Question

a. Distinguish between description and inference as reasons for using statistics.

b. Suppose you have data for a population, such as obtained in a census. Explain why descriptive statistics are helpful, but inferential statistics are not needed.

a. Which statement below best distinguishes description from inference?

A. Statistical inference provides useful summaries of the data, while description helps make predictions and decide whether observed patterns are meaningful.

B. Statistical inference provides useful summaries of data for a sample, while description provides useful summaries of data for a population.

C. Statistical description provides useful summaries of data for a sample, while inference provides useful summaries of data for a population.

D. Statistical description provides useful summaries of the data, while inference helps make predictions and decide whether observed patterns are meaningful.

b. Why are descriptive statistics helpful, but inferential statistics not needed?

A. Descriptive statistics can help make predictions about the population, but the amount of data in the inferential statistics is too large to be helpful.

B. Descriptive statistics can summarize large amount of raw data, but since everything is known for the population, there is nothing to infer.

C. Descriptive statistics can summarize the large amount of raw data, but the amount of data in the inferential statistics is too large to be helpful.

D. Descriptive statistics can help make predictions about the population, so there is nothing to infer.

Answer 1

a)

D. The statistical description provides useful summaries of the data, while inference helps make predictions and decide whether observed patterns are meaningful.

For sampled data, we use descriptive statistics to summarize the data, but mainly inferential statistics helps us to bring insights from the data which cannot be easily determined using sampling.

b)

B. Descriptive statistics can summarize a large amount of raw data, but since everything is known for the population, there is nothing to infer.

Since all the data is captured in a census survey, we don't have to use inferential statistics in order to predict future. Thus it is not much useful

Answer 2

For a) it is D. For b) it is B