STATISTICS BEC1
PRACTICE EXAM QUESTIONS WITH
CORRECT DETAILED ANSWERS |
ALREADY GRADED A+<RECENT
vERSION>
1) Data values that do not fit the pattern of the rest of the data are - ANSWER are
considered outliers
2) A strong correlation (>0.85) between the independent variables that you want to
include in one multivariate linear regression model is an indication that which
assumption has been violated? - ANSWER multicolinearity
3) Commonly used techniques of presenting and organizing statistical data include
which of the following? - ANSWER descriptive statistics, graphical displays and
frequency distributions
4) The set of probabilities associated with each possible outcome in the sample space is
referred to as - ANSWER probability distribution
5) A null hypothesis was not rejected, and later it was found that the results were false.
This is an example of - ANSWER type II error
6) One of the important benefits of multivariate regression over many other statistical
tests is that it - ANSWER allows you to adjust for potentially confounding
variables
,7) A research project that follows the participants forward in time to identify future
outcomes is referred to as - ANSWER cohort study
8) In a study looking at the correlation between annual income and cholesterol level, one
concern was that the age of the participants might be a confounder because both
income and cholesterol generally increase with age. Which of the following
correlation methods could the researchers use to remove the influence of age on the
correlation between income and cholesterol level? - ANSWER partial correlation
9) Statistics use distinct symbols to represent specific information. Parameters are
usually represented by - ANSWER lowercase Greek letters
10) Researchers conducting a study with ____ power have a _____ probability of
committing a type ____ error. - ANSWER low;high;II
11) The ______ of any statistical test represents the probability that the results were
obtained by chance alone. - ANSWER p-value
12) A multivariate regression model looking at the association of intraocular pressure
(mm hg) with (1) having seasonal allergies, (2) wearing contact lenses, and (3) using
eye drops found a coefficient of determination (r2) of 0.23. How would you interpret
this statistic? - ANSWER seasonal allergies, contact lens use, and eye drop use
taken together explain 23% of the variation in intraocular eye pressure.
13) The local health department is interested in determining if there is a difference in the
incidence of childhood caries among children living in rural areas drinking untreated
well water and children living in cities drinking fluorinated water. A null hypothesis
could read - ANSWER the oral health of the rural children will not differ from that
of the city children.
14) A potential mistake when interpreting the data is to reject the H0 when it is true. This
is referred to as - ANSWER a type I error
15) Compute the mean for men, women, and overall for weight loss using the following
information: - ANSWER Women: 4.5 lbs; Men: 7.25 lbs; Total 5.6 lbs
,16) Researchers articulate the expected relationships between the variables by the
_______. - ANSWER null hypothesis
17) The study plan hypotheses - ANSWER must be very specific
18) The _____ of a test is the probability that the test result and the diagnosis agree -
ANSWER efficiency.
19) In a study looking at the association of mean hours worked per day (hours) and age
(years) with body mass index (BMI), the researchers used multivariate liner
regression. The regression equation is below. What BMI would you predict from this
equation for someone age 25 years who works 45 hours per week? - ANSWER
28.1
20) Statisticians use various scales to collect and/or identify data. The following is an
example of what type of scale? - ANSWER Ordinal scale
21) One response to the nursing shortage has resulted in the recruitment of nurses with
various educational levels. The results of one research study found that the level of
nursing education is critical in caring for certain patients. Therefore, we can conclude
that - ANSWER increasing the number of nurses without concern for educational
level has serious implications for critically ill patients
22) The researcher has determined the project has an α = 0.05. This indicates all values
outside ____ will be rejected. - ANSWER 95%
23) Under which of the following conditions would you need to use the Spearman
correlation coefficient and not the Pearson correlation coefficient? - ANSWER
One variable on the ordinal measurement scale and one is on the interval
measurement scale.
Neither variable is normally distributed.
There are only three outliers.
The two variables do not have a linear relationship.
, 24) Confidence intervals can be computed around the population mean from a single
simple mean using the - ANSWER central limit theorem
25) The alpha-level is defined by the researcher before any statistical tests are conducted.
This specific level is defined as - ANSWER statistically significant
26) Researchers rely on ________ to assist them in drawing meaningful conclusions on
data collected on a population through their research project. - ANSWER the
probability theory
27) The probability that the laboratory test is positive when given to a group of patients
who have the disease is referred to as - ANSWER sensitivity.
28) A study looking at the correlation between cholesterol level and distance between
home and work found a correlation coefficient of -0.13. How much of the variance in
cholesterol level is explained by distance between home and work (ie, what is the
coefficient of determination)? - ANSWER 1.7%
29) The first step to deciding which statistical technique to use is - ANSWER to
identify the question to be answered
30) Parts to Describing a Distribution - ANSWER Shape, outliers, center, variability
(SOCV)
31) Outlier Rule - ANSWER Any value more than 1.5IQR above Q3 or below Q1
32) Mean - ANSWER Average value of a distribution
33) Median - ANSWER Middle value of a distribution
34) Standard Deviation - ANSWER Typical distance of values from the mean
PRACTICE EXAM QUESTIONS WITH
CORRECT DETAILED ANSWERS |
ALREADY GRADED A+<RECENT
vERSION>
1) Data values that do not fit the pattern of the rest of the data are - ANSWER are
considered outliers
2) A strong correlation (>0.85) between the independent variables that you want to
include in one multivariate linear regression model is an indication that which
assumption has been violated? - ANSWER multicolinearity
3) Commonly used techniques of presenting and organizing statistical data include
which of the following? - ANSWER descriptive statistics, graphical displays and
frequency distributions
4) The set of probabilities associated with each possible outcome in the sample space is
referred to as - ANSWER probability distribution
5) A null hypothesis was not rejected, and later it was found that the results were false.
This is an example of - ANSWER type II error
6) One of the important benefits of multivariate regression over many other statistical
tests is that it - ANSWER allows you to adjust for potentially confounding
variables
,7) A research project that follows the participants forward in time to identify future
outcomes is referred to as - ANSWER cohort study
8) In a study looking at the correlation between annual income and cholesterol level, one
concern was that the age of the participants might be a confounder because both
income and cholesterol generally increase with age. Which of the following
correlation methods could the researchers use to remove the influence of age on the
correlation between income and cholesterol level? - ANSWER partial correlation
9) Statistics use distinct symbols to represent specific information. Parameters are
usually represented by - ANSWER lowercase Greek letters
10) Researchers conducting a study with ____ power have a _____ probability of
committing a type ____ error. - ANSWER low;high;II
11) The ______ of any statistical test represents the probability that the results were
obtained by chance alone. - ANSWER p-value
12) A multivariate regression model looking at the association of intraocular pressure
(mm hg) with (1) having seasonal allergies, (2) wearing contact lenses, and (3) using
eye drops found a coefficient of determination (r2) of 0.23. How would you interpret
this statistic? - ANSWER seasonal allergies, contact lens use, and eye drop use
taken together explain 23% of the variation in intraocular eye pressure.
13) The local health department is interested in determining if there is a difference in the
incidence of childhood caries among children living in rural areas drinking untreated
well water and children living in cities drinking fluorinated water. A null hypothesis
could read - ANSWER the oral health of the rural children will not differ from that
of the city children.
14) A potential mistake when interpreting the data is to reject the H0 when it is true. This
is referred to as - ANSWER a type I error
15) Compute the mean for men, women, and overall for weight loss using the following
information: - ANSWER Women: 4.5 lbs; Men: 7.25 lbs; Total 5.6 lbs
,16) Researchers articulate the expected relationships between the variables by the
_______. - ANSWER null hypothesis
17) The study plan hypotheses - ANSWER must be very specific
18) The _____ of a test is the probability that the test result and the diagnosis agree -
ANSWER efficiency.
19) In a study looking at the association of mean hours worked per day (hours) and age
(years) with body mass index (BMI), the researchers used multivariate liner
regression. The regression equation is below. What BMI would you predict from this
equation for someone age 25 years who works 45 hours per week? - ANSWER
28.1
20) Statisticians use various scales to collect and/or identify data. The following is an
example of what type of scale? - ANSWER Ordinal scale
21) One response to the nursing shortage has resulted in the recruitment of nurses with
various educational levels. The results of one research study found that the level of
nursing education is critical in caring for certain patients. Therefore, we can conclude
that - ANSWER increasing the number of nurses without concern for educational
level has serious implications for critically ill patients
22) The researcher has determined the project has an α = 0.05. This indicates all values
outside ____ will be rejected. - ANSWER 95%
23) Under which of the following conditions would you need to use the Spearman
correlation coefficient and not the Pearson correlation coefficient? - ANSWER
One variable on the ordinal measurement scale and one is on the interval
measurement scale.
Neither variable is normally distributed.
There are only three outliers.
The two variables do not have a linear relationship.
, 24) Confidence intervals can be computed around the population mean from a single
simple mean using the - ANSWER central limit theorem
25) The alpha-level is defined by the researcher before any statistical tests are conducted.
This specific level is defined as - ANSWER statistically significant
26) Researchers rely on ________ to assist them in drawing meaningful conclusions on
data collected on a population through their research project. - ANSWER the
probability theory
27) The probability that the laboratory test is positive when given to a group of patients
who have the disease is referred to as - ANSWER sensitivity.
28) A study looking at the correlation between cholesterol level and distance between
home and work found a correlation coefficient of -0.13. How much of the variance in
cholesterol level is explained by distance between home and work (ie, what is the
coefficient of determination)? - ANSWER 1.7%
29) The first step to deciding which statistical technique to use is - ANSWER to
identify the question to be answered
30) Parts to Describing a Distribution - ANSWER Shape, outliers, center, variability
(SOCV)
31) Outlier Rule - ANSWER Any value more than 1.5IQR above Q3 or below Q1
32) Mean - ANSWER Average value of a distribution
33) Median - ANSWER Middle value of a distribution
34) Standard Deviation - ANSWER Typical distance of values from the mean
