____, in APA format, means the null hypothesis was not rejected.
If one fails to reject the null hypothesis, one says there is ____ evidence to conclude that the independent variable affects the dependent variable.
If the cost of making a Type I error is high, one might set alpha at ____.
The probability of Type II error is commonly set at ____.
An article in the Journal of Testing and Evaluation (1988, Vol. 16, pp. 508515) investigated the effects of cyclic loading frequency and environment conditions on fatigue crack growth at a constant...
The mean vacancy rate for apartment rentals in the United States is 10% with a standard deviation of 4.6. An urban studies major obtained a sample of 15 rustbelt cities and found that the mean...
The percentage of hardwood concentration in raw pulp, the freeness, and the cooking time of the pulp are being investigated for their effects on the strength of paper. The data from a three-factor...
Calculate z for M = 97, = 85, and M = 4.5
Given N = 87 and z = 1.96, (a) Decide if the null hypothesis was rejected, and (b) Report the results in APA format. Use = .05,two-tailed.
Two sample t tests compare the ____ of one sample to the ____ of another sample.
A classic experiment might use a two-sample t test to compare a ____ group to an ____ group.
If each sample in a two-sample t test is a random sample from its population, then the test is an ____-samples t test.
____ is the abbreviation for the total sample size in an independent-samples t test; ____ and ____ are the abbreviations for the sizes of the samples in the two groups.
The nonrobust assumption for an independent- samples t test is ____.
One tests the ____ assumption for the independent- samples t test by comparing the ____ of the two samples.
The null hypothesis for a two-tailed independent- samples t test, expressed mathematically, is ____.
If the null hypothesis for an independent-samples t test is true, then the observed difference between the sample means is due to ____.
t tests commonly are ____ tailed and have ____ set at .05.
To calculate s M1M2 , one needs to know the sample ____ and the sample ____.
If a researcher rejects the ____, the researcher is forced to accept the ____.
If one rejects the null hypothesis for an independent- samples t test, then look at the sample ____ in order to comment on the ____ of the difference.
If the result of an independent-samples t test is written as t(23) = 5.98, p < .05, then N was ____.
For an independent-samples t test, calculate ____ to quantify the size of the effect.
A d of ____ is considered a medium effect.
An article in the IEEE Transactions on Components, Hybrids, and Manufacturing Technology (1992, Vol. 15) described an experiment for aligning optical chips onto circuit boards. The method involves...
If the 95% confidence interval for the difference between population means fails to capture zero for a two-tailed test with = .05, then one has ____ the null hypothesis.
An article in the Journal of Quality Technology (1985, Vol. 17, pp. 198206) described the use of a replicated fractional factorial to investigate the effect of five factors on the free height of leaf...
If the 95% confidence interval for the difference between population means comes close to zero, the size of the effect in the population may be ____.
Given M 1 = 88, M 2 = 83, t cv = 2.042, t = 2.040, and a two-tailed test with = .05, (a) Decide whether the null hypothesis was rejected or not, (b) Tell whether the difference between sample means...
If n 1 = 17 and n 2 = 18, determine the critical value of t for an independent-samples t test, two-tailed, = .05.
Cohens d, when calculated for a paired-samples t test, includes the effect of ____ as well as the effect of the independent variable on the ____.
Determine the covariance and correlation for the CD4 counts in a month and the following month in Exercise 5-30. Exercise 5-30 An article in Health Economics [Estimation of the Transition Matrix of a...
Using the data on bridge conditions from Exercise 6-20, (a) Find the quartiles and median of the data. (b) Draw a box plot for the data. (c) Should any points be considered potential outliers?...
As treatment has an impact on outcome, the value of the F ratio climbs above ____.
If treatment has ____ impact on outcome, the sample means are close together.
The number of categories of an independent variable in ANOVA are called ____.
Researchers in the Hopkins Forest (see Exercise 7-16) also count the number of maple trees (genus acer) in plots throughout the forest. The following is a histogram of the number of live maples in...
If F cv = 3.238, draw a sampling distribution of F, label the rare and common zones, locate F = 1.96, and determine, for this F value, if the null hypothesis should be rejected.
Let X 1 and X 2 be independent random variables with mean μ and variance Ï 2 . Suppose that we have two estimators of μ: (a) Are both estimators unbiased estimators...
Complete this ANOVA summary table: Sum of Degrees of Source of Mean Variability Squares Square Fratio Freedom Between 172.80 2 groups Within 6,410.80 12 groups Total 6,583.60 14
If SS Between = 138.76 and df Between = 4, what is MS Between ?
Dairy cows at large commercial farms often receive injections of bST (Bovine Somatotropin), a hormone used to spur milk production. Bauman et al. (Journal of Dairy Science, 1989) reported that 12...
Cohen considers an r 2 of 9% to be a ____ effect.
If the null hypothesis is not rejected, ANOVA results are reported in APA format as p ____ .05.
If F cv = 2.486 and F = 1.98, is the null hypothesis rejected?
State the null and alternative hypothesis in each case. (a) A hypothesis test will be used to potentially provide evidence that the population mean is more than 10. (b) A hypothesis test will be used...
Within-subjects, one-way ANOVA is like between-subjects, one-way ANOVA but is for ____ samples.
A hypothesis will be used to test that a population mean equals 10 against the alternative that the population mean is more than 10 with known variance . What is the critical value for the test...
If cases within a sample influence each others scores on the dependent variable, then the ____ assumption is ____.
The abbreviation for the critical value of F is ____.
If the conclusion of a repeated-measures ANOVA is that there is no evidence of a difference among population means, then the null hypothesis was / was not rejected.
df ____ and df ____ are not needed to find F cv for a one-way, repeated-measures ANOVA.
To calculate N, one multiplies together ____ and ____.
If one knows that the null hypothesis for a one-way, repeated-measures ANOVA was rejected, one does / does not know which pairs of sample means had statistically significant differences.
An article in the British Medical Journal [Comparison of Treatment of Renal Calculi by Operative Surgery, Percutaneous Nephrolithotomy, and Extracorporeal Shock Wave Lithotripsy (1986, Vol. 292, pp....
If a researcher suggests replication with a larger sample size, then he or she is probably worried about Type ____ error.
Given = .05, df Treatment = 3, df Residual = 24, F = 2.76, and F cv = 3.009, (a) Write the results in APA format, and (b) State if the results are statistically significant or not.
Setting the decision rule for one-way, repeated-measures ANOVA. (Assume = .05.) Given df Treatment = 3 and df Residual = 36, (a) What is F cv ? (b) Draw the sampling distribution of F, being sure to...
First-year college students were surveyed about how much they liked their roommates (a) Within five minutes of meeting them, (b) After the first week of classes, and (c) At the end of the semester....
Consider the hypothesis test H 0 : 2 1 = 2 2 against H 1 : 2 1 2 2 . Suppose that the sample sizes are n 1 = 15 and n 2 = 15, and the sample variances are s 2 1 = 2.3 and s 2 2 = 1.9. Use =...
Given R = 2, C = 4, n = 12, SS Rows = 78.00, SS Columns = 23.00, SS Interaction = 124.00, and SS Within = 350.00, complete the ANOVA summary table for a between-subjects, two-way ANOVA.
Two different types of injection-molding machines are used to form plastic parts. A part is considered defective if it has excessive shrinkage or is discolored. Two random samples, each of size 300,...
An article in the Journal of the American Statistical Association [Markov Chain Monte Carlo Methods for Computing Bayes Factors: A Comparative Review (2001, Vol. 96, pp. 11221132)] analyzed the...
A study was conducted attempting to relate home ownership to family income. Twenty households were selected and family income was estimated along with information concerning home ownership (y = 1...
Exercise 11.1 described a regression model between percent of body fat (%BF) as measured by immersion and BMI from a study on 250 male subjects. The researchers also measured 13 physical...
To qualify for a medical study, an applicant must have a systolic blood pressure in the 50% of the middle range. If the systolic blood pressure is normally distributed with a mean of 120 and a...
An article in IEEE Transactions on Instrumentation and Measurement (2001, Vol. 50, pp. 20332040) reported on a study that had analyzed powdered mixtures of coal and limestone for permittivity. The...
An article in Optical Engineering [Operating Curve Extraction of a Correlators Filter (2004, Vol. 43, pp. 27752779)] reported on the use of an optical correlator to perform an experiment by varying...
The average salary for graduates entering the actuarial field is $63,000. If the salaries are normally distributed with a standard deviation of $5000, find the probability that a. An individual...
For a certain group of individuals, the average heart rate is 72 beats per minute. Assume the variable is normally distributed and the standard deviation is 3 beats per minute. If a subject is...
Consider the regression model fit to the X-ray inspection data in Exercise 12-15. Use rads as the response. (a) Test for significance of regression using = 0.05. What is the P-value for this test?...
A survey of 1000 U.S. adults found that 33% of people said that they would get no work done on Cyber Monday since they would spend all day shopping online. Find the 95% confidence interval of the...
Consider the regression model fit to the stack loss data in Exercise 12-20. Use stack loss as the response. (a) Test for significance of regression using α = 0.05. What is the P-value...
The number of calories per candy bar for a random sample of standard-size candy bars is shown below. Estimate the mean number of calories per candy bar with 98% confidence. Assume that all variables...
A random sample of 50 cars in the drive-thru of a popular fast food restaurant revealed an average bill of $18.21 per car. The population standard deviation is $5.92. Estimate the mean bill for all...
If z r = 0.87 and s r = .08, what is the 95% confidence interval for in z r units?
Writing APA format with = .05, two-tailed. Given df = 87 and r = .18, write the results in APA format.
If r cv = .200, draw the sampling distribution of r and label the rare and common zones.
Given a one-tailed test, = .05, N =33, and H 1 : > 0, what is r cv ?
Given a two-tailed test with = .05 and df = 27, what is r cv ?
Consider the stack loss data in Exercise 12-20. Build regression models for the data using the following techniques: (a) All possible regressions. (b) Stepwise regression. (c) Forward selection. (d)...
The strength of relationship, in a scatterplot, is determined by how well the points form a ____.
Measures of ____ quantify the degree of relationship between two variables.
Suppose that two variables, X and Y, are negatively associated. Does this mean that above-average values of X will always be associated with below-average values of Y? Explain.
Consider the diameter data in Exercise 15-75. Assume that the desired process target is 10.0 millimeters. (a) Estimate the process standard deviation. (b) Construct an EWMA control chart with...
A ____ slope means the line is moving down and to the right.
Match each of the given differential equations with one or more of these solutions: (a) y = 0, (b) y = 2, (c) y = 2x, (d) y = 2x 2 . 1. xy' = 2y 2. y' = 2 3. y' = 2y 4 4. xy' = y 5. y'' + 9y = 18 6....
In the linear regression equation, b is the ____ and a is the ____.
At some vacation destinations, all-inclusive resorts allow you to pay a flat rate and then eat and drink as much as you want. There has been concern about whether these deals might lead to excessive...
What type of variable is required to construct a confidence interval for a population proportion?
The null and alternative hypotheses are given. Determine whether the hypothesis test is left-tailed, right-tailed, or two tailed. What parameter is being tested? H 0 : = 4.2 H 1 : 4.2
The null and alternative hypotheses are given. Determine whether the hypothesis test is left-tailed, right-tailed, or two tailed. What parameter is being tested? H 0 : = 120 H 1 : < 120
You are bidding on four items available on eBay. You think that for each bid, you have a 25% chance of winning it, and the outcomes of the four bids are independent events. Let X denote the number of...
The variance of a probability distribution of a random variable is a weighted average of its squared distances from the mean m. For discrete random variables, it equals Ï 2 = Σ(x -...
Solely on the basis of the physical description of the mixture problem on page 108 and in the following figure, discuss the nature of the functions x 1 (t) and x 2 (t). What is the behavior of each...
A random sample of 30 large companies in the United States shows the amount, in millions of dollars, that each company donated to charity for a specific year. Construct a frequency distribution for...
Approximately 70% of the U.S. population recycles. According to a green survey of a random sample of 250 college students, 204 said that they recycled. At = 0.01, is there sufficient evidence to...
The data show the maximum wind speeds for a sample of 40 states. Find the mean and modal class for the data. Class boundaries Frequency 47.554.5 3 54.561.5 2 61.568.5 9 68.575.5 13 75.582.5 8...
The frequency distributions shown indicate the percentages of public school students in fourth-grade reading and mathematics who performed at or above the required proficiency levels for the 50...
Factory workers are constantly encouraged to practice zero tolerance when it comes to accidents in factories. Accidents can occur because the working environment or conditions themselves are unsafe....