source

M.L. Samuels and J.A. Witmer (2003). Statistics for the Life Sciences (3rd ed.). Pearson Education, Inc., New Jersey.

References

C. B. Williams (1964) Patterns in the Balance of Nature. Academic Press, London.

Examples

data(malaria)

Comparison of mass spectrometry methods

Description

Two common methods are GC-MS (gas chromatography-mass spectrometry) and HPLC (high performance liquid chromatography). The biggest difference between the two methods is that one uses gas while the other uses liquid. We wish to determine if the two methods measure the same amount of muconic acid in human urine.

Usage

data(massspec)

Format

A data frame with 16 observations on the following 3 variables.

sample

a numeric vector

hplc

a numeric vector

gcms

a numeric vector

Examples

data(massspec)

Weight of packs with minced meat

Description

In meat production, packs of minced meat are specified to contain 500 grams of minced meat. A sample of ten packs was drawn at random and the weights (in grams) of the content was recorded.

Usage

data(mincedmeat)

Format

A data frame with 10 observations on the following variable.

wgt

weight of minced meat in grams

Source

Fictitious data.

Examples

data(mincedmeat)

Utilization of vitamin A

Description

In an experiment on the utilization of vitamin A, 20 rats were given vitamin A over a period of three days. Ten rats were fed vitamin A in corn oil and ten rats were fed vitamin A in castor oil (American oil). On the fourth day, the liver of each rat was examined and the vitamin A concentration in the liver was determined.

Usage

data(oilvit)

Format

A data frame with 20 observations on the following 2 variables.

type

type of oil. A factor with levels am corn

avit

vitamin A concentration in liver

Source

C.I.Bliss (1967). Statistics in Biology. McGraw-Hill, New York

Examples

data(oilvit)

Tensile strength of Kraft paper

Description

Tensile strength in pound-force per square inch of Kraft paper (used in brown paper bags) for various amounts of hardwood contents in the paper pulp.

Usage

data(paperstr)

Format

A data frame with 19 observations on the following 2 variables.

hardwood

hardwood content

strength

tensile strength in pound-force per square inch

Source

G. Joglekar and J. H. Schuenemeyer and V. LaRiccia (1989). Lack-of-Fit Testing When Replicates Are Not Available. The American Statistician. 43:135-143

Examples

data(paperstr)

Phosphor concentration in plants during growth

Description

In a plant physiological experiment the amount of water-soluble phosphorous (among others) was measured in the plants, as a percentage of dry matter. The phosphorous concentration was measured nine weeks during the growth season, and the averages over the plants in the experiments was reported.

Usage

data(phosphor)

Format

A data frame with 9 observations on the following 2 variables.

week

week number

phos

phosphor concentration (average over the plants)

Source

Ib Skovgaard (2004). Basal Biostatistik 2, Samfundslitteratur.

Examples

data(phosphor)

Picolram and herbacide efficacy

Description

A small dataset for evaluating the effects of increasing pplication rates of picloram for control of tall larkspur.

Usage

data(picloram)

Format

A data frame with 313 observations on the following 3 variables.

replicate

a factor with levels 1 2 3 corresponding to the three replicates (locations) used

dose

the dose of picloram used in kg ae/ha

status

a numeric vector. 0 means the plant survived, 1 that it died

Source

David L. Turner, Michael H. Ralphs and John O. Evans (1992): Logistic Analysis for Monitoring and Assessing Herbicide Efficacy. Weed Technology

Examples

data(picloram)

Effect of stimuli on pillbugs

Description

An experiment on the effect of different stimuli was carried out with 60 pillbugs. The bugs were split into three groups: 20 bugs were exposed to strong light, 20 bugs were exposed to moisture, and 20 bugs were used as controls. For each bug it was registered how many seconds it used to move six inches.

Usage

data(pillbug)

Format

A data frame with 60 observations on the following 2 variables.

time

number of seconds it took the pillbug to move six inches

group

treatment. A factor with levels Control Light Moisture

Source

Samuels and Witmer (2003). Statistics for the Life Sciences (3rd ed.). Pearson Education, Inc., New Jersey.

Examples

data(pillbug)

Height and diameter of pines

Description

The data consist of height and diameter (in breast height) measurements from 18 pine trees.

Usage

data(pine)

Format

A data frame with 18 observations on the following 2 variables.

diam

diameter of the pine tree

height

height of the pine tree

Source

J.N.R. Jeffers (1959). Experimental Design and Analysis in Forest Research. Almqvist and Wiksell, Stockholm.

Examples

data(pine)

Effects of insecticides on mortality

Description

The data concerns three insecticides (rotenone, deguelin, and a mixture of those). A total of 818 insects were exposed to different doses of one of the three insecticides. After exposure, it was recorded if the insect died or not.

Usage

data(poison)

Format

A data frame with 818 observations on the following 3 variables.

status

status of insect: dead=1, alive=0 (numeric vector)

poison

type of insecticide. A factor with levels D (deguelin) M (mixture)) R (rotenone)

logdose

natural logarithm of dose of insecticide

Source

D.J. Finney (1952). Probit analysis. Cambridge University Press, England.

Examples

data(poison)

Pork colour over time

Description

Investigation of meat quality of pork through color stability of pork chops. The color was measured from a pork chop from each of ten pigs at days 1, 4, and 6 after storage.

Usage

data(pork)

Format

A data frame with 30 observations on the following 3 variables.

brightness

a numeric vector

day

a numeric vector

pig

a numeric vector

Examples

data(pork)

Enzyme experiment

Description

In an experiment with the enzyme puromycin, the rate of the reaction, V, was measured twice for each of six concentrations C of the substrate.

Usage

data(puromycin)

Format

A data frame with 12 observations on the following 2 variables.

conc

concentration of the substrate (numeric vector)

rate

rate of reaction (numeric vector)

Source

Unknown

Examples

data(puromycin)

Drugs in rat's livers

Description

An experiment was undertaken to investigate the amount of drug present in the liver of a rat. Nineteen rats were randomly selected, weighed, placed under a light anesthetic, and given an oral dose of the drug. It was believed that large livers would absorb more of a given dose than a small liver, so the actual dose given was approximately determined as 40 mg of the drug per kilogram of body weight. After a fixed length of time, each rat was sacrificed, the liver weighed, and the percent dose in the liver was determined.

Usage

data(ratliver)

Format

A data frame with 19 observations on the following 4 variables.

BodyWt

body weight of each rat in grams

LiverWt

weight of liver in grams

Dose

relative dose of the drug given to each rat as a fraction of the largest dose

DoseInLiver

proportion of the dose in the liver

Source

S. Weisberg (1985). Applied Linear Regression (2nd ed.). John Wiley and Sons

Examples

data(ratliver)

Weight gain of rats

Description

Data contains the weight gain for rats fed on four different diets: combinations of protein source (beef or cereal) and protein amount (low and high)

Usage

data(ratweight)

Format

A data frame with 40 observations on the following 3 variables.

Gain

a numeric vector

Protein

a factor with levels Beef Cereal

Amount

a factor with levels High Low

Source

Hand et al. (1993). A Handbook of Small Data Sets. Chapman and Hall

Examples

data(ratweight)

Plots a standardaized residual

Description

Plots a standardized residual plot from an lm object and provides additional graphics to help evaluate the variance homogeneity and mean.

Usage

residualplot(object, bandwidth = 0.3, ...)

Arguments

Details

Plots a standardized residual plot from an lm object and provides additional graphics to help evaluate the variance homogeneity and mean.

The brown area is a smoothed estimate of 1.96*SD of the standardized residuals in a window around the predicted value. The brown area should largely be rectangular if the standardized residuals have more or less the same variance.

The dashed line shows the smoothed mean of the standardized residuals and should generally follow the horizontal line through (0,0).

Value

Produces a standardized residual plot

Author(s)

Claus Ekstrøm <ekstrom@sund.ku.dk>

Examples

# Linear regression example
x <- rnorm(100)
y <- rnorm(100, mean=.5*x)
model <- lm(y ~ x)
residualplot(model)

Weight increase for cattle fed with rice straw

Description

Weight gain of cattle fed with rice straw to see if rice straw can replace wheat straw as potential feed for slaughter cattle in Tanzania

Usage

data(ricestraw)

Format

A data frame with 35 observations on the following 2 variables.

time

number of days that the calf has been fed rice straw

weight

weight gain (in kg) since the calf was first fed rice straw

Source

Ph.D. project at the Faculty of LIFE Sciences, University of Copenhagen

Examples

data(ricestraw)
plot(ricestraw$time, ricestraw$weight)
lm(weight ~ time, data=ricestraw)

Emission of greenhouse gas

Description

In order to study emission of greenhouse gasses in forests, 14 paired values of water content in the soil and emission of N2O were collected.

Usage

data(riis)

Format

A data frame with 14 observations on the following 2 variables.

water

content of water in soil, measured as a volume percentage (numeric vector)

N2O

emission of N2O, measured as micrograms per square metre per hour (numeric vector)

Source

Jesper Riis Christiansen, Department of Geosciences and Natural Resource Management, University of Copenhagen.

Examples

data(riis)

Effect of ferulic acid on ryegrass growth

Description

24 perennial ryegrass plants have been treated with different concentrations of ferulic acid, and the length of the root has been measured after a period of time

Usage

data(ryegrass)

Format

A data frame with 24 observations on the following 2 variables.

conc

concentration of ferulic acid in mM (numeric vector)

rootl

length of root in cm (numeric vector)

Source

Inderjit, Streibig, J. C., and Olofsdotter, M. (2002). Joint action of phenolic acid mixtures and its significance in allelopathy research. Physiologia Plantarum, 114:422-428.

Examples

data(ryegrass)

Parasite counts for salmons

Description

An experiment with two difference salmon stocks, from River Conon in Scotland and from River Atran in Sweden, was carried out. Thirteen fish from each stock were infected and after four weeks the number of a certain type of parasites was counted for each of the 26 fish.

Usage

data(salmon)

Format

A data frame with 26 observations on the following 2 variables.

stock

origin of the fish. A factor with levels atran conon

parasites

a numeric vector with the parasite counts

Source

Heinecke, R. D, Martinussen, T. and Buchmann, K. (2007). Microhabitat selection of Gyrodactylus salaris Malmberg on different salmonids. Journal of Fish Diseases, 30, 733-743.

Examples

data(salmon)

Sarcomere length and meat tenderness

Description

The average sarcomere length in the meat and the corresponding tenderness as scored by a panel of sensory judges was examined. A high score corresponds to tender meat.

Usage

data(sarcomere)

Format

A data frame with 24 observations on the following 3 variables.

pig

factor with levels 1–24. Pid id

sarc.length

numeric Sarcomere length

tenderness

numeric Meat tenderness score

References

A. J. Moller and E. Kirkegaard and T. Vestergaard (1987). Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension. Meat Science, 27, p. 275–286.

Examples

data(sarcomere)
cor(sarcomere$sarc.length, sarcomere$tenderness)

Size of seal population from 1952 to 1962

Description

The number of seals in a population were counted each year during a period of 11 years, freom 1952 to 1962.

Usage

data(seal)

Format

A data frame with 11 observations on the following 2 variables.

year

year of seal count

size

number of seals in population

Source

J. Verzani (1005). Using R for Introductory Statistics. Chapman & Hall/CRC, London

Examples

data(seal)

Quality of soap

Description

The electric conductance was measured for 32 pieces of soap in 4 groups (8 pieces in each group). The content of fatty acid differs between the groups. Quality of soap is mainly determined by its content of fatty acid, which can be determined with a chemical analysis. It is much easier to measure the electric conductance, and it is therefore of interest if there is a simple relation between the two.

Usage

data(soap)

Format

A data frame with 32 observations on the following 3 variables.

group

the groups of soap (notice: numeric vector, not factor)

fattyacid

content if fatty acid in percent (numeric vector)

conduct

electric conductance in milli Siemens (numeric vector)

Source

Unknown

Examples

data(soap)

Stress and growth for soybeans

Description

An experiment was carried out with 26 soybean plants. The plants were pairwise genetically identical, so there were 13 pairs in total. For each pair, one of the plants was 'stressed' by being shaken daily, whereas the other plant was not shaken. After a period the plants were harvested and the total leaf area was measured for each plant.

Usage

data(soybean)

Format

A data frame with 13 observations on the following 3 variables.

pair

id of the pair of plants

stress

Total leaf area of stressed plant

nostress

total leaf area of control plant

Examples

data(soybean)

Digestibility percentage of fat for various levels of stearic acid

Description

The average digestibility percent was measured for nine different levels of stearic acid proportion

Usage

data(stearicacid)

Format

A data frame with 9 observations on the following 2 variables.

stearic.acid

Percentage of stearic acid

digest

Average digestibility percentage

Source

Jorgensen, G. and Hansen, N.G. (1973). Fedtsyresammensaetningens indflydelse paa fedstoffers fordojelighed. Landokonomisk Forsogslaboratorium.

Examples

data(stearicacid)
lm(digest ~ stearic.acid, data=stearicacid)

Stomach experiment

Description

Fifteen subjects participated in an experiment related to overweight and got a standardized meal.The interest was, among others, to find relationships between the time it takes from a meal until the stomach is empty again and the concentration of a certain hormone.

Usage

data(stomach)

Format

A data frame with 15 observations on the following 2 variables.

conc

hormone concentration

empty

time from meal until the stomach is empty

Source

Ib Skovgaard (2004). Basal Biostatistik 2. Samfundslitteratur.

Examples

data(stomach)

Tartar for dogs

Description

A dog experiment was carried out in order to examine the effect of two treatments on the development of tartar. Apart from the two treatment groups there was also a control group. Twenty-six dogs were used and allocated to one of the three groups. After four weeks each dog was examined, and the development of tartar was summarized by an index.

Usage

data(tartar)

Format

A data frame with 26 observations on the following 2 variables.

treat

treatment. A factor with levels Control HMP P2O7

index

a numeric vector with the tartar index

Examples

data(tartar)

Growth of lettuce plants treated with herbicide

Description

68 lettuce plants were treated with the herbicide tetraneurin-A in different concentrations. After 5 days each plant was harvested and the root length in cm was registered.

Usage

data("tetra")

Format

A data frame with 68 observations on the following 2 variables.

konz

concentration of herbicide (numeric vector)

root

root length in cm (numeric vector)

Source

Belz, R., Cedergreen, N., and Sørensen, H. (2008). Hormesis in mixtures - Can it be predicted. Science of the Total Environment, 404:77-87.

Examples

data(tetra)

Throwing thumbtacks

Description

A brass thumbtack was thrown 100 times and it was registered whether the pin was pointing up or down towards the table upon landing.

Usage

data(thumbtack)

Format

The format is: int [1:100] 1 1 0 0 1 1 0 1 0 0 ...

Details

1 corresponds to "tip pointing down" and 0 corresponds to "tip pointing up"

References

Mats Rudemo (1979). Statistik og sandsynlighedslaere med biologiske anvendelser. Del 1: Grundbegreber.

Examples

data(thumbtack)
mean(thumbtack)

Clutch size of turtles

Description

Data to examine the effect of turtle carapace length on the clutch size of turtles.

Usage

data(turtles)

Format

A data frame with 18 observations on the following 2 variables.

length

a numeric vector

clutch

a numeric vector

Source

K. G. Ashton and R. L. Burke and J. N. Layne (2007). Geographic variation in body and clutch size of gopher tortoises. Copeia. 49:355-363.

Examples

data(turtles)
## maybe str(turtles) ; plot(turtles) ...

Feline urinary tract disease

Description

The impact of food intake and exercise as possible explanatory variables for the urinary tract disease in cats.

Usage

data(urinary)

Format

A data frame with 74 observations on the following 3 variables.

disease

a factor with levels no yes

food

a factor with levels excessive normal

exercise

a factor with levels little much

Source

Willeberg P (1976). Interaction effects of epidemiologic factors in the feline urological syndrome. Nordisk Veterinaer Medicin, 28, 193-200

Examples

data(urinary)
head(urinary)

Food intake for Danish people 1985

Description

The daily food intake was studied for 2224 subjects, and the content of many different vitamins and substances were meaured,

Usage

data(vitamina)

Format

A data frame with 2224 observations on the following 20 variables.

person

subject id (a numeric vector)

wt

weight (kg)

ht

height (cm)

sex

sex: 1 for male, 2= for female

age

age

bmr

basal metabolic rate

E_bmr

energy divided by bmr

energi

energy content (kJ)

Avit

vitamin A (RE)

retinol

retinol (microgram)

betacar

beta-caroten (microgram)

Dvit

vitamin D (microgram

Evit

vitamin E (alphaTE)

B1vit

vitamin B1 (milligram)

B2vit

vitamin B2 (milligram)

niacin

niacin (NE)

B6vit

vitamin B6 (milligram)

folacin

folacin (microgram)

B12vit

vitamin B12 (microgram)

Cvit

vitamin C (milliggram)

Details

Only variables Avit and bmr are used in the "Introduction to Statistical Data Analysis for the Life Sciences" book.

Source

J. Haraldsdottir, J.H. Jensen, A. Moller (1985). Danskernes kostvaner 1985, Hovedresultater. Levnedsmiddelstyrelsen, publikation nr. 138.

Examples

data(vitamina)