Jeopardy Statistics Edition
JeopardyStatistics Edition
TermsGeneral
ProbabilitySampling
DistributionsConfidenceIntervals
HypothesisTests:
Proportions
Hypothesis Tests:Means
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$200
FinalJeopardy
CATEGORY:
Hypothesis Tests
Final Jeopardy
A sample of 80 is collected in which there are 62 successes.
This is the type of error we risk making when testing the hypotheses:
H0: p = 0.70
Ha: p ≠ 0.70
Final Jeopardy
What is a Type II error since we would Fail to Reject H0?
Running 1-PropZTest
z = 1.464
P-value = 0.1432
Terms: $200
• The number of outcomes in event E divided by the total number of possible outcomes.
Terms: $200
• What is P(E) or the probability of event E?
?
Terms: $400
• Two events that cannot occur simultaneously.
Terms: $400
• What are disjoint or mutually exclusive events?
?
Terms: $600
• Whether or not one event occurs has no bearing on whether or not another event occurs.
• P(E|F) = P(E)
Terms: $600
• What are independent events?
?
Terms: $800
• The probability of getting a sample comparable to the one we have under the assumption that the null hypothesis is correct.
Terms: $800
• What is the P-value of a hypothesis test?
?
Terms: $1000
• The value of some probability variable corresponding to the sample data collected.
Terms: $1000
• What is the test statistic for a hypothesis test?
?
General Probability: $200
• There are 20 marbles in a bag, 5 each of colors red, white, blue, and green. Each color is numbered 1 through 5.
• One marble is selected. This is the probability that it is blue.
General Probability: $200
• What is 5/20 = 0.25?
?
General Probability: $400
• There are 20 marbles in a bag, 5 each of colors red, white, blue, and green. Each color is numbered 1 through 5.
• One is selected at random. This is the probability that it is red or has the number 2 or 5 on it.
General Probability: $400
• What is 11/20 = 0.55?
?
General Probability: $600
• There are 20 marbles in a bag, 5 each of colors red, white, blue, and green. Each color is numbered 1 through 5.
• Three are selected at random without replacement. This is the probability that at least one of the marbles is blue.
General Probability: $600
• What is 1 – (15/20)*(14/19)*(13/18)
= 0.6009?
?
General Probability: $800
• A check of dorm rooms on a certain college campus revealed that 38% had refrigerators (R), 54% had TVs (T), and 21% had both.
• This is the value and meaning of P(T|RC).
General Probability: $800
• What is the probability that the room has a TV given that it does not have a refrigerator?
0.33/(0.33 + 0.29) = 0.5323?
?
General Probability: $1000• A recent Maryland highway safety study found
that in 77% of all accidents, the driver was wearing a seatbelt (S). Of those wearing a seatbelt, 92% escaped serious injury (I) but only 63% of those not wearing a seatbelt escaped serious injury. One driver is randomly selected.
• This is the meaning and value of P(SC|IC)
General Probability: $1000
• What is the probability that the driver was not wearing a seatbelt given that (s)he did not escape serious injury?
?
Sampling Distributions: $200
• At a certain company, it is believed that 84% of the employees approve the new benefits package that is being considered. A random sample of 68 employees is selected.
• These are the center, shape, and spread of the distribution of the sample proportion that approve the benefits package.
Sampling Distributions: $200
• What is a normal distribution with mean 0.84 and standard deviation 0.0445?
?
Sampling Distributions: $400
• At a certain company, it is believed that 84% of the employees approve the new benefits package that is being considered. A random sample of 68 employees is selected.
• This is the probability that less than 80% of the sample approve of the new benefits package.
Sampling Distributions: $400
• What is 0.1844?
?
Sampling Distributions: $600
• At a certain company, the average salary is $54000 with a standard deviation of $7800. A sample of 36 employees is chosen at random from this company.
• These are the center, shape, and spread of the distribution of the sample mean for such samples.
Sampling Distributions: $600
• What is a normal distribution with mean $54000 and standard deviation $1300?
?
Sampling Distributions: $800
• At a certain company, the average salary is $54000 with a standard deviation of $7800. A sample of 36 employees is chosen at random from this company.
• This is the probability that the average salary of this sample is more than $58000.
Sampling Distributions: $800
• What is 0.0010?
?
Sampling Distributions: $1000
• At a certain company, the average salary is $54000 with a standard deviation of $7800. A sample of 36 employees is chosen at random from this company.
• These average salaries make up the highest 0.5% of all such average salaries.
Sampling Distributions: $1000
• What is $57348.58 and above?
?
Confidence Intervals: $200
• This is the 97.4% CI for a population mean constructed from a sample of size 15 with mean 174.6mg and standard deviation 28.3mg if we assume the population is normally distributed.
Confidence Intervals: $200
• What is (156.41mg, 192.79mg)?
• Using Tinterval with “Stats” given
?
Confidence Intervals: $400
• This is equal to half the width of a
confidence interval.
Confidence Intervals: $400
• What is the margin of error of the confidence interval?
?
Confidence Intervals: $600
• This is the minimum sample size that should be used if we want to construct a 95% CI for a population proportion with a margin of error of no more than 4.5 percentage points.
Confidence Intervals: $600
• What is 475 subjects?
?
Confidence Intervals: $800
• This is the minimum sample size that should be obtained if we want to construct a 90% CI for a population mean with margin of error no more than 7.2 when previous studies support that s = 42.8.
Confidence Intervals: $800
• What is 96 subjects?
?
Confidence Intervals: $1000
• This is what happens to a CI if we keep the confidence level the same but we increase the sample size.
Confidence Intervals: $1000
• What is the margin of error decreases resulting in a more narrow confidence interval?
?
Hyp. Tests: Proportions: $200
• This is the P-value of a two-tailed test that has test statistic z = -2.45.
Hyp. Tests: Proportions: $200
• What is 0.0143?
?
Hyp. Tests: Proportions: $400
• This is the P-value for a hypothesis test having:
H0: p1 = 0.2, p2 = 0.4, p3 = 0.3, p4 = 0.1
Test statistic: X 2 = 10.42
Hyp. Tests: Proportions: $400
• What is 0.0153?
?
Hyp. Tests: Proportions: $600
• This is the “command” used in the calculator to, using the P-value approach, test the hypotheses :
H0: p1 = p2
Ha: p1 < p2
Hyp. Tests: Proportions: $600
• What is 2-PropZTest?
?
DailyDouble
Hyp. Tests: Proportions: $800
• This is the test statistic obtained from a sample of size 90 in which there were 62 ”successes” for the hypotheses:
H0: p = 0.72
Ha: p < 0.72
Hyp. Tests: Proportions: $800
• What is z = -0.6573?
?
Hyp. Tests: Proportions: $1000
• This is the 95% CI and conclusion reached for a sample of size 300 having 210 “successes” for the hypotheses:
H0: p = 0.75
Ha: p ≠ 0.75
Hyp. Tests: Proportions: $1000
• What is (0.64814, 0.75186) and thus we Fail to Reject H0?
Using 1-PropZInt and noticing 0.75 is in the interval.
?
Hyp. Tests: Means: $200
• This is what we must know in order to use the z statistic (rather than t) for a hypothesis test about a single population mean.
Hyp. Tests: Means: $200
• What is σ, the population’s standard deviation?
?
Hyp. Tests: Means: $400
• This is the validity needed when performing a ZTest.
Hyp. Tests: Means: $400
• What is one of:
(i) normal population
(ii) large sample size (C.L.T.)
(iii) a fairly linear normal plot
?
Hyp. Tests: Means: $600
• This is the P-value for a sample of size 10 from a normal population that produced test statistic t = -1.34 for the hypotheses:
H0: μ = 78
Ha: μ ≠ 78
Hyp. Tests: Means: $600
• What is 0.2131?
?
Hyp. Tests: Means: $800
• This is the test statistic and P-value obtained from a sample of size 16 with mean 1472.4 hours and standard deviation 184.6 hours for the hypotheses:
H0: μ = 1400
Ha: μ > 1400
Hyp. Tests: Means: $800
• What is t = 1.57 with P-value = 0.0686?
?
Hyp. Tests: Means: $1000
• One employee at a certain company believes that women in the company are earning, on average, less than men. A random sample of men and women are selected from this company. For the 175 women, the average salary was $41250 with a standard deviation of $2100. For the 200 men in the sample the average salary was $42000 with a standard deviation of $2400. These are the test statistic, P-value, and conclusion for the hypotheses:
H0: μf = μm
Ha: μf < μm
Hyp. Tests: Means: $1000
• What is t = -3.227, P-value = 0.00068, and thus we Reject H0 to conclude that on average, women do make less at this company than men?
Using 2-SampTTest
?