Question

Identify each of the following studies as using either descriptive statistics or inferential statistics.

a) Calculating the relative frequency of Toyota cars passing by your house between 7pm and 8pm this evening.

b) Estimating the proportion of households in Fiji that have at least two dependents, from a random sample of 100 Fijian households.

c) Measuring the fuel efficiency of five brand new Holden Commodore SV6 cars in order to find out whether the average fuel consumption of this make and model is better than 10L/100km.

d) Calculating the proportion of female students in an economic statistics class.

e) Estimating the average age of students at USP from a sample of 200 randomly selected students.

Answer 1

a) Descriptive statistics.

Reason: Here we are calculating the relative frequency, no no estimation or inference is drawn about any parameters.

b) Inferential statistics.

Reason: Here we are estimating the proportion which is a part of inferential statistics.

c) Descriptive statistics.

Here we are taking measure which can be used in future for drawing inference.

d) Descriptive statistics.

Reason: here we are only calculating the proportion. No estimation or inference is drawn.

e) Inferential statistics.

Reason: Here we are estimating the average age of students, Which is a part of inference.