Applied Statistic Final
If radio station call letters must begin with either K or W and must include either two or three additional letters, how many different possibilities are there?
2*26^2*27 = 36504
Is the number of fish caught during a fishing tournament a discrete random variable, a continuous random variable, or not a random variable?
discrete
Is the number of points scored during a basketball game a discrete random variable, a continuous, or not.
discrete
Events that are _______ cannot occur at the same time.
disjoint
The measure of center that is the value that occurs with the greatest frequency is the _______.
mode
Is the eye color of people on commercial aircraft flights a discrete random variable, a continuous random variable, or not a random variable?
not random variable
Which word is associated with multiplication when computing probabilities? (Not, Or, And, Disjoint)
And
The blood platelet counts of a group of women have a bell-shaped distribution with a mean of 258.4 and a standard deviation of 62.4 . (All units are 1000 cells/muL.) Using the empirical rule, find each approximate percentage below.
Approximately 68%of women in this group have platelet counts within 1 standard deviation of the mean, or between 196.0 and 320.8 Approximately 95% of women in this group have platelet counts between 133.6 and 383.2
Two events A and B are _______ if the occurrence of one does not affect the probability of the occurrence of the other.
independent
A presidential candidate plans to begin her campaign by visiting the capitals in 3 of 46 states. What is the probability that she selects the route of three specific capitals?
1/91080
Which of the following is NOT a voluntary response sample? Choose the correct answer below. A. A radio station asks for call-in responses to a question concerning city recycling. B. Quiz scores from a college level statistics course are analyzed to determine student progress. C. A local dentist asks her patients to fill out a questionnaire and mail it back to determine the quality of the care received during an office visit. D. A survey is taken at a mall by asking passersby if they will fill out the survey.
B. Quiz scores from a college level statistics course are analyzed to determine student progress.
In horse racing, a trifecta is a bet that the first three finishers in a race are selected, and they are selected in the correct order. Does a trifecta involve combinations or permutations? Explain.
Because the order of the first three finishers does make a difference, the trifecta involves permutations.
Heights of adults males are normally distributed. If a large sample of heights of adults males is randomly selected and the height are illustrated in a histogram, what is the shape of that histogram?
Bell-shaped.
Identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. To determine customer opinion of their safety features, Toyota randomly selects 30 dealerships during a certain week and surveys all customers visiting the dealerships. Which type of sampling is used?
Cluster
Identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. A television station asks its viewers to call in their opinion regarding the desirability of programs in high definition TV. Which type of sampling is used?
Convenience
Identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. A radio station asks its listeners to call in their opinion regarding the format of the morning show. Which type of sampling is used?
Convenience.
Determine whether the value is from a discrete or continuous data set. Number of days of rainfall in a year is 15 Is the value from a discrete or continuous data set?
Discrete
Is the number of people in a restaurant that has a capacity of 250 a discrete random variable, a continuous random variable, or not a random variable?
Discrete
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Years of elections: 1988, 1990, 1992, 1994, and 1996 Choose the correct answer below. Ordinal Interval Ratio Nominal
Interval
How is the result affected by the additional information that the survey subjects volunteered to respond?
It is very possible that the result is not valid because the sample may not be representative of the people who use public Wi-Fi.
The complement of "at least one" is _______.
NONE
Would it be unlikely for a driver in that age bracket to be involved in a car crash this year?
No
Is it unlikely for a household to have four or more cell phones in use?
No, because the probability of a respondent with four or more cell phones in use is greater than 0.05.
Is the standard deviation of the sample a good estimate of the variation of salaries of TV personalities in general?
No, because the sample is not representative of the whole population.
Twenty different statistics students are randomly selected. For each of them, their body temperature (degrees C) is measured and their head circumference (cm) is measured. If it is found that r=0, does that indicate that there is no association between these two variables?
No, because while there is no linear correlation, there may be a relationship that is not linear.
Is 6 a significantly high number of girls in 8 births? Why or why not? Use 0.05 as the threshold for a significant event.
No, since the appropriate probability is greater than 0.05, it is not a significantly high number.
If we find that there is a linear correlation between the concentration of carbon dioxide in our atmosphere and the global temperature, does that indicate that changes in the concentration of carbon dioxide cause changes in the global temperature?
No. The presence of a linear correlation between two variables does not imply that one of the variables is the cause of the other variable.
Which of the following is NOT a requirement of the Permutations Rule, , for items that are all different?
Order is not taken into account (rearrangements of the same items are considered to be the same).
Confusion of the inverse occurs when we incorrectly believe
P(B|A) = P(A|B)
Is a pulse rate of 127.9 beats per minute significantly low or significantly high?
Significantly high, because it is greater than two standard deviations above the mean.
Which probability is relevant for determining whether 1 is a significantly low number of girls in 8 births: the result from part (a) or part (b)?
Since getting 0 girls is an even lower number of girls than getting 1 girl, the result from part (b) is the relevant probability.
Identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. To estimate the percentage of defects in a recent manufacturing batch, a quality control manager at Microsoft selects every 18th software CD that comes off the assembly line starting with the eighth until she obtains a sample of 110 software CDs. Which type of sampling is used?
Systematic
Which of the following is NOT a requirement of the Combinations Rule, , for items that are all different?
That order is taken into account (consider rearrangements of the same items to be different sequences)
For data sets having a distribution that is approximately bell-shaped, _______ states that about 68% of all data values fall within one standard deviation from the mean.
The Empirical Rule
Identify the level of measurement of the data, and explain what is wrong with the given calculation. In a survey, the hair colors of respondents are identified as 10 for brown hair, 20 for blond hair, 30 for black hair, and 40 for anythings else. The average (mean) is calculate for 639 respondents and the result is 22.3
The data are at the nominal level of measurement. What is wrong with the given calculation? Such data are not counts or measures of anything, so its makes no sense to compute their average (mean).
Are the events of selecting an order from Restaurant A and selecting an accurate order disjoint events?
The events are not disjoint because it is possible to receive an accurate order from Restaurant A.
Determine whether the given value is a statistic or a parameter. A homeowner measured the voltage supplied to his home on 304 days of a given year, and the average (mean) value is 103.1 volts.
The given value is a statistic for the year because the data collected represent a sample.
Who would suffer from a false positive result? Why?
The person tested would suffer because he or she would be suspected of using drugs when in reality he or she does not use drugs.
Is the probability low enough so that further testing of the individual samples is rarely necessary?
The probability is not low, so further testing of the individual samples will frequently be a necessary event.
Which probability is relevant for determining whether 6 is a significantly high number of girls in 8 births: the result from part (a) or part (b)?
The result from part b, since it is the probability of the given or more extreme result.
If your score on your next statistics test is converted to a z score, which of these z scores would you prefer: -2.00, minus 1.00, 0, 1.00, 2.00? Why?
The z-score of 2.00 is most preferable because it is 2.00 standard deviations above the mean and would correspond to the highest of the five different possible test scores.
Which of the following statements about correlation is true?
We say that there is a positive correlation between x and y if the x-values increase as the corresponding y-values increase.
Find the regression equation, letting the first variable be the predictor (x) variable. Using the listed lemon/crash data, where lemon imports are in metric tons and the fatality rates are per 100,000 people, find the best predicted crash fatality rate for a year in which there are 500 metric tons of lemon imports. Is the prediction worthwhile?
Use StatCrunch to find equation: State -> Regresstion -> Simple linear. Since common sense suggests there should not be much of a relationship between the two variables, the prediction does not make much sense.
When making predictions based on regression lines, which of the following is not listed as a consideration?
Use the regression line for predictions only if the data go far beyond the scope of the available sample data.
Is the probability high enough to be of concern to those in the 16 - 18 age bracket?
Yes
Is 1 a significantly low number of girls in 8 births? Why or why not? Use 0.05 as the threshold for a significant event.
Yes, since the appropriate probability is less than 0.05, it is a significantly low number.
Are there any outliers and, if so, are they likely to have much of an effect on the measures of variation?
Yes, the largest amounts are much higher than the rest of the data, and appear to be outliers. It is likely that these are having a large effect on the measures of variation.
State whether the data described below are discrete or continuous, and explain why. The numbers of majors offered by colleges. a/ The data are continuous because the data can take on any value in a interval. b/ The data are discrete because the data can only take on specific values. c/ The data are discrete because the data can take on value in a interval. d/ The data are continuous because the data can only take on specific values.
b/ The data are discrete because the data can only take on specific values.
Determine which of the four levels of measurements (nominal, ordinal, interval, ratio) is most appropriate for the data below. Ratings of novels. a/ The interval level of measurement is most appropriate because the data can be ordered, differences (obtained by subtraction) can be found and are meaningful, and there is no natural starting point. b/ The nominal level of measurement is most appropriate because the data cannot be ordered. c/ The interval level of measurement is most appropriate because the data can be ordered, but differences (obtained by subtraction) cannot be found and are meaningless. d/ The ratio level of measurement is most appropriate because that data can be ordered, differences (obtained by subtraction) can be found and are meaningful, and there is a natural starting point.
c/ The interval level of measurement is most appropriate because the data can be ordered, but differences (obtained by subtraction) cannot be found and are meaningless.
A particular country has 45 total states. If the areas of all 45 states are added and the sum is divided by 45, the result is 213,260 square kilometer. a/ The result is a statistic because it describes some characteristic of a sample. b/ The result is a statistic because it describes some characteristic of a population. c/ The result is a parameter because it describes some characteristic of a population. d/ The result is a parameter because it describes some characteristic of a sample.
c/ The result is a parameter because it describes some characteristic of a population.
Which of the following is NOT a measure of center? Choose the correct answer below. census mode median mean
census
A _______ probability of an event is a probability obtained with knowledge that some other event has already occurred.
conditional
Is the time it takes for a light bulb out a discrete random variable, a continuous random variable, or not a random variable?
continuous
Is the weight of a T- bone steak a discrete random variable, a continuous random variable, or not a random variable?
continuous random variable.
Determine whether the underlined number is a statistic or a parameter A sample of students is selected and t is found that 65% own a vehicle. a/ Parameter because the value is a numerical measurement describing a characteristic of a population. b/ Statistic because the value is a numerical measurement describing a characteristic of a population. c/ Parameter because the value is a numerical measurement describing a characteristic of a sample. d/ Statistic because the value is a numerical measurement describing a characteristic of a sample.
d/ Statistic because the value is a numerical measurement describing a characteristic of a sample.
The _______ of a discrete random variable represents the mean value of the outcomes.
expected value
The heights of the bars of a histogram corresponds to ________ values.
frequency
When determining whether there is a correlation between two variables, one should use a ____________ to explore the data visually.
scatterplot
A data value is considered _______ if its z-score is less than minus 2 or greater than 2.
significantly low or significantly high
Whenever a data value is less than the mean, _______.
the corresponding z-score is negative.
The square of the standard deviation is called the _______.
variance
A magazine published a list consisting of the state tax on each gallon of gas. If we add the 50 state tax amounts and then divide by 50, we get 27.3 cents. Is the value of 27.3 cents the mean amount of state sales tax paid by all U.S. drivers? Why or why not?
No, the value of 27.3 cents is not the mean because the 50 amounts are all weighted equally in the calculation, but some states consume more gas than others, so the mean amount of state sales tax should be calculated using a weighted mean.
