Concept explainers
Videos
a.
Check whether who takes out the trash is random.
a.
Answer to Problem 1E
Yes, the person who takes out the trash is random.
Explanation of Solution
A coin is flipped to decide who takes out the trash.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular outcome is not possible, then that particular outcome is said to be random.
Here, the experimenter flips a coin to decide who takes out the trash. It is not possible to predict the outcome of a coin when it is tossed. It might be either head or tail.
The experimenter flips a coin and selects a person based on the outcome of the coin. Here, the investigator might select a person if the tossed coin shows head or select a person if the tossed coin shows tail. The outcome of the tossed coin (Either head or tail) is purely random. Thus, a person is randomlyselected to decide the person who takes out the trash according to the outcome.
Hence, the experimenter implements the randomization by randomly assigninga person to take out the trash.
Thus, the person who takes out the trash is random.
b.
Check whether the sports team named by the friend is random.
b.
Answer to Problem 1E
No, the sports team named by the friend is not random.
Explanation of Solution
A sports team is named by asking a friend to quickly name a professional sports team.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular is outcome is not possible, then that particular outcome is said to be random.
Here, the sports team is named by asking a friend to quickly name a professional sports team.
The experimenter selects a sports team by asking a friend to quickly name a professional sports team.
Since, a friend knows likes and dislikes of his friendand he might guess the name of the sports team which his friend is about to give. Therefore, the spots team named by friend is predictable. Thus, a sports team named by the friend is not randomly selected.
Hence, the experimenter does not implement randomization.
Thus, the sports team named by friendis not named at random.
c.
Check whether the roommate for the year is random.
c.
Answer to Problem 1E
Yes, the roommate for the year is random.
Explanation of Solution
Names are selected out of a hat to decide roommates in a dormitory.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular is outcome is not possible, then that particular outcome is said to be random.
Here, the experimenter selected the roommates in a dormitory by selecting names out of a hat.
The experimenter selects a name out of a hat and decides the roommate based on the outcome of the hat. The names of the roommates in a dormitory which are about to pick by the experimenter is not predictable. Thus, name of roommates in a dormitory is randomly selected by the experimenter.
Hence, the experimenter implements the randomization by randomly selecting the roommate name.
Thus, the roommate for the year is random.
Want to see more full solutions like this?
Chapter 10 Solutions
STATS:DATA+MODELS-W/DVD
- Show that L′(θ) = Cθ394(1 −2θ)604(395 −2000θ).arrow_forwarda) Let X and Y be independent random variables both with the same mean µ=0. Define a new random variable W = aX +bY, where a and b are constants. (i) Obtain an expression for E(W).arrow_forwardThe table below shows the estimated effects for a logistic regression model with squamous cell esophageal cancer (Y = 1, yes; Y = 0, no) as the response. Smoking status (S) equals 1 for at least one pack per day and 0 otherwise, alcohol consumption (A) equals the average number of alcohoic drinks consumed per day, and race (R) equals 1 for blacks and 0 for whites. Variable Effect (β) P-value Intercept -7.00 <0.01 Alcohol use 0.10 0.03 Smoking 1.20 <0.01 Race 0.30 0.02 Race × smoking 0.20 0.04 Write-out the prediction equation (i.e., the logistic regression model) when R = 0 and again when R = 1. Find the fitted Y S conditional odds ratio in each case. Next, write-out the logistic regression model when S = 0 and again when S = 1. Find the fitted Y R conditional odds ratio in each case.arrow_forward
- The chi-squared goodness-of-fit test can be used to test if data comes from a specific continuous distribution by binning the data to make it categorical. Using the OpenIntro Statistics county_complete dataset, test the hypothesis that the persons_per_household 2019 values come from a normal distribution with mean and standard deviation equal to that variable's mean and standard deviation. Use signficance level a = 0.01. In your solution you should 1. Formulate the hypotheses 2. Fill in this table Range (-⁰⁰, 2.34] (2.34, 2.81] (2.81, 3.27] (3.27,00) Observed 802 Expected 854.2 The first row has been filled in. That should give you a hint for how to calculate the expected frequencies. Remember that the expected frequencies are calculated under the assumption that the null hypothesis is true. FYI, the bounderies for each range were obtained using JASP's drag-and-drop cut function with 8 levels. Then some of the groups were merged. 3. Check any conditions required by the chi-squared…arrow_forwardSuppose that you want to estimate the mean monthly gross income of all households in your local community. You decide to estimate this population parameter by calling 150 randomly selected residents and asking each individual to report the household’s monthly income. Assume that you use the local phone directory as the frame in selecting the households to be included in your sample. What are some possible sources of error that might arise in your effort to estimate the population mean?arrow_forwardFor the distribution shown, match the letter to the measure of central tendency. A B C C Drag each of the letters into the appropriate measure of central tendency. Mean C Median A Mode Barrow_forward
- A physician who has a group of 38 female patients aged 18 to 24 on a special diet wishes to estimate the effect of the diet on total serum cholesterol. For this group, their average serum cholesterol is 188.4 (measured in mg/100mL). Suppose that the total serum cholesterol measurements are normally distributed with standard deviation of 40.7. (a) Find a 95% confidence interval of the mean serum cholesterol of patients on the special diet.arrow_forwardThe accompanying data represent the weights (in grams) of a simple random sample of 10 M&M plain candies. Determine the shape of the distribution of weights of M&Ms by drawing a frequency histogram. Find the mean and median. Which measure of central tendency better describes the weight of a plain M&M? Click the icon to view the candy weight data. Draw a frequency histogram. Choose the correct graph below. ○ A. ○ C. Frequency Weight of Plain M and Ms 0.78 0.84 Frequency OONAG 0.78 B. 0.9 0.96 Weight (grams) Weight of Plain M and Ms 0.84 0.9 0.96 Weight (grams) ○ D. Candy Weights 0.85 0.79 0.85 0.89 0.94 0.86 0.91 0.86 0.87 0.87 - Frequency ☑ Frequency 67200 0.78 → Weight of Plain M and Ms 0.9 0.96 0.84 Weight (grams) Weight of Plain M and Ms 0.78 0.84 Weight (grams) 0.9 0.96 →arrow_forwardThe acidity or alkalinity of a solution is measured using pH. A pH less than 7 is acidic; a pH greater than 7 is alkaline. The accompanying data represent the pH in samples of bottled water and tap water. Complete parts (a) and (b). Click the icon to view the data table. (a) Determine the mean, median, and mode pH for each type of water. Comment on the differences between the two water types. Select the correct choice below and fill in any answer boxes in your choice. A. For tap water, the mean pH is (Round to three decimal places as needed.) B. The mean does not exist. Data table Тар 7.64 7.45 7.45 7.10 7.46 7.50 7.68 7.69 7.56 7.46 7.52 7.46 5.15 5.09 5.31 5.20 4.78 5.23 Bottled 5.52 5.31 5.13 5.31 5.21 5.24 - ☑arrow_forward
- く Chapter 5-Section 1 Homework X MindTap - Cengage Learning x + C webassign.net/web/Student/Assignment-Responses/submit?pos=3&dep=36701632&tags=autosave #question3874894_3 M Gmail 品 YouTube Maps 5. [-/20 Points] DETAILS MY NOTES BBUNDERSTAT12 5.1.020. ☆ B Verify it's you Finish update: All Bookmarks PRACTICE ANOTHER A computer repair shop has two work centers. The first center examines the computer to see what is wrong, and the second center repairs the computer. Let x₁ and x2 be random variables representing the lengths of time in minutes to examine a computer (✗₁) and to repair a computer (x2). Assume x and x, are independent random variables. Long-term history has shown the following times. 01 Examine computer, x₁₁ = 29.6 minutes; σ₁ = 8.1 minutes Repair computer, X2: μ₂ = 92.5 minutes; σ2 = 14.5 minutes (a) Let W = x₁ + x2 be a random variable representing the total time to examine and repair the computer. Compute the mean, variance, and standard deviation of W. (Round your answers…arrow_forwardThe acidity or alkalinity of a solution is measured using pH. A pH less than 7 is acidic; a pH greater than 7 is alkaline. The accompanying data represent the pH in samples of bottled water and tap water. Complete parts (a) and (b). Click the icon to view the data table. (a) Determine the mean, median, and mode pH for each type of water. Comment on the differences between the two water types. Select the correct choice below and fill in any answer boxes in your choice. A. For tap water, the mean pH is (Round to three decimal places as needed.) B. The mean does not exist. Data table Тар Bottled 7.64 7.45 7.46 7.50 7.68 7.45 7.10 7.56 7.46 7.52 5.15 5.09 5.31 5.20 4.78 5.52 5.31 5.13 5.31 5.21 7.69 7.46 5.23 5.24 Print Done - ☑arrow_forwardThe median for the given set of six ordered data values is 29.5. 9 12 23 41 49 What is the missing value? The missing value is ☐.arrow_forward
MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSON
The Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. Freeman
Introduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman