Liberty University - EDCO 735/EDCO735 Week 2 Quiz
A two-tailed outlier for the t distribution must have a t score equivalent to the: highest 5% or lowest ... [Show More] 5% of
the t distribution
only the highest 5% of the t distribution
only the lowest 5% of the t distribution
highest 2.5% or lowest 2.5% of the t distribution
In order to calculate the mean you must: multiply each score by itself
take the square root of the sum
have at least interval level of measurement
divide by degrees of freedom
Response Feedback:
Warner - Section 2.3
Outliers in the sample are defined by: a measure of dispersion
how far any given score in the population can be expected to be from the mean
how many standard deviations there score is from the mean the square root of variance
The t distribution and the z distribution: are skewed
have 95% confidence level
have values associated with percentiles
are random
1.5 Calculating the sample standard deviation always makes use of:
nominal level of measurement
variance convenience sample random sample
Known distributions (e.g., t, z, and F) allow us: determine causal inference
determine the percentile of our score or statistic
give and receive scores label our means
Which of the following is needed to calculate confidence interval's upper limit? population
mean
SS
variance
2.6 Which of the following is needed to calculate confidence interval's upper limit?
SEM SS
each score value
Sampling error:
depends on sample size
is large when we have a diverse population
is the s
is smaller the more educated the sample
For every statistic (e.g., mean) a researcher calculates in her sample, she is estimating that same value in the:
second sample distribution population
experimental sample
In order to calculate the mean you must:
divide by the sample size use a representative sample
have at least ratio level of measurement
have a normal distribution
7.5 A one-tailed outlier for the t distribution must have a t score equivalent to the:
only the lowest 5% of the t distribution
highest 5% or lowest 5% of the t distribution
only the highest 5% of the t distribution
highest 2.5% or lowest 2.5% of the t distribution
Response Feedback:
Warner - Section 2.13
4.4 When different sets of data of the same size are randomly chosen from a population, the resulting variation in values is called:
standard deviation
sampling error
confidence interval
magnitude of error
3.5 In order to calculate variance you must do all of the following except for:
multiply the difference between each score and the mean by itself
Response Feedback:
divide the sum of squared deviations by the sample size ??
compute the mean
subtract the mean from each score Warner - Sections 2.4 - 2.6
3.4 degrees of freedom
is the square root of variance
is calculated by subtracting one from the sample size
is calculated by dividing the SS by the mean
is calculated by dividing the SS by the sample size
In order to calculate variance you must:
divide the sum of squared deviations by n divide the sum of squared deviations by df
take the square-root of the sum of squared deviations
divide the sum of scores by df
Response Feedback:
Warner - Section
2.4-2.6
In study of a new treatment for depression, a researcher compares the new treatment on a group of patients with major depression with a second group that are treated with the standard treatment as usual. How many theoretical populations is the researcher estimating depression for?
one two none three
Response Feedback:
It is important to note that before treatment each group in an experimental study is equivalent. After treatment, however, each group that is treated uniquely represents a different theoretical population.
We estimate error because:
Response Feedback:
it helps understand the relationship between our sample and the population
our population is hypothetical it effects the standard deviation its conventional to do so Warner - Section 2.11 - 2.14
6.5 How do researchers report information about the size of sampling error?
using a confidence interval
Response Feedback:
magnitude of the difference
random sample standard error Warner - 2.8-2.14
The difference between the population mean and the sample mean that arise just by chance represents the:
magnitude of the difference
sampling error ?? 6 standard error prediction error
Response Feedback:
Warner - Section 2.10
In a study of a new drug intended to reduce anxiety, a researcher has a low dose group, a medium dose group, and a placebo control group. How many theoretical populations are represented in this study?
thre e
one two four
Sampling error refers to:
about how much we should expect an individual score in our sample to be from the population mean
about how much we should expect our sample mean to be from the population mean
the amount of error in our measurement how representative our sample is
Response Feedback:
Warner - Section 2.8 - 2.14
The t distribution and the z distribution are: symmetric
al
leptokurti c
random biased
Response Feedback:
Warner - Section 2.8 - 2.14
3.6 All of the following calculations are necessary for calculating s except for:
t critical variance
mean
sum of squared deviations
1.6 s is all of the following except: is a measure of dispersion
is the square root of variance
tells us about how far any given score in the population can be expected to be from the mean
is biased
Response Feedback:
Warner - Section 2.4
- 2.6
The formula for a confidence interval's upper limit is:
s +
[tcritical × SEM] s -
[tcritical × SEM]
M -
[tcritical × SEM] M +
[tcritical × SEM]
In words, what is the formula for the SEM?
the standard deviation multiplied by the square root of the sample size
the sample mean multiplied by the square root of the sample size
the standard deviation divided by the square root of the sample size
the sample mean divided by the square root of the sample size
The distribution of depression scores in the theoretical population is NOT:
Gaussian platykurtic
symmetric al
bell- shaped
Response Feedback:
The distribution of a quantitative variable in a theoretical population is always assumed to be normal.
8.4 Which of the following is NOT one of the steps for calculating a confidence interval?
determine df
calculate the F ratio
determine tcritical
calculate the SEM
What information do you need to find tcritical for a 95% CI?
df
M SE
M
s
6.6 The variations of the t distribution are especially noticeable when: the population is
normal
the sample is biased
sample sizes are small
the sample is normal
Response Feedback:
Warren - Section 2.13
As N increases, the standard error of the mean:
varies randomly
increases
remains constant
decreases
2.5 A two-tailed outlier for the Z distribution must have a Z score equivalent to the: only the lowest 5% of the z distribution
only the highest 5% of the z distribution
highest 5% or lowest 5% of the z distribution
highest 2.5% or lowest 2.5% of the z distribution
2.4 The theoretical population is:
the population that a particular statistic estimates
only matters when a convenience sample
is used
the population where both groups are drawn
equivalent to the population of the world
The standard error of the mean is conceptually similar to:
causal inference
the standard deviation
variance
sum of squared deviations
Response Feedback:
Warner - 2.11
9.6 The t distribution and the z distribution are all of the following all of the time except:
platykurtic
discovered or developed by statisticians
have values associated with percentiles
symmetrical
Sum of squared deviations:
can never be negative has no lower limit
is divided by the sample size to calculate variance
can never be zero
Variance:
is calculated by dividing the SS by the sample size is biased when calculated by df
is a measure of dispersion
tells us about how far any given score in the population can be expected to be from the mean
7.4 df are used because:
samples underestimate population variance
sample distributions are skewed
samples underestimate SS samples provide the point estimate
The t distribution and the z distribution are all of the following all of the time except: map to percentiles
discovered or developed by statisticians
normal symmetrical
The larger the sample size: the more sampling error
the less random our sample the less sampling error
the more outliers influence our distribution
6.4 z and t distributions are known because: statisticians developed\discovered
them
they measure variance
Karl Pearson developed them they have always been
What is the formula for the df of a CI?
M - 1
s - 1
n - 1
SEM - 1
• Question 7
All of the following calculations are necessary for calculating s except for:
• Question 8
The theoretical population is:
Response Feedback:
Warner - Section 2.10 - 2.14
• Question 5
What is the formula for the df of a CI?
• Question 2
5.4 As sample size increases while all other things are constant, the confidence interval:
decreases
Response Feedback:
Warner - Section 2.9- 2-14
• Question 3
10.5 Which of the following is NOT needed in the formula for calculating a confidence interval's lower limit?
M
• Question 3
The standard error is related to all of the following except:
1.4 The standard error is related to all of the following except: - causal inference
10. 4 t critical when the population is:
Known
5.5 Which of the following is needed to calculate confidence interval’s lower limit? -SEm
SS
M
Which of the following is needed to calculate confidence interval's lower limit?
SEm
4.5 As N decreases we can expect the standard error of the mean to:
Increases
9.4 In order to calculate the sum of squared deviations you must
take the square root of the sum
4.6 In order to calculate the sum of squared deviations you must do all of the following except for:
Calculate square root of variance
7.6 Outliers are defined by:
where the scores or values fall on a known (t, z, F) distribution
8.6 A statistic of the sample is an estimate of: the parameter in the second sample
the statistic in the second sample
the parameter in the theoretical sample
10.6 The theoretical population can also be conceptualized as the:
the population that a particular statistic estimates
A one-tailed outlier for the Z distribution must have a Z score equivalent to the:
the highest 5% of the z distribution only
Which of the following is NOT needed in the formula for calculating a confidence interval's upper limit?
SEm M
We use a t critical when the population is:
known Theoretical
Variance
is biased when calculated by df
The mean of a sample is:
the average of all scores divided by the sample size [Show Less]
