1) Problem #PRAJWY9 "PRAJWY9 - 257268 - This data is from..." |
A)
The data collected reflects the respiratory status of patients recruited for a randomised clinical multicenter trial. In each of two centres, eligible patients were randomly assigned to treatment or placebo. During the treatment, the respiratory status (categorised as poor or good ) was determined at each of four, monthly visits. The trial recruited 111 participants (54 in the treatment group, 57 in the placebo group).The data below is a two table that represents the effect of treatment on respiratory status on the fourth and last monthly visit. Does the data support the claim that the treatment type results in a difference in respiratory status after 4 months? Which of the following tests would be most appropriate? © STATS4STEM.ORG |
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B)
Define the null and alternative hypothesis. A) Ho: There is no association between respiratory status and treatment Ha: There is an association between respiratory status and treatment B) Ho: There is an association between respiratory status and treatment Ha: There is no association between respiratory status and treatment C) p represents the proportion of the population that have a respiratory status rated as good. Ho: Pplacebo = ptreatment Ha: The proportions differ D) p represents the proportion of the population that have a respiratory status rated as good. Ho: Pplacebo = ptreatment Ha: Pplacebo < ptreatment |
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C)
Refer the two way table, what is the expected count when the observed is 32? Round answer to the nearest hundredth. |
D)
Refer the two way table, what is the expected count when the observed is 34? Round answer to the nearest hundredth. |
E)
What condition or conditions need to be checked before proceeding with the hypothesis test? Click all that apply. |
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F)
Are all conditions met? |
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G)
What is the degrees of freedom for this problem? |
H)
What is the chi-squared test statistic? Round answer to the nearest hundredth. |
I)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth.
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J)
Assume that the significance level is 0.05, the best conclusion would be: A) Reject the null hypothesis. B) I calculated a p-value of 0.04, which is less than the stated significance level of 0.05. Therefore, we reject the null hypothesis. The data supports the claim that the proportion of individuals that have a respiratory status of "good" differs between the placebo and treatment populations. C) I calculated a p-value of 0.04, which is less than the stated significance level of 0.05. Therefore, we can reject the null hypothesis. D) I calculated a p-value of 0.04, which is less than the stated significance level of 0.05. Therefore, we fail to reject the null hypothesis. The data supports the claim that the proportion of individuals that have a respiratory status of "good" differs between the placebo and treatment populations. E) I calculated a p-value of 0.04, which is less than the stated significance level of 0.05. Therefore, we fail to reject the null hypothesis. The data does not support the claim that the proportion of individuals that have a respiratory status of "good" differs between the placebo and treatment populations. F) I calculated a p-value of 0.04, which is less than the stated significance level of 0.05. Therefore, we fail to reject the null hypothesis. |
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2) Problem #PRAJNC8 "PRAJNC8 - Calculate p value for t-dist" |
A)
Instructions on how use technology to calculate the p-value for the t-distribution. You will have to use either the TI-83 or R/Rweb to complete these Assistment questions as you will need to calculate the exact p-value. Knowing how to use the t-table will not be good enough to finish this Assistment. EXAMPLE #1 For df=8 and t=-2: TI-83 Instructions: To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -2, 8) = 0.0403 ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-2, 8) = 0.0403 ### P(X<t) = pt(t, df) Here is a shaded density curve that represents the above calculation: EXAMPLE #2 If df=18 and t=2.3: TI-83 Instructions: To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(2.3, 10, 18) = 0.0168 ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: P(X>2.3) = 1 - P(X<2.3) = 1-pt(2.3, 18) = 0.0168 ### P(X<t) = pt(t, df) Here is a shaded density curve that represents the above calculation: Calculate the p-value for a df=23, and t = -2.43. Round answer to the nearest hundredth. © STATS4STEM.ORG |
B)
Calculate the p-value for a df=18, and t=1.14. Round answer to the nearest hundredth. |
C)
Calculate the p-value for a df=27, and t=0.64. Round answer to the nearest hundredth.
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D)
Calculate the p-value for a df=14, and t = -1.28. Round answer to the nearest hundredth. |
3) Problem #PRAJGXW "PRAJGXW - Hyp Test #10" |
In a hypothesis test, which of the following will cause a decrease in β, the probability of making a type II error? © STATS4STEM.ORG |
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4) Problem #PRAJU6V "PRAJU6V - 255520 - The parameter of ..." |
A)
The parameter of a population is 85. Which of the following sampling distributions are biased? Select all that apply. © STATS4STEM.ORG |
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B)
Which sampling distribution is the best estimator of the statistic? |
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5) Problem #PRAEVP5 "PRAEVP5 - 136860 - About 70% of Face..." |
A)
About 70% of Facebook users are outside the United States. If 100 users are randomly surveyed, find the probability that: a) At least 75 are from outside the United States. Do not use the normal approximation to the binomial for these problems (or your answers may not match) and round this and subsequent answers to the nearest hundredth. © STATS4STEM.ORG |
B)
b) Exactly 71 are from outside of the United States. Round to nearest hundred. |
C)
c) At most 80 live outside of the United States. |
D)
d) Less than 64 live outside of the United States. |
E)
e) Less than 65 or more than 72 live outside of the United States. |
6) Problem #PRAJ9EW "PRAJ9EW - 267301 - A simulation was ..." |
A)
A simulation was run that created 1000 linear regression lines drawn using 1000 random samples of size 10 drawn from a population of interest. The results of the analysis can be seen in the graphics below: Write a short synopsis of what you believe the three graphs represent. Make sure to note the difference between the 1 black line and the numerous red lines. In addition, how do you think the 2nd and 3rd graphs are related to the first? Make sure to use the following words in your answer: sample, population, alpha, beta © STATS4STEM.ORG |
B)
From the graphics, one can tell that: |
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C)
It is clear from the second and third graphs that a and b are ___________________ estimators of alpha and beta. |
7) Problem #PRAJBPP "PRAJBPP - 239673 - The test scores f..." |
The test scores for an AP Statistics class have the distribution N(85, 5). How high would a student need to score to be in the top twenty percent? Link to z-table. *** Round answer to the nearest whole number. *** © STATS4STEM.ORG |
8) Problem #PRAJGYJ "PRAJGYJ - 244753 - Twenty-one elasti..." |
Twenty-one elastic bands were divided into two groups.One of the sets was placed in hot water (60-65 degrees C) for four minutes, while the other was left at ambient temperature. After a wait of about ten minutes, the amounts of stretch, under a 1.35 kg weight, were recorded. Which of the following statements are correct? Check all that apply. © STATS4STEM.ORG |
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9) Problem #PRAKCGD "PRAKCGD - 270230 - If log(x) = 1, ca..." |
A)
If log(x) = 1, calculate x. © STATS4STEM.ORG |
B)
If log(y) = 2.5, calculate y. Round answer to the nearest hundredth. |
C)
If log(y) = 3.3, calculate y. Round answer to the nearest hundredth. |