Question

coach sandoval conducted a study investigating the effectiveness of a new method for teaching a mathematics unit. he recruited 80 students at a college and randomly assigned them to two groups. group 1 was taught with the new method, and group 2 was taught with the traditional method. both groups were taught by the same teacher. at the end of the unit, an achievement test was administered and used to make a comparison of the two groups. what is the response variable in the study? a. the new teaching method d. the score on the achievement test b. the traditional teaching method e. the 80 students c. the teacher in the study

1. an experiment was conducted to assess the effect of baking temperature on the density of bread. a large batch of white bread dough and a large batch of whole wheat bread dough were prepared. each of the batches was formed into 18 loaves, resulting in a total of 36 loaves. each of the white bread loaves was randomly assigned to one of three baking temperatures (low, medium, and high), so that 6 loaves were baked at the low temperature, 6 were baked at the medium temperature, and 6 were baked at the high temperature. a similar process of random assignment was carried out for the whole wheat bread loaves.

which of the following are the treatments in the experiment? a. the 36 loaves of bread d. the baking temperatures (low, medium, high) b. the type of bread (white, whole wheat) e. the two batches of bread dough c. the density of the bread

1. a new laser - guided surgical procedure for removing an inflamed appendix is believed to have a shorter recovery time for patients than an alternative surgical procedure that is not guided by laser has. in an experiment to evaluate recovery time, patients needing the surgery will be randomly assigned to one of two surgical procedures. a surgeon will perform the surgery for one group using lasers and for the other group without the use of lasers. both types of surgeries are performed with similarly sized incisions and patients are unaware of which procedure is performed.

what type of blinding can be accomplished in the experiment? a. both the patient and the surgeon can be blind to the treatment. d. the surgeon can be blind to the treatment, but not the patient. b. neither the patient nor the surgeon can be blind to the treatment. e. blinding is not possible because the design has no control group. c. the patient can be blind to the treatment, but not the surgeon.

Explanation:

1. In the first study, the response variable is what is being measured to see the effect of the teaching - method variable. The score on the achievement test is what is measured to compare the two teaching methods, so it is the response variable.
2. In the bread - baking experiment, treatments are the different levels of the factor being manipulated. Here, the baking temperatures (low, medium, high) are the treatments as they are what is being changed to see the effect on the density of bread.
3. In the surgical experiment, since patients are unaware of which procedure is performed, the patient can be blind to the treatment, but the surgeon performing the surgery knows whether they are using lasers or not, so the surgeon is not blind.

Answer:

1. d. The score on the achievement test
2. d. The baking temperatures (low, medium, high)
3. c. The patient can be blind to the treatment, but not the surgeon.