
Concept explainers
Medical Marijuana? An international poll of physicians was conducted on the New England Journal of Medicine website asking “Do you believe that the overall medicinal benefits of marijuana outweigh the risks and potential harms?” Identify the
- a. specified attribute.
- b. population.
- c. population proportion.
- d. Of the 1446 physicians who responded, 76% said yes. Is the proportion 0.76 (76%) a sample proportion or a population proportion? Explain your answer.
a.

Identify the specified attribute.
Explanation of Solution
Given info:
In a poll conducted on the physicians which askedabout“Do you believe that the overall medicinal benefits of marijuana out-weigh the risks and potential harms”.
Justification:
From the information, it is observed that the study is about the medicinal benefits of marijuana. Therefore, the feeling that the overall medicinal benefits of marijuana out-weigh the risks and potential harms is considered as specified attribute.
b.

Identify the population.
Answer to Problem 1RP
The population is all international physicians.
Explanation of Solution
Justification:
Population:
Population consists of the complete subjects that are included in the study for making inferences.
From the information, it is observed that the study is about the medicinal benefits of marijuana of all international physicians. Therefore, all international physiciansis considered as population.
c.

Identify the population proportion.
Explanation of Solution
Justification:
Population proportion:
The proportion that is calculated from the population which has a specific attribute is termed as the population proportion.
From the information, it is observed that the study is about the medicinal benefits of marijuana of all international physicians.
Therefore, the population proportion is proportion of international physicians in the sample who are feeling that the overall medicinal benefits of marijuana outweigh the risks and potential harms.
d.

Check whether the proportion 0.76 is a sample proportion or a population proportion.
Answer to Problem 1RP
The proportion represents sample proportion.
Explanation of Solution
Justification:
Population proportion:
The proportion that is calculated from the population which has a specific attribute is termed as the population proportion.
Sample proportion:
The fraction of number of members sampled which have a specified attribute and the sample size n aretermed as the sample proportion.
Here, 76% out of 1,446 physicians said yes. Hence,the proportion 0.76 is for the sample of 1,446 physicians. Therefore,it represents sample proportion.
The overall international physicians would be more than 1,446.
Want to see more full solutions like this?
Chapter 12 Solutions
Introductory Statistics (10th Edition)
- Please help me with the following question on statisticsFor question (e), the drop down options are: (From this data/The census/From this population of data), one can infer that the mean/average octane rating is (less than/equal to/greater than) __. (use one decimal in your answer).arrow_forwardHelp me on the following question on statisticsarrow_forward3. [15] The joint PDF of RVS X and Y is given by fx.x(x,y) = { x) = { c(x + { c(x+y³), 0, 0≤x≤ 1,0≤ y ≤1 otherwise where c is a constant. (a) Find the value of c. (b) Find P(0 ≤ X ≤,arrow_forwardNeed help pleasearrow_forward7. [10] Suppose that Xi, i = 1,..., 5, are independent normal random variables, where X1, X2 and X3 have the same distribution N(1, 2) and X4 and X5 have the same distribution N(-1, 1). Let (a) Find V(X5 - X3). 1 = √(x1 + x2) — — (Xx3 + x4 + X5). (b) Find the distribution of Y. (c) Find Cov(X2 - X1, Y). -arrow_forward1. [10] Suppose that X ~N(-2, 4). Let Y = 3X-1. (a) Find the distribution of Y. Show your work. (b) Find P(-8< Y < 15) by using the CDF, (2), of the standard normal distribu- tion. (c) Find the 0.05th right-tail percentage point (i.e., the 0.95th quantile) of the distri- bution of Y.arrow_forward6. [10] Let X, Y and Z be random variables. Suppose that E(X) = E(Y) = 1, E(Z) = 2, V(X) = 1, V(Y) = V(Z) = 4, Cov(X,Y) = -1, Cov(X, Z) = 0.5, and Cov(Y, Z) = -2. 2 (a) Find V(XY+2Z). (b) Find Cov(-x+2Y+Z, -Y-2Z).arrow_forward1. [10] Suppose that X ~N(-2, 4). Let Y = 3X-1. (a) Find the distribution of Y. Show your work. (b) Find P(-8< Y < 15) by using the CDF, (2), of the standard normal distribu- tion. (c) Find the 0.05th right-tail percentage point (i.e., the 0.95th quantile) of the distri- bution of Y.arrow_forward== 4. [10] Let X be a RV. Suppose that E[X(X-1)] = 3 and E(X) = 2. (a) Find E[(4-2X)²]. (b) Find V(-3x+1).arrow_forward2. [15] Let X and Y be two discrete RVs whose joint PMF is given by the following table: y Px,y(x, y) -1 1 3 0 0.1 0.04 0.02 I 2 0.08 0.2 0.06 4 0.06 0.14 0.30 (a) Find P(X ≥ 2, Y < 1). (b) Find P(X ≤Y - 1). (c) Find the marginal PMFs of X and Y. (d) Are X and Y independent? Explain (e) Find E(XY) and Cov(X, Y).arrow_forward32. Consider a normally distributed population with mean μ = 80 and standard deviation σ = 14. a. Construct the centerline and the upper and lower control limits for the chart if samples of size 5 are used. b. Repeat the analysis with samples of size 10. 2080 101 c. Discuss the effect of the sample size on the control limits.arrow_forwardConsider the following hypothesis test. The following results are for two independent samples taken from the two populations. Sample 1 Sample 2 n 1 = 80 n 2 = 70 x 1 = 104 x 2 = 106 σ 1 = 8.4 σ 2 = 7.6 What is the value of the test statistic? If required enter negative values as negative numbers (to 2 decimals). What is the p-value (to 4 decimals)? Use z-table. With = .05, what is your hypothesis testing conclusion?arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGALGlencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt



