Question

Indicate whether the following statement is true or false.

1. When estimating a confidence interval for the difference between the means of two independent populations, the pooled variance is the average of two sample variances, if the two sample sizes are equal.

2. Both the t-distribution and standard normal distribution have the same mean, but the t-distribution has a smaller standard deviation than the standard normal distribution.

3. The standard deviation of the distribution of (i.e. standard error of the mean) increases as the sample size increases.

4.In simple linear regression analysis, the problem that arises when the spread of the error term increases as the independent variable increases is called extrapolation

Answer #1

Hope this was helpful. Please leave back any comment.

True or false:
1. When constructing a confidence interval for a sample
Mean, the t distribution is appropriate whenever the sample size is
small.
2. The sampling distribution of X (X-bar) is not always
a normal distribution.
3. The reason sample variance has a divisor of n-1
rather than n is that it makes the sample standard deviation an
unbiased estimate of the population standard
deviation.
4. The error term is the difference between the actual
value of the dependent...

Find the margin of error for a 95% confidence interval for
estimating the population mean when the sample standard deviation
equals 90 with a sample size of (i) 484 and (ii) 1600
(i) Find the margin of error for a 95% confidence interval for
estimating the population mean when the sample standard deviation
equals 90 with a sample size of 484
(ii).
(ii) Find the margin of error for a 95% confidence interval
for estimating the population mean when the...

TRUE OR FALSE:
1. The sampling distribution of (X-bar) is
always a normal distribution according to the Central limit
theorem.
4. If the sampled population is a normal distribution, then the
sampling distribution of (X-bar is normal only for a
large enough sample size.
5. If p=.8 and n=50, then we can conclude that the sampling
distribution of the proportions is approximately a normal
distribution.
8. Assuming the same level of significancea, as the
sample size increases, the critical t-value...

Consider the following statements. When estimating a confidence
interval for the difference between the means of two independent
populations.
(i) The variances in both populations of variable X are assumed to
be zero.
(ii) Samples should be independently and randomly selected from
the populations.
(iii) Both samples have the same variance.
A.
Only (ii) is true.
B.
Only (i) is true.
C.
Both (i) and (iii) are true.
D.
Both (ii) and (iii) are true.

Consider the following statements. When estimating a confidence
interval for the difference between the means of two independent
populations.
(i) The variances in both populations of variable X are assumed to
be zero.
(ii) Samples should be independently and randomly selected from
the populations.
(iii) Both samples have the same variance.
A.
Only (i) is true.
B.
Only (ii) is true.
C.
Both (ii) and (iii) are true.
D.
Both (i) and (iii) are true.

Consider the following statements. When estimating a confidence
interval for the difference between the means of two independent
populations. (i) The variances in both populations of variable X
are assumed to be zero. (ii) Samples should be independently and
randomly selected from the populations. (iii) Both samples have the
same variance. A. Only (ii) is true. B. Only (i) is true. C. Both
(ii) and (iii) are true. D. Both (i) and (iii) are true.

True or False
6. T F The confidence interval for the average of a number of
future observations at a given value of the independent variable
increases as the number of those future observations increases.
7. T F When you can accept a relatively large error in not
rejecting a true hypothesis, you make the desirable condition the
alternative hypothesis
8. T F The experimenter cannot control the independent variable
at all times.
9. T F Decreasing the standard deviation...

True or False?
1. σM equals the standard deviation
divided by the square root of the sample size
2. Larger samples more accurately reflect the population than
smaller samples
3. If n = 1, the standard error will equal the standard
deviation of the population
4. If a population is skewed, the distribution of sample means
will never be normal
5. The mean for the distribution of samples means is equal to
the mean of the population
6. As the sample...

Find the margin of error for a 95% confidence interval for
estimating the population mean when the sample standard deviation
equals
100 with a sample size of (i)484 and (ii)1521.
What is the effect of the sample size?

True or False:
A. You can perform a two-way ANOVA only when the sample
sizes are the same in all cells.
B. When interaction is present in a two-way ANOVA, the
main effects are always uninformative.
C. ANOVA assumes that the populations are Normal with
possibly different means and the same standard deviation and that
independent simple random samples are drawn from each
population.
D. ANOVA separates the total variation into parts of the
model and error. The model variation...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 36 minutes ago

asked 51 minutes ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 3 hours ago

asked 3 hours ago

asked 4 hours ago

asked 4 hours ago

asked 4 hours ago

asked 4 hours ago

asked 4 hours ago