Stat Unit Quiz 10
Hint: Refer to slide 6 of Tuesday lecture 2. A hypothesis test for a population proportion ρ is given below:Ho: ρ = 0.10 Ha: ρ ≠ 0.10 If the sample size n = 500 and sample proportion ρ-hat = 0.04, then the z-statistic is:
(0.04 - 0.10)/√[( 0.10 *(1 - 0.10))/ 500]
Hint: Refer to slide 6 of Tuesday lecture 2. A hypothesis test for a population proportion ρ is given below:Ho: ρ = 0.10 Ha: ρ ≠ 0.10 If the sample size n = 100 and sample proportion ρ-hat = 0.15, then the z-statistic is:
(0.15 - 0.10)/√[( 0.10 *(1 - 0.10))/ 100] The z-statistic is found by (ρ-hat - ρ)/√[(ρ*(1-ρ))/n]
A hypothesis test for a population proportion ρ is given below:Ho: ρ = 0.40 Ha: ρ > 0.40 Use Standard Normal Table to calculate the p-value for this hypothesis test for z-statistic = 0.50. The p-value is:
0.3085
A hypothesis test for a population proportion ρ is given below:Ho: ρ = 0.70 Ha: ρ ≠ 0.70 Use Standard Normal Table to calculate the p-value for this hypothesis test for z-statistic = 0.50. The p-value is:
0.6170
A hypothesis test for a population proportion ρ is given below:Ho: ρ = 0.40 Ha: ρ > 0.40 Use Standard Normal Table to calculate the p-value for this hypothesis test for z-statistic = -1.50. The p-value is:
0.9332
A null hypothesis is that the probability is 0.7 that a new drug will provide relief in a randomly selected patient. The alternative is that the probability of relief is greater than 0.7. Suppose the treatment is used on 500 patients and there are 380 successes. How would a p-value be calculated in this situation? Hint: Refer to slide 18 of Tuesday lecture 1.
Find the chance of 380 or more successes, calculated assuming the true success rate is 0.7.
About 90% of the general population is right-handed. A researcher speculates that artists are less likely to be right-handed than the general population. In a random sample of 100 artists, 83 are right-handed. Which of the following best describes the p-value for this situation? Hint: Refer to slide 18 of Tuesday lecture 1.
The probability the sample proportion would be as small as 0.83, or even smaller, if the population proportion of artists who are right-handed is actually 0.90.
A hypothesis test is done in which the alternative hypothesis states that more than 10% of a population is left-handed. The p-value for the test is calculated to be 0.25. Which statement is correct?
We cannot conclude that more than 10% of the population is left-handed.
Determine if the following statement is a typical null hypothesis (Ho) or alternative hypothesis (Ha): The graduation rate for all division I athletes is not equal to the 85% claimed by the NCAA. Hint: Refer to slides 7-8 of Tuesday lecture 1.
alternative hypothesis
A hypothesis test gives a p-value of 0.30. If the significance level α = 0.05, the results are said to be
not statistically significant because the p-value > α.
Determine if the following statement is a typical null hypothesis (Ho) or alternative hypothesis (Ha): There is no difference between the proportion of overweight men and overweight women in America. Hint: Refer to slides 7-8 of Tuesday lecture 1.
null hypothesis
Null and alternative hypotheses are statements about
population parameters
The designated level (typically set at 0.05) to which the p-value is compared to, in order to decide whether the alternative hypothesis is accepted or not is called a
significance level
A hypothesis test gives a p-value of 0.03. If the significance level α = 0.05, the results are said to be
statistically significant because the p-value < α
When the p-value is less than or equal to the designated level of 0.05, the result is called a
statistically significant result
The smaller the p-value, the
stronger the evidence against the null hypothesis.
A two-sided or two-tailed hypothesis test is one in which
the alternative hypothesis includes values in either direction from a specific standard
If the result of a hypothesis test for a proportion is statistically significant, then
the null hypothesis is rejected
