a study published inThe Journal of Dentistry in2006, for example, a team of dentist recruited 73adult volunteers and randomly split them into groupsthat had one of four substances applied to the gumsjust above the maxillary canine teeth: a clove gel,benzocaine, a placebo resembling the clove gel, or aplacebo resembling benzocaine. Then, after fiveminutes, they compared what happened when thesubjects received two needle sticks in those areas.Not surprisingly, the placebos failed to numb thetissue against the pain, but the clove and benzocaineapplications numbed the tissue equally well.Why was it important to split the volunteersrandomly into the treatment groups rather thanletting them decide which group they wantedto be in?

There are two important reasons for the split of volunteers in random treatment groups rather than…

Answered: In a study published in The Journal of…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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A local jam production company is confident that 60% of the population will like its new grapefruit jelly. (i) If 200 persons taste the new grapefruit jelly, determine the number of persons who are expected to like it. [2](ii) From a random sample of 10 persons who tasted
An experiment was conducted to assess the effect of baking temperature on the density of bread. A large batch ofwhite bread dough and a large batch of whole wheat bread dough were prepared. Each of the batches was formedinto loaves, resulting in a total of loaves. Each of the white bread loaves was randomly assigned to one ofthree baking temperatures (low, medium, and high), so that loaves were baked at the low temperature, werebaked at the medium temperature, and were baked at the high temperature. A similar process of randomassignment was carried out for the whole wheat bread loaves.Which of the following are the treatments in the experiment? (A) The loaves of bread(B) The type of bread (white, whole wheat)(C) The density of the bread(D) The baking temperatures (low, medium, high)(E) The two batches of bread dough
the local survey has reported that 38% of corona cases in 2019 werevresistant to at leat 1 of gthe 3 major antibioticsd used to treat corona.a doctor treated 10 cases of corona in 2019 find the prob that 1 or more out of the 10 were resistant to all the 3 antibiotics .
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A researcher selected a sample of 268 former student-athletes from a list of graduates of a large university. A total of 14% of the sample of athletes had earned graduate degrees as compared to 17% of all graduates. What is the Z obtained value?
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In a public opinion survey, 60 out of a sample of 100 high income voters and 40 out of a sample of 75 low income voters supported a decrease in value added tax VAT. Conclude at the 5% level of significance that the proportion of voters favoring a VAT Degrees difference between high and low income voters. (Where P1 is the proportion of all high income voters who is supported a decrease in VAT, p2 is the same for the low income voters ). The rejection region to test the above hypothesis at the 5% significance level (rounded off to two decimals) is
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