Statistics Questions and Answers

vast majority

Explain how to find the value for 96% confidence level.

Why is the median​ resistant, but the mean is​ not? Choose the correct answer below. A. The mean is not resistant because when data are​ skewed, there are extreme values in the​ tail, which tend to pull the mean in the direction of the tail. The median is resistant because the median of a variable is the value that lies in the middle of the data when arranged in ascending order and does not depend on the extreme values of the data. B. The mean is not resistant because it is dependent upon the sample​ size, n. The larger n​ is, the smaller the mean becomes.​ However, the median is resistant because it is not dependent on the sample​ size, n. C. The mean is not resistant because when data are​ skewed, there are extreme values in the​ tail, which do not pull the mean in that direction.​ However, the median is pulled in the direction of the extreme​ values, making it resistant. D. The median is​ resistant, while the mean is​ not, because when there are extreme values in the​ tail, the value of the median changes while the mean does not.

Which of the following statistics can turn negative? inflation rate GDP CPI unemployment rate

Simplicity of conducting the study is to ________ as ability to test large numbers of participants is to ________.

Give an example conceptualization and operationalization. How do they relate to each other

"Which of the following is an example of inferential statistics? Find the average height of 50 female students at State University. Summarize the variability of the exam scores of 40 students based on all 40 exam scores. Test the longevity of all light bulbs based on a sample of 100 light bulbs. Calculate a mutual fund's average return for the last five years."

"Which location experiences nearly 75% of the world's tornadoes? Group of answer choices Europe South Africa Eastern Asia United States"

Outline the advantages and disadvantages of the use of tally charts as quantitative data.

How do I find the t* at the 0.05 significance level?

"Herramienta utilizada para análisis un gráfico de datos bivariados Ishikawa Lógico Pareto Correlación Dispersión"

Theoretical frequency distributions provide an important basis in modern statistics.' Discuss.

Explain the difference between the functions STDEV.S() and STDEV.P() in Excel. What do the .S and .P extensions mean, and when would you apply each?

"Changing the Alpha level from .05 to .01 would. A. Decrease the risk of a type one and type two error. B. Increase the risk of a type one and type two error. C. Decrease the risk of a type one error and increase the risk of a type two error. D. Increase the risk of a type one error and decrease the risk of a type two error."

"What is the 2SD formula"

"The National Center for Education Statistics reported that 47% of college students work to pay for tuition and living expenses. Assume that a sample of 450 college students was used in the study. a. Provide a 95% confidence interval for the population proportion of college students who work to pay for tuition and living expenses. (to 2 decimals) , b. Provide a 99% confidence interval for the population proportion of college students who work to pay for tuition and living expenses. (to 2 decimals) , c. What happens to the margin of error as the confidence is increased from 95% to 99%?"

"A student entering a doctoral program in educational psychology is required to select two courses from the list of courses provided as part of his or her program. ​(a) List all possible two ​-course selections. ​(b) Comment on the likelihood that EPR 627 and EPR 631 will be selected. Select ten choices: A. 627,678 B.605,631 C.631,631 D.605,678 E.627,634 F.610,678 G.605,627 H.610,627 I.627,631 J.605,605 K.605,610 L. 678,631 M. 605,605,610 N.610,631"

"Which of these is an example of a blind experiment? a.) Asking a group of kids to choose their favorite candy from a jar containing different candies. b.)Asking a group of students about their favorite sports from a list containing names of 10 sports. c.)Asking a group of students about the candidate they will vote for in the school elections. d.)Asking a group of students to compare the tastes of different brands of potato chips without revealing the names of the brands."

Which of the following sampling methods would bias the set of responses? Select all that apply. A. Tossing a chipped number cube B. Interviewing pet owners about their pet's health C. Asking people to return a mail-in card D. Calling people between 3:00 PM and 4:00 PM

What is the five-number summary for the data 0, 2, 2, 4, 5, 5, 5, 5, 7, 11? Minimum Q1 Median Q3 Maximum When the minimum, 0, is removed from the data set, what is the five-number summary? Minimum Q1 Median Q3 Maximum

Sophia's IQ score is 85. She performed as well or better than __________ percent of her agemates. A) 16 B) 36 C) 50 D) 85

What is the interquartile range of the data set? {18,17,10,25,20,20,30,18,18,30,25} Enter the answer in the box.

How can you calculate the margin of error using a TI-84 Plus CE calculator?

"What does a correlation coefficient of +0.5 indicate about a set of data? A. Strong positive correlation. B. Strong negative correlation. C. No correlation. D. The decision is not provided."

A standard deck of playing cards consists of 52 cards. All cards are divided into 4 suits, with 2 red suits and 2 black suits. Each suit contains 13 cards, including numbered cards 2 to 10, a jack, a queen, a king, and an ace. What is the probability that a randomly drawn card is either a 5 or a 2?

Choose the best definitions of parameter and statistic. A. A statistic is a variable that describes a sample and a parameter is a variable that describes a population. B. A parameter is an unknown characteristic of a group and a statistic is a known characteristic of a group. C. A statistic is a number that describes a population and a parameter is a number that describes a sample. D. A statistic is a number that describes a sample and a parameter is a number that describes a population. E. A parameter is a number that describes a population. F. A statistic is a number that is used to estimate a parameter.

What is the z-score with a confidence level of 95% when finding the margin of error for the mean of a normally distributed population from a sample? A. 0.99 B. 1.65 C. 1.96 D. 2.58

Which of the following sampling methods would bias the set of responses? Select all that apply. - ☐ A. asking people to return a mail-in card - ☐ B. tossing a chipped number cube - ☐ C. calling people between 3:00 P.M. and 4:00 P.M. - ☐ D. interviewing pet owners about their pet's health Which of the following is an example of a statistical experiment? - ☐ A. Twenty people in a neighborhood are asked if they want more streetlights on the street. - ☐ B. More streetlights are installed on one street and people are then asked if they like the change. - ☐ C. The number of accidents on the street is compared to last year's rate. - ☐ D. People are asked to call a number to comment about the need for new streetlights. Choose the word to describe the sampling method. The first ten people who show up for class are asked to fill out a form. This is a self-selected sample. Choose the word to describe the sampling method. All students whose ID numbers are divisible by 5 are asked about what music they like. This is a systematic sample. A student wants to study the effect of meditation on the time a person is able to balance on one leg. She finds 40 volunteers who have never meditated, and records their balance times. She selects 20 of them at random, and instructs them to practice meditation daily for two weeks. In two weeks, she records the balance times for all 40 volunteers again. What is the group of volunteers who were asked to meditate called? - ☐ A. the control group - ☐ B. the experimental group - ☐ C. the sample group - ☐ D. the study group

Which answer best describes a standard deviation? Read all answers and then choose the answer that is most complete and accurate. The standard deviation is the square root of the corresponding variance. The standard deviation is the average amount that scores in a distribution deviate from the mean of that distribution. The standard deviation is a measure of variability. All of the answers above correctly describe the standard deviation. None of the answers above correctly describe the standard deviation.

# Discuss the difference between $r$ and $\rho$. ## Choose the correct answers below. ## r represents the $\rho$ represents the sample correlation coefficient. critical value for the corre* tion coefficient. population correlation coefficient.

"In which situation is it best to use a line graph? A. When the values on both axes are numbers B. When a grade distribution is displayed C. When showing trends D. When representing parts of a whole"

# ASSESSMENT Read each item carefully. Write the letter of the best answer for each test item before the number. 1. Which of the following statement describe a continuous random variable? A. The number of students present in a Class Temperance. B. The average distance travelled by a tricycle in a month. C. The number of motorcycles owned by a randomly selected household. D. The number of girls taller than 5 feet in a random sample of 6 girls. 2. Which of the following is an example of discrete variable? A. Distance travelled between cars. C. Number of blue marbles in the box. B. Height of the students in a section. D. Weight of potatoes in the basket. 3. You decided to conduct a survey of families with two children. You are interested incounting the number of girls (out of 2 children) in each family. Is this a random variable? A. Yes, it is a random variable. C. Maybe. B. No, it is not a random variable. D. Cannot be determined. 4. Suppose you tossed three coins. What are the sample spaces for the experiment above? A. HHH, TTT C. TTT, HHH, TTH, THT, HTH B. TTT, HHH, HHT, THT, HTH D. TTT, TTH, THT, HTT, HHT, HTH, THH, HHH 5. Suppose three laptops are tested. Let D represent the defective laptop and N for the non-defective laptop. How many possible outcomes will occur from the experiment? A. 3 B. 4 C. 8 D. 9 6. Based on number 5, if we let $X$ be the random variable representing the number of non-defective laptops. What are the possible values of the random variable? A. 0,1 B. $0,1,2$ C. 1, 2, 3 D. $0,1,2,3$ 7. Which probability distribution represents the given problem on number 6? A. B. | $x$ | 0 | 1 | 2 | | :-- | :-- | :-- | :-- | | $P(x)$ | $1 / 2$ | $1 / 2$ | $1 / 4$ | | $x$ | 0 | 1 | 2 | | :-- | :-- | :-- | :-- | | $P(x)$ | $1 / 2$ | $3 / 8$ | $3 / 8$ | C. D. | $x$ | 0 | 1 | 2 | | :-- | :-- | :-- | :-- | | $P(x)$ | $1 / 4$ | $1 / 2$ | $1 / 4$ | | $x$ | 0 | 1 | 2 | 3 | | :-- | :-- | :-- | :-- | :-- | | $P(x)$ | $1 / 8$ | $1 / 8$ | $35 / 8$ | $1 / 8$ | 8. The given table represents a probability distribution. What is $P(x) \mathrm{i}^{2} x=1+4$ ? | $x$ | 4 | 8 | 16 | 16 | | :--: | :--: | :--: | :--: | :--: | | $P(x)$ | 1 | 2 | 3 | 3 |

A student entering a doctoral program in educational psychology is required to select three courses from the list of courses provided as part of his or her program. (a) List all possible three-course selections. (b) Comment on the likelihood that EPR 656, EPR 683, and EPR 689 will be selected. Click the icon to view the course list. (a) Select all the possible three-course selections below. $\square$ A. 683, 689, 606 $\square$ B. 656, 683, 689 $\square$ C. 685, 606, 685 $\square$ D. 606, 665, 606 $\square$ E. 656, 683, 685 $\square$ F. 656, 685, 689 $\square$ G. 656, 656 $\square$ H. 656, 689, 606 $\square$ I. 656, 656, 683 $\square$ J. 683, 685, 689 $\square$ K. 685, 689, 606 $\square$ L. 656, 685, 606 $\square$ M. 656, 683, 606 $\square$ N. 683, 685, 606

Which could be a conditional relative frequency table? | | **B** | **B** | **Total** | | --- | --- | --- | --- | | C | 0.25 | 0.75 | 1.0 | | D | 0.35 | 0.65 | 1.0 | | Total | 0.30 | 0.70 | 1.0 | | | A | B | Total | | C | 0.75 | 0.25 | 0.50 | | D | 0.25 | 0.75 | 0.50 | | Total | 0.50 | 0.50 | 1.0 | | | A | B | Total | | C | 0.65 | 0.35 | 1.0 | | D | 0.35 | 0.65 | 1.0 | | Total | 1.0 | 1.0 | 1.0 |

How do you find the point estimate from a confidence interval?

The dot plot shows the heights of college women. The mean is 64 inches (5 feet 4 inches) and the standard deviation is 3 inches. Complete parts a and b below. a. What is the z-score for a height of 61 inches? b. What is the height of a human with a z-score of 3?

5. An automobile manufacturer sold 30,000 new cars, one to each of 30,000 customers, in a certain year. The manufacturer was interested in investigating the proportion of the new cars that experienced a mechanical problem within the first 5,000 miles driven. (a) A list of the names and addresses of all customers who bought the new cars is available. Describe a sampling plan that could be used to obtain a simple random sample of 1,000 customers from the list. Each customer from a simple random sample of 1,000 customers who bought one of the new cars was asked whether they experienced any mechanical problems within the first 5,000 miles driven. Forty customers from the sample reported a problem. Of the 40 customers who reported a problem, 13 customers, or $32.5 \%$, reported a problem specifically with the power door locks. (b) Explain why 0.325 should not be used to estimate the population proportion of the 30,000 new cars sold that experienced a problem with the power door locks within the first 5,000 miles driven. (c) Based on the results of the sample, give a point estimate of the number of new cars sold that experienced a problem with the power door locks within the first 5,000 miles driven.

The director of health services is concerned about a possible flu outbreak at her college. She surveyed 100 randomly selected residents from the college's dormitories to see whether they had received a preventative flu shot. The results are shown below. What is the probability that a dormitory resident chosen at random from this group has had a flu shot, given that he is male? A)51/100 B)39/100 C)39/80 D)13/17

Choose the best definitions of parameter and statistic. - A statistic is a number that describes a sample and a parameter is a number that describes a population. - A statistic is a variable that describes a sample and a parameter is a variable that describes a population. - A parameter is an unknown characteristic of a group and a statistic is a known characteristic of a group. - A statistic is a number that describes a population and a parameter is a number that describes a sample. - A parameter is a number that describes a population. A statistic is a number that is used to estimate a parameter.

Which box plot represents the data set $2,4,6,8,10,12$ ?