| № |
Condition |
free/or 0.5$ |
| m304 | Compute the mean and variance of the following discrete probability distribution.
x P(x)
2 ...... .5
8 ...... .3
10 ...... .2 |
buy |
| m305 | Compute the mean and variance of the following probability distribution.
x P(x)
5 ....... .1
10 ....... .3
15 ....... .2
20 ....... .4 |
buy |
| m306 | Computer keyboard failures are due to faulty electrical connects (12%) or mechanical defects (88%). Mechanical defects are related to loose keys (27%) or improper assembly (73%). Electrical connect defects are caused by defective wires (35%), improper connections (13%), or poorly welded wires (52%). (a) Find the probability that a failure is due to loose keys.
(b) Find the probability that a failure is due to improperly connected or poorly welded wires. |
buy |
| m307 | Computers in a shipment of 100 units contain a portable hard drive, CD RW drive, or both according to the following table:
Portable hard drive
Yes No
CD RW
Yes 15 80
No 4 1
Let A denote the events that a computer has a portable hard drive and let B denote the event that a computer has a CD RW drive. If one computer is selected randomly,
compute (a) P (A)
(b) P (A ∩ B)
(c) P (A U B)
(d) P (A’ ∩ B)
(e) P (A|B) |
|
| m308 | A large manufacturing firm is being charged with discrimination in its hiring practices.
(a) What hypothesis is being tested if a jury commits a type I error by dueling the firm guilty?
(b) What hypothesis is being tested if a jury commits a type II error by finding the firmguilty? |
buy |
| m309 | Repeat Exercise 10.8 when 100 spots are treated and the critical region is defined to be x > 82, where x is the number of spots removed. |
buy |
| m310 | A new curve has been developed for a certain type of cement that results in a compressive strength of 5000 kilograms per square centimeter and a standard deviation of 120. To test the hypothesis that μ = 5000 against the alternative that p < 5000, a random sample of 50 pieces of cement is tested. The critical region is defined to be x < 4970.
(a) Find the probability of committing a type error when H n is true.
(b) Evaluate 0 for the alternatives p = 4970 and p = 1960. |
buy |
| m311 | A manufacturer has developed a new fishing line, which he claims has a mean breaking strength of 15 kilograms with a standard deviation of 0.5 kilogram. To test the hypothesis that, p = 15 kilograms against the alternative that p < 15 kilograms, a random sample of 50 lines will be tested. The critical region is defined to be x < 14.9.
(a) Find the probability of committing a type I error when Ha is true.
(b) Evaluate 8 for the alternatives p — 14.8 and p = 14.9 kilograms. |
buy |
| m312 | Consider a sequence of independent Bernoulli trials with p _ 0.2.
(a) What is the expected number of trials to obtain the first success?
(b) After the eighth success occurs, what is the expected number of trials to obtain the ninth success? |
|
| m313 | Consider the ANOVA table that follows.
a. Determine the standard error of estimate. About 95% of the residuals will be between what two values?
b. Determine the coefficient of multiple determination. Interpret this value.
c. Determine the coefficient of multiple determination, adjusted for the degrees offreedom. |
|
| m314 | Consider the ANOVA table that follows.
a. Determine the standard error of estimate. About 95% of the residuals will be between what two values?
b. Determine the coefficient of multiple determination. Interpret this value.
c. Determine the coefficient of multiple determination, adjusted for the degrees offreedom. |
buy |
| m315 | Consider the data in Exercise 10 from Chapter 14 and the regression equation to predict commissions earned.
a. Plot the residuals in the order in which the data are presented.
b. Test for autocorrelation at the .01 significance level. |
|
| m316 | Consider the data on wafer contamination and location in the sputtering tool shown in Table 2-2. Assume that one wafer is selected at random from this set. Let A denote the event that a wafer contains four or more particles, and let B denote the event that a wafer is from the center of the sputtering tool. Determine:
(a) P (A)
(b) P (A|B)
(c) P (B)
(d) P (B|C)
(e) P (A ∩ B)
(f) P (A U B) |
|
| m317 | Consider the following chart.
a. What is this chart called?
b. How many observations are in the study?
c. What are the maximum and the minimum values?
d. Around what values do the observations tend tocluster? |
|
| m318 | Consider the following partially completed two-way ANOVA table. Suppose there are four levels of Factor A and three levels of Factor B. The number of replications per cell is 5. Complete the table and test to determine if there is a significant difference in Factor A means, Factor B means, or the interaction means. Use the .05 significance level. |
buy |
| m319 | Consider the following sample data for a two-factor ANOVA analysis. There are two levels (heavy and light) of factor A (weight), and three levels (small, medium, and large) of factor B (size). For each combination of size and weight, there are three observations.
Compute an ANOVA with statistical software, and use the .05 significance level to answer the following questions.
a. Is there a difference in the Size means?
b. Is there a difference in the Weight means?
c. Is there a significant interaction between Weight andSize? |
buy |
| m320 | Consider the variable mean amount per transaction in the Home Depot data presented above. This variable indicates, for example, that the average customer spent $39.13 on goods during a store visit in 1993. By 2012 this amount increased to $54.89. During that same period the Consumer Price Index (CPI) as reported by the Bureau of Labor Statistics increased from 144.5 to 229.594. Convert the CPI to a 1993 base, as described on page 640 in the previous chapter, and convert the mean amount per transaction to 1993 dollars. Develop a linear trend equation for the constant 1993 dollars of the mean amount per transaction. Is it reasonable that the trend is linear? Can we conclude that the value of the amount the customer spent is less? |
buy |
| m321 | Consider these five values a population: 8, 3, 7, 3, and 4.
a. Determine the mean of the population.
b. Determine the variance. |
|
| m322 | Consider these six values a population: 13, 3, 8, 10, 8, and 6.
a. Determine the mean of the population.
b. Determine the variance. |
|
| m323 | Consider these values a sample: 7, 2, 6, 2, and 3.
a. Compute the sample variance.
b. Determine the sample standard deviation. |
|
