Question

2. (3 pts) What technique for gathering data (observation, experiment, or census) do you think was used in each of the following studies? No explanation needed.

a) The Colorado Division of Wildlife netted and released 774 fish at Quincy Reservoir. There were 219 perch, 315 bull gill, 83 pike and 157 rainbow trout.

The technique used is census.

b) A study of all league football scores attained through touchdowns and field goals was conducted by the National Football League to determine whether field goals account for more scoring events than touchdowns.

The technique used is observation.

c) A veterinarian wants to test a strain of antibiotic on calves to determine their resistance to common infection. In a pasture are 22 newborn calves. However, blood tests to determine resistance to infection can be done on all calves.

Answer 1

a) Census

Note : A census is a type of gathering data , where the entire population is surveyed . Data is recorded on each and every individual element of the population.Data can be in the form of kind , length, weight etc.  Here all the fishes in the reservoir are netted and each fish is observed and species is recorded. Thus, it is census.

b) Census

Note : As all league football scores are studied , the entire population of league football is studied. Data recorded is scores through touchdowns and field goals of each and every league football , this is census.

c) Experiment

Note : In experimental studies , the researcher manipulates the subject under study and observes the effect of independent variable on the dependent variable. Here the subject under study is calves. The researcher wants to see the effect of antibiotics(independent variable) on resistance to common infection( dependent variable). The researcher randomly administers antibiotics on some calves and compares the resistance to common infection on those  the the antibiotics are administered with those it was not .