stats test 1
The data represents the body mass index (BMI) values for 20 females. Construct a frequency distribution beginning with a lower class limit of 15.0 and use a class width of 6.0. 17.7 33.5 26.7 22.2 24.5 27.9 21.8 18.3 29.5 21.5 19.2 21.8 24.2 37.7 36.7 28.4 44.9 30.9 27.2 24.9
15.0-20.9-3 21.0-26.9-8 27.0-32.9-5 33.0-38.9-3 39.0-44.9-1
The number of vehicles passing through a bank drive-up line during each 15-minute period was recorded. The results are shown below. Find the median number of vehicles going through the line in a 15-minute period. 25 27 25 28 28 25 30 27 35 31 31 29 24 31 25 20 15 27 27 27
27 vehicles
Several studies showed that after eating chocolate, subjects had increased blood levels of antioxidants. Antioxidants have been associated with decreased risk of heart disease. A candy company financed this research. Identify what is wrong.
It is questionable that the sponsor is a candy company because this sponsor can be greatly affected by the conclusion.
length f a rock song is 3.5 minutes
continues
An internet site asks its members to call in their opinion regarding their web
conviencie
The linear ________ coefficient denoted by r measures the ________ of the linear association between two variables.
correlation; strength
a researcher plans to obtain data by interviewing spouses of victims who perished in a tsunami to see how they're coping
cross-section
study involved 22,071 male physicians. Based on random selections, 11,037 of them were treated with aspirin and the other 11,034 were given placebos. The study was stopped early because it became clear that aspirin reduced the risk of myocardial infarctions by a substantial amount.
experiment apply a treatment to The results apply only to male physicians.
volume of planets in cubic meter
he ratio 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 a natural starting zero
The prices (in dollars) of 12 electric smooth top ranges are listed below. Find the range for the given sample data. 865 1010 655 565 1465 1110 710 765 820 1310 555 1065
910
In the data table below, the x-values are the weights (in pounds) of cars and the y-values are the corresponding highway fuel consumption amounts (in mi/gal). Weight (lb) 4070 3393 4139 3656 3557 Highway Fuel Consumption (mi/gal) 25 32 29 29 30 Given the context of the car measurement data, what issue can be addressed by conducting a statistical analysis of the values
Is there a relationship or an association between the weight of a car and its fuel consumption amount?
Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 539 human resource professionals, each was asked about the importance of the education of a job applicant. The survey subjects were randomly selected by pollsters from a reputable market research firm
It appears to be sound because the data are not biased in any way
In a survey of 711 human resource professionals, each was asked about the importance of the experience of a job applicant. The survey subjects were randomly selected by pollsters from a reputable market research firm.
It appears to be sound because the data are not biased in any way
In a survey, the responses of respondents are identified as 0 for a "yes", 1 for a "no", 2 for a "maybe", and 3 for anything else. The average (mean) is calculated for 736 respondents and the result is 1.1.
uch data are not counts or measures of anything, so it makes no sense to compute their average (mean).
Identify the type of sampling used (random, systematic, convenience, stratified, or cluster sampling) in the situation described below. In a poll conducted by a certain research center, 1282 adults were called after their telephone numbers were randomly generated by a computer, and 59% were able to correctly identify the
random sampling
In the data table below, the x-values are the weights (in pounds) of cars and the y-values are the corresponding highway fuel consumption amounts (in mi/gal). Weight (lb) 4067 3332 4109 3643 3514 Highway Fuel Consumption (mi/gal) 25 31 29 28 30 Given the context of the car measurement data, what issue can be addressed by conducting a statistical analysis of the values?
s there a relationship or an association between the weight of a car and its fuel consumption amount?
Several studies showed that after drinking red wine, subjects had increased blood levels of antioxidants. Antioxidants have been associated with decreased risk of heart disease. A wine company financed this research. Identify what is wrong.
t is questionable that the sponsor is a wine company because this sponsor can be greatly affected by the conclusion.
A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40 years. The blood pressure readings (in mm Hg) were given to the nearest whole number. What class width was used to construct the relative frequency distribution?
10 mm HG
The frequency distribution below summarizes the home sale prices in the city of Summerhill for the month of June. Determine the width of each class. Round to the nearest whole number as needed. A frequency distribution has two columns labeled from left to right "Sale Price (in thousands of dollars)" and "Frequency". The entry pairs in each row are given as follows, where the sale price is listed first and the frequency is listed second: 80.0 to 110.9, 2; 111.0 to 141.9, 5; 142.0 to 172.9, 7; 173.0 to 203.9, 10; 204.0 to 234.9, 3; 235.0 to 265.9, 1.
31
Find the standard deviation for the given sample data. Round your answer to one more decimal place than is present in the original data. 22.6 16.1 36.1 36.0 23.8 20.3
8.35
A research company uses a device to record the viewing habits of about 15,000 households, and the data collected over the past 6 years will be used to determine whether the proportion of households tuned to a particular news program increased.
A retrospective study
A researcher was once criticized for falsifying data. Among his data were figures obtained from 6 groups of rats, with 4 individual rats in each group. These values were given for the percentage of successes in each group: 53%, 58%, 63%, 46%, 48%, 67% . What's wrong with those values
All percentages of success should be multiples of 25. The given percentages cannot be correct.
A student's course grade is based on one midterm that counts as 20% of his final grade, one class project that counts as 5% of his final grade, a set of homework assignments that counts as 50% of his final grade, and a final exam that counts as 25% of his final grade. His midterm score is 66, his project score is 80, his homework score is 87, and his final exam score is 67. What is his overall final score? What letter grade did he earn (A, B, C, D, or F)? Assume that a mean of 90 or above is an A, a mean of at least 80 but less than 90 is a B, and so on.
His overall final score is 77.57 His letter grade is C.
In a survey of 754 subjects, each was asked how often he or she played sports. The survey subjects were internet users who responded to a question that was posted on a news website.
It is flawed because it is a voluntary response sample.
Jorge has his own business as a painter. The amounts he made in the last five months are shown below. Find the mean, median, and range of the data. $2426 $2463 $1451 $2154 $1119
Mean=$1923 Median=$2154 Range=$1344
The table below shows the frequency distribution of the rainfall on 52 consecutive Wednesdays in a certain city. Use the frequency distribution to construct a histogram. Do the data appear to have a distribution that is approximately normal? 0-0.19. 22 0.20-0.39. 12 0.40-0.59. 3
No, it is not symmetric.
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
When testing a new treatment, what is the difference between statistical significance and practical significance? Can a treatment have statistical significance, but not practical significance?
Statistical significance is achieved when the result is very unlikely to occur by chance. Practical significance is related to whether common sense suggests that the treatment makes enough of a difference to justify its use. It is possible for a treatment to have statistical significance, but not practical significance.
the numbers of voters that are registered with a certain political party in different regions
The data are discrete because the data can only take on specific values.
A magazine ran a survey about a web site for downloading music. Readers could register their responses on the magazine's web site. Identify what is wrong
The sample is a voluntary response sample, so there is a good chance that the results do not reflect the population.
The table lists weights (pounds) and highway mileage amounts (mpg) for seven automobiles. Use the sample data to construct a scatterplot. Use the first variable for the x-axis. Based on the scatterplot, what do you conclude about a linear correlation? Weight (lb) 3290 3310 3775 4260 4415 2250 3655 Highway (mpg) 31 30 26 24 22 39 27
Yes, as the weight increases the highway mileage decreases.
number of pieces of lumber used to make a deck is 113
discrete
A student earned grades of B, B, A, C, and D. Those courses had these corresponding numbers of credit hours: 4, 5, 1, 5, 4. The grading system assigns quality points to letter grades as follows: A=4, B=3, C=2, D=1, and F=0. Compute the grade point average (GPA) and round the result to two decimal places
2.37
227 239 215 219 221 233 229 233 235 228 245 231
21 5 9 22 1 7 8 9 23 1 3 3 5 9 24 5
The following data show the number of laps run by each participant in a marathon. 46 65 55 43 51 48 57 30 43 49 32 56
3,0 2 4,3 3 6 8 9 5,1 5 6 7 6,5
Scores Number of Students 0-19 2 20-39 4 40-59 6 60-79 15 80-99 5
49.5
The following frequency distribution displays the scores on a math test. Find the class boundaries of scores interval 50-59. Scores Number of Students 50-59 2 60-69 4 70-79 6 80-89 15 90-99 5
49.5, 59.5
Find the standard deviation for the given sample data. Round your answer to one more decimal place than the original data. 18 18 18 9 15 5 10 5 15
5.4
Construct the cumulative frequency distribution for the given data. Daily Low (°F) Frequency 35-39 2 40-44 4 45-49 6 50-54 9 55-59 5 60-64 6 65-69 1 Construct the cumulative frequency distribution.
Daily Low Temperature (°F) Cumulative Frequency Less than 40 2 Less than 45 6 Less than 50 12 Less than 55 21 Less than 60 26 Less than 65 32 Less than 70 33
In the data table below, the x-values are the weights (in pounds) of cars and the y-values are the corresponding highway fuel consumption amounts (in mi/gal). Weight (lb) 4037 3371 4142 3609 3562 Highway Fuel Consumption (mi/gal) 25 32 28 29 30 Given the context of the car measurement data, what issue can be addressed by conducting a statistical analysis of the values?
Is there a relationship or an association between the weight of a car and its fuel consumption amount?
In a data set with a range of 55.4 to 105.4 and 400 observations, there are 276 observations with values less than 86. Find the percentile for 86
P69
A group of adult males has foot lengths with a mean of 26.89 cm and a standard deviation of 1.28 cm. Use the range rule of thumb to identify the limits separating values that are significantly low or significantly high. Is the adult male foot length of 24.0 cm significantly low or significantly high? Explain.
Significantly low values are 24.3324.33 cm or lower. Significantly high values are 29.4529.45 cm or higher. The adult male foot length of 24.0 cm is significantly low because it is less than 24.3324.33 cm.
the numbers of checked bags on flights between San Fran and atlanta
The data are discrete because the data can only take on specific values.
A homeowner measured the voltage supplied to his home on 5 days of a given week, and the average (mean) value is 138.5 volts.
The given value is a statistic for the week because the data collected represent a sample.
The table shows the magnitudes of the earthquakes that have occurred in the past 10 years. Use the frequency distribution to construct a histogram. Does the histogram appear to be skewed? If so, identify the type of skewness. Earthquake magnitude Frequency 5.0-5.9 13 6.0-6.9 14 7.0-7.9 9 8.0-8.9 6 9.0-9.9 1
The histogram has a longer right tail, so the distribution of the data is skewed to the right.
The histogram to the right represents the weights (in pounds) of members of a certain high-school programming team. How many team members are included in the histogram?
The histogram represents 1919 programming team members.
the chance of plaque on teeth by over 300 percent." What is wrong with thisstatement?
a reduction f 1005 WOULD ELIMINATE
In a study of 391 boys with a particular disease, the subjects were monitored with an EEG
he given description corresponds to an observational study.
In a survey of 754 human resource professionals, each was asked about the importance of the education of a job applicant. The survey subjects were randomly selected by pollsters from a reputable market research firm.
it appears to be sound because the data are not biased in any way.
1.2-1.6. 5 1.7-2.1 2 2.2-2.6. 5
less than 1.7. 5 less than 2.2 7
Identify the cumulative frequency distribution that corresponds to the given frequency distribution. A frequency distribution has two columns labeled from left to right "Speed" and "Number of Cars". The entry pairs in each row are given as follows, where the speed is listed first and the number of cars is listed second: 0 to 29, 4; 30 to 59, 16; 60 to 89, 60; 90 to 119, 20.
less than 30- 4
Fourteen different second-year medical students at a hospital measured the blood pressure of the same person. The systolic readings (mm Hg) are listed below. Use the given data to construct a boxplot and identify the 5-number summary. 138 150 135 126 120 125 149 130 147 126 149 140 131 150
middle line at 35
favorite films
nominal
favorite types of music
nominal
in a study of all 2918 at a college, it is found that 45% own a computer
parameter because the value is a numerical measurement describing the characteristics of. a populationl
A large company wants to administer a satisfaction survey to its current customers. Using their customer database, the company randomly selects 70 customers and asks them about their level of satisfaction with the company.
random
ages of children 3,4,5,6
ratio
a market researcher has partitioned all residents of a certain region into categories of unemployed, employed full time, and employed part time. She is surveying 52 people from each category
startified sampling
a sample of students is selected and it is found that 40% own a vehicle
statistic because the value is a numerical measurement describing a characteristic of a sample
a sample of employees is selected and it is found that 45% own a television
statistic because the value is a numerical measurement describing a characteristic sample
To determine her heart rate, Carrie divides up her day into three parts: morning, afternoon, and evening. She then measures her heart rate at 4 randomly selected times during each part of the day.
stratified
A woman is selected by a marketing company to participate in a paid focus group. The company says that the woman was selected because she was randomly chosen from all women in her tax bracket.
stratified sampling
a market researcher has partitioned all residents of a certain region into categories of young middle aged and senior she is surveying 53 people
stratified sampling
A researcher selects every 138th social security number and surveys the corresponding person.
systematic sampling
To estimate the percentage of defects in a recent manufacturing batch, a quality control manager at Toshiba selects every 14th laptop that comes off the assembly line starting with the second until she obtains a sample of 80 laptops.
systemic
the political party affiliations of poll respondents
the data are qualitative because they don't meanture or count anything
Years in which U.S. presidents were inaugurated
the interval level of measurement is most
A particular country has 55 total states. If the areas of all 55 states are added and the sum is divided by 55, the result is 212,958 square kilometers. Determine whether this result is a statistic or a parameter.
the result is a parameter because it describes some characteristic of a population.
The graph to the right uses cylinders to represent barrels of oil consumed by two countries. Does the graph distort the data or does it depict the data fairly? Why or why not? If the graph distorts the data, construct a graph that depicts the data fairly. 21.2 5.3
Yes, because the graph incorrectly uses objects of volume to represent the data
The local Tupperware dealers earned the following commissions last month. What was the mean commission earned? Round your answer to the nearest cent. $2894.21 $1777.15 $2144.77 $4096.37 $4046.29 $1786.37 $3296.69 $4086.27 $2784.22 $4027.79
$3094.01
In the data table below, the x-values are the weights (in pounds) of cars and the y-values are the corresponding highway fuel consumption amounts (in mi/gal). Weight (lb) 4046 3315 4185 3662 3539 Highway Fuel Consumption (mi/gal) 27 32 28 29 30 Comment on the source of the data if you are told that car manufacturers supplied the values. Is there an incentive for car manufacturers to report values that are not accurate?
. Yes, because consumers, in general, would prefer to buy a car with a higher level of fuel efficiency. In this case, the source of the data would be suspect with a potential for bia
Attendance records at a school show the number of days each student was absent during the year. The days absent for each student were as follows. 0 1 3 2 4 4 2 3 5 4 2 2 5 Which of these choices display the correct dotplot?
0-1 1-1 2-4 3-2 4-3 5-2
ReviewHomework:Homework 3 (3.1, 3.2, 3.3) Question 1, 3.1-1 HW Score: 100%, 32 of 32 points Points: 1 of 1 Close A store manager kept track of the number of newspapers sold each week over a seven-week period. The results are shown below. 81 71 202 113 269 248 242 Find the median number of newspapers sold.
202 newspapers
The mean of a set of data is 108.06 and its standard deviation is 115.45. Find the z-score for a value of 489.67.
3.31
The race speeds (in minutes) for the top eight cars in a 200-mile race are listed below. Use the range rule of thumb to estimate the standard deviation. Round results to the nearest tenth. 181.0 180.6 189.2 182.2 175.6 180.0 177.9 181.8
3.4 minutes
A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40 years. The blood pressure readings were given to the nearest whole number. Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading between 110 and 119 mm Hg inclusive?
35%
To get the best deal on a microwave oven, Jeremy called six appliance stores and asked the cost of a specific model. The prices he was quoted are listed below. Find the variance for the given data. Round your answer to one more decimal place than the original data. $663 $273 $410 $622 $174 $374
36,838.3 dollars
Refer to the table summarizing service times (seconds) of dinners at a fast food restaurant. How many individuals are included in the summary? Is it possible to identify the exact values of all of the original service times? Time (sec) Frequency 60-119 7 120-179 24 180-239 12 240-299 3 300-359
51 individuals are included in the summary. No. The data values in each class could take on any value between the class limits, inclusive.
Listed below are the amounts of time (in months) that the employees of a restaurant have been working at the restaurant. Find the mean for the given sample data. Round your answer to one more decimal place than the original data values. 1 5 6 8 11 14 17 46 61 90 99 126 143 167
56.7 months
Use the given sample data to find Q3. 49 52 52 52 74 67 55 55
61.0
Find the variance for the given sample data. Round your answer to one more decimal place than the original data. 7 7 2 5 1
7.8
se people aged between 25 and 40 years. The blood pressure readings were given to the nearest whole number. Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading between 110 and 139 mm Hg inclusive?
75%
The following frequency distribution depicts the scores on a math test. Find the class midpoint of scores for the interval 95-99. Scores Number of Students 75-79 2 80-84 4 85-89 6 90-94 15 95-99 5
97.0
when a car is randomly selected and weighed, It is found to weigh 1671.kg
A continuous data set because there are infinitely many possible values and those values cannot be counted
The data represents the daily rainfall (in inches) for one month. Construct a frequency distribution beginning with a lower class limit of 0.00 and use a class width of 0.20. Does the frequency distribution appear to be roughly a normal distribution?
No, the distribution is not symmetric and the frequencies do not start off low.
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
A study of an association between which ear is used for cell phone calls and whether the subject is left-handed or right-handed began with a survey e-mailed to 5000 people belonging to an otology online group, and 717 surveys were returned. (Otology relates to the ear and hearing.) What percentage of the 5000 surveys were returned? Does that response rate appear to be low? In general, what is a problem with a very low response rate?
Of the 5000 surveys, 1414% were returned. This response rate appears to be low. t creates a serious potential for getting a biased sample that consists of those with a special interest in the topic.
The scatterplot below displays the amount of nitrous oxide (NO) explained by the amount of carbon monoxide (CO) emissions in million metric tons over a ten year period in the United States. Select the choice that best describes any relationship between the variables.
Overall, there is no noticeable relationship between NO and CO.
n a poll conducted by a certain research center, 874 adults were called after their telephone numbers were randomly generated by a computer, and 15% were able to correctly identify the secretary of state
Random sampling
A certain group of test subjects had pulse rates with a mean of 82.5 beats per minute and a standard deviation of 10.6 beats per minute. Use the range rule of thumb to identify the limits separating values that are significantly low or significantly high. Is a pulse rate of 53.7 beats per minute significantly low or significantly high
Significantly low values are 61.3 beats per minute or lower Significantly high values are 103.7 beats per minute or higher. significantly low because it is more than two standard deviations below the mean
n a set of data, blood lead levels are represented as 10 for low, 20 for medium, and 30 for high. The average (mean) of the 728 blood lead levels is 25.4.
Such data should not be used for calculations such as an average.
alert system of yellow (lowest), orange, and red
The ordinal level of measurement is most appropriate because the data can be ordered, but differences (obtained by subtraction) cannot be found or are meaningless.
Close Refer to the sample of body temperatures (degrees Fahrenheit) in the table below. Given these temperatures, what issue can be addressed by conducting a statistical analysis of the data? Subject 8 AM 97.0 98.5 97.6 97.7 98.7 12 AM 97.6 97.8 98.0 98.4 98.4
The data can be used to address the issue of whether there is a correlation between body temperatures at 8 AM and at 12 AM. Your answer is correct. B.
Listed below are body temperatures (°F) of healthy adults. Why is it that a graph of these data would not be very effective in helping us understand the data? 98.6 98.6 98.0 98.0 99.0 98.4 98.4 98.4 98.4 98.6
The data set is too small for a graph to reveal important characteristics of the data
Currently, there is no approved vaccine for the prevention of infection by a certain virus. A clinical trial of a possible vaccine is being planned to include subjects treated with the vaccine while other subjects are given a placebo.
The most appropriate is completely randomized design.
If we collect a large sample of blood platelet counts and if our sample includes a single outlier, how will that outlier appear in a histogram?
The outlier will appear as a bar far from all of the other bars with a height that corresponds to a frequency of 1.
ReviewTest:PRACTICE 1530 Test 1 Question 17, 3.2.7 Test Score: 15%, 15 of 100 points Points: 0 of 5 Close Listed below are the top 10 annual salaries (in millions of dollars) of TV personalities. Find the range, variance, and standard deviation for the sample data. Given that these are the top 10 salaries, do we know anything about the variation of salaries of TV personalities in general? 40 38 37 30 21 19 16 14 13.6 13.0
The range of the sample data is $27.027.0 million The variance of the sample data is 120.43120.43. ( The standard deviation of the sample data is $10.9710.97 m No, because the sample is not representative of the whole population.
A movie with a 4-star rating is twice as good as one with a 2-star rating.
The ratio level of measurement does not apply.
A newspaper posted this question on its website: "How often do you seek medical information online?" Of 1072 Internet users who chose to respond, 38% of them responded with "frequently." What term is used to describe this type of survey in which the people surveyed consist of those who decided to respond? What is wrong with this type of sampling method?
The respondents are a voluntary response sample. The respondents are a self-selected sample. what is wrong Responses may not reflect the opinions of the general population. Many people may choose not to respond to the survey.
A particular country has 60 total states. If the areas of all 60 states are added and the sum is divided by 60, the result is 180,081 square kilometers. Determine whether this result is a statistic or a parameter.
The result is a parameter because it describes some characteristic of a population
In a double-blind experiment designed to test the effectiveness of a new medication as a treatment for lower back pain, 1643 patients were randomly assigned to one of three groups: (1) the 547 subjects in the placebo group were given pills containing no medication; (2) 550 subjects were in a group given pills with the new medication taken at regular intervals; (3) 546 subjects were in a group given pills with the new medication to be taken when needed for pain relief.
The subjects in the study did not know whether they were taking a placebo or the new medication, and those who administered the pills also did not know.
n a double-blind experiment designed to test the effectiveness of a new medication as a treatment for lower back pain, 1643 patients were randomly assigned to one of three groups: (1) the 547 subjects in the placebo group were given pills containing no medication; (2) 550 subjects were in a group given pills with the new medication taken at regular intervals; (3) 546 subjects were in a group given pills with the new medication to be taken when needed for pain relief. What does it mean to say that the experiment was "double-blind"?
The subjects in the study did not know whether they were taking a placebo or the new medication, and those who administered the pills also did not know.
A defunct website listed the "average" annual income for Florida as $35,031. What is the role of the term average in statistics? Should another term be used in place of average?
The term average is not used in statistics. The term mean should be used for the result obtained by adding all of the sample values and dividing by the total number of sample values
Determine whether the given value is a statistic or a parameter. A study was conducted of all 2654 car owners in a certain country
The value is a parameter because it is a numerical measurement describing some characteristic of a population.
If your score on your next statistics test is converted to a z score, which of these z scores would you prefer: −2.00, −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.
Determine whether the source given below has the potential to create a bias in a statistical study. A certain medical organization tends to oppose the use of meat and dairy products in our diets, and that organization has received hundreds of thousands of dollars in funding from an animal rights foundation.
There does appear to be a potential to create a bias. There is an incentive to produce results that are in line with the organization's creed and that of its funders.
For a data set of weights (pounds) and highway fuel consumption amounts (mpg) of ten types of automobile, the linear correlation coefficient is found and the P-value is 0.028. Write a statement that interprets the P-value and includes a conclusion about linear correlation.
The P-value indicates that the probability of a linear correlation coefficient that is at least as extreme is 2.82.8%, which is low, so there is sufficient evidence to conclude that there is a linear correlation between weight and highway fuel consumption in automobiles.
For a data set of brain volumes (cm3) and IQ scores of nine males, the linear correlation coefficient is found and the P-value is 0.271. Write a statement that interprets the P-value and includes a conclusion about linear correlation.
The P-value indicates that the probability of a linear correlation coefficient that is at least as extreme is 27.127.1%, which is high, so there is not sufficient evidence to conclude that there is a linear correlation between brain volume and IQ score in males.
For a data set of brain volumes (cm3) and IQ scores of four males, the linear correlation coefficient is found and the P-value is 0.835. Write a statement that interprets the P-value and includes a conclusion about linear correlation.
The P-value indicates that the probability of a linear correlation coefficient that is at least as extreme is 83.583.5%, which is high, so there is not sufficient evidence to conclude that there is a linear correlation between brain volume and IQ score in males
For a data set of brain volumes (cm3) and IQ scores of eight males, the linear correlation coefficient is found and the P-value is 0.544. Write a statement that interprets the P-value and includes a conclusion about linear correlation.
The P-value indicates that the probability of a linear correlation coefficient that is at least as extreme is 54.454.4%, which is high, so there is not sufficient evidence to conclude that there is a linear correlation between brain volume and IQ score in males. (Type an integer or a decimal. Do not round.)
A successful basketball player has a height of 6 feet 10 inches, or 208 cm. Based on statistics from a data set, his height converts to the z score of 4.81. How many standard deviations is his height above the mean?
The player's height is 4.81 standard deviation(s) above the mean.
A study involved 22,071 male physicians. Based on random selections, 11,037 of them were treated with aspirin and the other 11,034 were given placebos. The study was stopped early because it became clear that aspirin reduced the risk of myocardial infarctions by a substantial amount.
This is an experiment because the researchers apply a treatment to the individuals. -The results apply only to male physicians.
A sociologist has created a brief survey to be given to 2000 adults randomly selected from the U.S. population. Here are her first two questions: (1) Have you ever been the victim of a felony crime? (2) Have you ever been convicted of a felony?
This is an observational study because the researcher does not attempt to modify the individuals. individuals convicted of a felony are more likely to not answer the second question honestly.
A medical researcher tested for a difference in systolic blood pressure levels between male and female students who are 12 years of age. She randomly selected four males and four females for her study.
This is an observational study because the researcher does not attempt to modify the individuals. The sample is too small.
polling company reported that 27% of 1018 surveyed adults said that rising gas prices are "very harmful." Complete parts (a) through (d) below.
What is the exact value that is 27% of 1018? The exact value is 274.86 No, the result from part (a) could not be the actual number of adults who said that rising gas prices are "very harmful" because a count of people must result in a whole number. The actual number of adults with this opinion could be 275 Among the 1018 respondents, 191 said that rising gas prices are "not at all harmful." What percentage of respondents said that rising gas prices are "not at all harmful"? 18.76%
The population of ages at inauguration of all U.S. Presidents who had professions in the military is 62, 46, 68, 64, 57. Why does it not make sense to construct a histogram for this data set?
With a data set that is so small, the true nature of the distribution cannot be seen with a histogram
The population of ages at inauguration of all U.S. Presidents who had professions in the military is 62, 46, 68, 64, 57. Why does it not make sense to construct a histogram for this data set?
With a data set that is so small, the true nature of the distribution cannot be seen with a histogram.
Construct a scatter diagram using the data table to the right. This data is from a study comparing the amount of tar and carbon monoxide (CO) in cigarettes. Use tar for the horizontal scale and use carbon monoxide (CO) for the vertical scale. Determine whether there appears to be a relationship between cigarette tar and CO
Yes, as the amount of tar increases the amount of carbon monoxide also increases.
Does the frequency distribution appear to have a normal distribution? Explain. Temperature (°F) Frequency 35-39 1 40-44 4 45-49 5 50-54 12 55-59 5 60-64 3 65-69 1
Yes, because the frequencies start low, proceed to one or two high frequencies, then decrease to a low frequency, and the distribution is approximately symmetric.
Refer to the table of body temperatures (degrees Fahrenheit). Is there some meaningful way in which each body temperature recorded at 8 AM is matched with the 12 AM temperature? Subject 8 AM 97.0 98.5 97.6 97.7 98.7 12 AM 97.6 97.8 98.0 98.4 98.4
Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same subject, so each pair is matched.
In a study designed to test the effectiveness of a medication as a treatment for lower back pain, 1643 patients were randomly assigned to one of three groups: (1) the 547 subjects in the placebo group were given pills containing no medication; (2) 550 subjects were in a group given pills with the medication taken at regular intervals; (3) 546 subjects were in a group given pills with the medication to be taken when needed for pain relief. In what specific way was replication applied in the study?
he group sample sizes are all large so the researchers could see the effects of the treatment.
A drug is designed to treat insomnia. In a clinical trial of the drug, amounts of sleep each night are measured before and after subjects have been treated with the drug.
he most appropriate is matched pairs design.
your odds of bike theft by 300 percent." What is wrong with thisstatement
if the device eliminate all bike thefts, it would
years of elations 1988, 1992, 1996, 2000, and 2004
interval
dentify the cumulative frequency distribution that corresponds to the given frequency distribution. A frequency distribution has two columns labeled from left to right "Speed" and "Number of Cars". The entry pairs in each row are given as follows, where the speed is listed first and the number of cars is listed second: 0 to 29, 4; 30 to 59, 16; 60 to 89, 60; 90 to 119, 20.
less than 30- 4 less than 60-20 less than 90-80
Research is conducted to determine if there is a relation between hearing loss and exposure to mumps.
observational study
The following frequency distribution analyzes the scores on a math test. Find the class boundaries of scores interval 90-99. Scores Number of Students 50-59 2 60-69 4 70-79 6 80-89 15 90-99 5
89.5, 99.5
