Question

question #5
what kind of experiment is shown in the picture?

completely randomized design
randomized block design
simple random sample
matched pairs

question #6
the transportation department of a large city wants to estimate the proportion of residents who would use a system of aerial gondolas to commute to work. the gondolas would be part of the citys effort to relieve traffic congestion. the department asked a random sample of residents whether they would use the gondolas. the residents could respond with yes, no, or maybe. which of the following is the best description of the method for data collection used by the department?

a census
a sample survey
an experiment with a completely randomized design
an experiment with a matched - pairs design

Explanation:

Question #5

In a completely randomized design, subjects are randomly assigned to treatment groups. Here, students are randomly assigned to Group 1 (Treatment A: no - practice exam) and Group 2 (Treatment B: practice exam). There are no blocks (as in randomized block design) where subjects are first divided into homogeneous blocks, no matching of pairs (as in matched pairs), and it is an experiment (not just a simple random sample which is a sampling method for surveys).

A census involves collecting data from every member of the population. Here, a random sample of residents is asked (not the whole population), so it's not a census. An experiment involves manipulating a variable (treatment). In this case, the department is just asking a question (no treatment manipulation). A sample survey is a method of collecting data from a sample of the population (which is what is done here: a random sample of residents is asked if they would use the gondolas).

Answer:

Completely Randomized Design

Question #6