Question

(i)   identify the variable(s) in the study, (ii) for each vari- able tell the type of variable (e.g., categorical and ordinal, discrete, etc.), (iii) identify the observational unit (the thing sampled), and (iv) determine the sample size.

2.

a)     A physician measured the height and weight of each of 37 children.

(b)     During a blood drive, a blood bank offered to check the cholesterol of anyone who donated blood. A total of 129 persons donated blood. For each of them, the blood type and cholesterol levels were recorded.

3.

(a)     A biologist measured the number of leaves on each of 25 plants.

(b)     A physician recorded the number of seizures that each of 20 patients with severe epilepsy had during an eight-week period.

Answer 1

2.a)     A physician measured the height and weight of each of 37 children.

(b)     During a blood drive, a blood bank offered to check the cholesterol of anyone who donated blood. A total of 129 persons donated blood. For each of them, the blood type and cholesterol levels were recorded.

Answer:

i) The variable of study is Height and Weight

(ii) The variable height and weight continuous variable type also both the variables are Quantative and as they have a value 0 as origin so they both are Ratio variable.

(iii) Observational units is a single child

(iv) Here clearly the sample size is 37

(b)

(i)The variable of study is Blood type and cholesterol levels.

(ii) Blood type can be A, B, AB, O. So it is  Categorical nominal variable

On the other hand cholesterol levels can be measured numerically and it has a origin 0 point which means no cholesterol. SO this variable is Quantative Ratio variable

(iii) Observational units is a single blood doner.

(iv) sample size is 129

3.(a) A biologist measured the number of leaves on each of 25 plants.

(b) A physician recorded the number of seizures that each of 20 patients with severe epilepsy had during an eight-week period.

Answer: (i) Variable is number of leaves

(ii) This is discrete variable type as it is countable.

(iii) Observation unit is plant.

(IV) sample size is 25

(b)

(i) Variable is number of seizure.

(ii) Variable type is : discrete as it is countable.

(iii) Observational unit: patients with severe epilepsy

(iv) Sample size is 20