Kine 303
In a normally distributed data set with a mean of 100 and SD of 15, what is the Z score of someone who scores 115?
+1
Which of the following r values reflects the strongest relationship between X and Y?
- .90
In a normally distributed data set with a mean of 100 and SD of 15, what is the Z score of someone who scores 70?
-2
In a normally distributed data set with a mean of 100 and SD of 15, what is the Z score of someone who scores 55?
-3
If your initial α was set at .05, and your post hoc comparisons required 10 total comparisons, a Bonferroni correction would yield a per comparison α of
.005
Which α level is associated with the smallest critical F value?
.05
If there is absolutely no relationship between two variables, the Pearson r would be
0
The multiple correlation coefficient ranges from
0 to 1.0
What is the probability of rolling a 5 with a 6-sided die?
1/6
Calculate the variance inflation factor for two independent variables that have an R2 of .9. VIF = 1/(1- R2).
10
It was determined that the variance for a distribution of eight bench press test scores was 100. What is the standard deviation of the data set?
10
Ten sprinters ran a 100-meter dash. The average time the sprinters took to complete the 100-meter dash was 11.7 seconds and the standard deviation was 1.2 seconds. What is the coefficient of variation?
10
A data set includes 99 scores of 10 and 1 score of 20. The individual who scored20 will receive what percentile rank?
100
In a grouped frequency distribution it is common to group scores into ______ groups.
15
In a normally distributed data set with a mean of 50 and SD of 5, what percentage of scores are 45?
15
If there is a high negative relationship (e.g., r = -.95) between weekly exercise duration and body fat percentage, you would expect someone with a weekly exercise Zscore of -2 to have a body fat percentage Zscore of about
2
If you are trying to use X to predict Y and you have data from 22 subjects, what is the degree of freedom (df) value to be used in the determination of statistical significance?
20
We are using X to predict Y, and the bivariate regression results in the following equation: YP=10 + 5X. If someone has a X score of 2, what is their predicted Y score?
20
Twenty-five students completed a vertical jump test yielding a single distribution of scores. Dr. X wants to calculate the variance of the distribution. How many degrees of freedom should be used for the calculation if Dr. X considers the distribution to be a sample of scores?
24
Calculate the degrees of freedom for a multiple regression where data from 33 students were collected in order to predict scores. The independent variables were age, weight, height, 100-meter dash time, and 1-mile run time. df = n ? k ? 1.
27
If there are five levels in my repeated measures ANOVA, and I have 10 subjects, what is my dferror?
36
For variables X and Y, you calculate Pearson r to be .6. How much variance in Y is accounted for by X?
36%
Mr. E's physical education class ran as many laps as they could without stopping around a 400-meter track. The following is the distribution of laps completed by the students. 1, 2, 4, 4, 4, 5, 6, 6, 7, 10, 12.What is the mode of the distribution?
4
In a normally distributed data set with a mean raw score of 50 and SD of 5, what raw score is associated with a Z score of -2?
40
The quartile range divides the percentile scale into _____ equal parts that have a range of _____ percentage points.
4; 25
With an α level of .05, we must accept the null if the p value indicates our risk of committing a type I error is greater than
5%
Mr. E's physical education class ran as many laps as they could without stopping around a 400-meter track. The following is the distribution of laps completed by the students. 1, 2, 4, 4, 4, 5, 6, 6, 7, 10, 12.What is the mean of the distribution?
5.5
If the distribution of scores is relatively normal, when scores are standardized the most common scores will be around the ______ percentile.
50th
Which of the following statements is true for within-subjects (repeated measures) ANOVA?
Comparisons are made between different measurements from the same subjects.
Distribution 1 has a sum of squared deviations of 1,000 and a sample size of 10. Distribution 2 has a sum of squared deviations of 1,500 and a sample size of 50. Which distribution has a greater standard deviation?
Distribution 1 has a greater standard deviation.
Distribution 1 has a sum of squared deviations of 1,000 and a sample size of 10. Distribution 2 has a sum of squared deviations of 1,500 and a sample size of 50. Which distribution has more variance?
Distribution 1 has more variance.
Your bivariate regression resulted in a line of best fit with a slope of 0.5. What does that mean?
For every one-unit increase in the independent variable, you would expect the dependent variable to increase by 0.5 units.
If you are trying to see if 40-yard sprint time predicts jump height, what would be your independent and dependent variables?
IV= sprint time, DV= jump height
All else being equal, what will happen to the denominator of the F ratio if the within-group variances are increased?
It will increase.
All else being equal, what will happen to the numerator of the F ratio if the between-group variances are increased?
It will increase.
Person A scored in the 50th percentile. Person B scored in the 80th percentile. If persons A and B both increase their score by the same absolute amount (e.g., 10 units), who will have the greatest change in percentile rank?
Person A will have the greatest change in percentile rank.
Why are normal distributions so common with data?
Randomness leads to normal distributions according to the central limit theorem.
Dr. P had her entire class complete a push-up test and a sit-up test. Student J performed 21 push-ups and 27 sit-ups. When Dr. P standardized the scores from her students, Student J's raw scores placed him at the 60th percentile for the push-up test and the 40th percentile for the sit-up test. How did Student J compare to the other students in the class?
Student J was better at the push-up test than the sit-up test.
Dr. T had his entire class complete a push-up test and a sit-up test. Student R performed 21 push-ups and 27 sit-ups. When Dr. T standardized the scores from his students, Student R's raw scores placed her at the 50th percentile for both the push-up test and the sit-up test. How did Student R compare to the other students in the class?
Student R was equally good at both tests.
Student X performed 6 pull-ups, which scored in the 45th percentile of the population, and Student Y performed 20 pull-ups, which scored in the 90th percentile of the population. If Student X and Student Y were tested again and both increase their raw scores by 3, who will likely have a greater increase in standard score?
Student X will have a greater increase in standard score
Student X scored in the 50th percentile and Student Y scored in the 75th percentile of the population for scores. Based on this information alone, which of the following is determined?
Student Y has a greater than Student X.
When a multiple regression is performed on standardized Z scores the slope coefficients are called
β weights
If the raw deviation scores from the mean are added together for a given distribution of numbers and the result is not equal to zero which of the following is true?
The calculated mean is not correct.
A study is investigating the effects of low-carbohydrate and low-fat diets on change in blood triglyceride levels. Which of the following statements is FALSE?
The independent variable is change in blood triglycerides.
What is the relationship of the mean, median, and mode in a positively skewed distribution of numbers?
The mean will be greater than the median, and the median will be greater than the mode.
What is the relationship of the mean, median, and mode in a negatively skewed distribution of numbers?
The mode will be greater than the median, and the median will be greater than the mean.
During post hoc analysis of a repeated measures ANOVA, a pairwise comparison yielded a Bonferroni-corrected confidence interval (CI) of -5.2 to +1.8. Which of the following is an appropriate interpretation?
The pairwise comparison is not statistically significant.
What is the relationship of the mean, median, and mode in a normal distribution of numbers?
The three measures will fall at or very near the same number.
The t test used in a repeated measures situation (e.g., same subjects tested twice) does not have sphericity assumption, while the repeated measures ANOVA (3+ means to compare) does assume sphericity. Why is there no sphericity assumption in the t test situation?
There are only two means in the t test situation, so there is only one set of difference scores.
For repeated measures ANOVA, if your data did violate the assumption of sphericity, what is true?
There is a greater likelihood of committing type I error (if no correction is used).
If you want to compare the effect of low-fat versus low-carbohydrate diets on change in blood triglyceride levels, which would be an acceptable null hypothesis?
There is no difference in change in blood triglyceride levels between low-fat and low-carb diets.
What is the purpose of using standardized Z scores for a multiple regression rather than raw scores?
They standardize the scale of the slope coefficients.
All else being equal, which of the following will cause a decrease in the standard error of the mean?
a decrease in the standard deviation
What type of measure should be used to describe how scores tend to cluster in a distribution of scores?
a measure of central tendency
The statistical hypothesis tests from Dr. X's study on the effects of a preworkout supplement on bench press repetitions to failure show a significant difference between the condition performed with the preworkout supplement and the placebo condition. However, in reality there is no effect of the preworkout supplement on bench press performance. The result of the study is apparently
a type I error
The statistical hypothesis tests from Dr. Y's study on the effects of a preworkout supplement on bench press repetitions to failure show no significant difference between the condition performed with the preworkout supplement and the placebo condition. However, in reality there is a positive effect of the preworkout supplement on bench press performance. The result of the study is apparently
a type II error
Which of the following relationships would you expect to have a negative Pearson r?
age (X) and strength (Y) in older adults
Which of the following methods of multiple regression forces all independent variables into the model and then begins to remove variables that do not cause a significant decrease in the R2 value?`
backward elimination
In ANOVA, the F ratio is the ratio of _________ variance to _________ variance.
between-group; within-group
All else being equal, increasing the sample size will __________ critical t.
decrease
Statistics are ______________.
characteristics of samples
Systolic blood pressure is an example of a _____ variable.
continuous
The 6-minute walk test quantifies how far an individual can walk over a 6-minute time period. This results in a score that is measured in meters (and fractions thereof). The data are
continuous
When dealing with large data sets, it makes most sense to
create a frequency distribution of the data
At any df level, decreasing α will __________ the likelihood that statistical significance is reached.
decrease
The Huynh-Feldt (HF) and Greenhouse-Geisser (GG) correction methods serve to
decrease the degrees of freedom used to determine statistical significance
If you are comparing the volleyball team's preseason vs. postseason vertical jump heights, what type of ttest should you use?
dependent t test
The ttest that is most similar to a repeated measures ANOVA is
dependent ttest
The coefficient of variation can be found by ________ and multiplying by 100.
dividing the standard deviation by the mean
The assumption of sphericity is met when there is
equal variance of difference scores between measurement periods
Dr. Stats has developed a statistical model to predict whether athletes will, or will not, experience a stress fracture based upon their blood concentrations of vitamin D. The subjects in the study are Division 1 collegiate volleyball players. Dr. Y wonders whether the model will predict stress fractures in high school volleyball players. Dr. Y's question centers on the question of
external validity
If your calculated t is greater than your critical t, your p value (calculated by computer software) will be greater than your α value.
false
In a cumulative frequency figure, as X-axis values increase, the Y-axis values get smaller.
false
In an observational study, if X is correlated with Y, then X has been definitively shown to cause Y.
false
In order to find variance, add up the raw deviation scores from the mean and divide by the number of scores.
false
Which of the following is an example of experimental research?
having two groups eat different diets and measuring their change in blood pressure
A person who scores in the 80th percentile in the population for body weight is
heavier than average in the population
Which of the following methods of multiple regression allows the investigator to choose the order that X variables are added to the model?
hierarchical
Between-group variability is a measure of
how the group means vary about the grand mean
Within-group variability is a measure of
how the individual scores vary about the group means
All else being equal, decreasing a sample size should ___________ sampling error.
increase
All else being equal, decreasing the within-group variance will _______ your F ratio.
increase
All else being equal, increasing the mean difference between groups will ______ the likelihood of finding a significant p value from a ttest.
increase
All else being equal, increasing the number of subjects in a repeated measures ANOVA will _______ the F ratio.
increase
All else being equal, decreasing the sample size will
increase critical t
If someone's score on an independent variable is zero, what will be that person's predicted score on Y (YP)?
the Y-intercept
All else being equal, increasing the sample size will
make a confidence interval narrower
Unlike the between-subjects ANOVA, repeated measures ANOVA can account for between-subjects variability. If you think of inferential statistical calculations as determining sources of signal and noise, the information associated with the between-subjects variability is considered
noise
Choice of college major is an example of a _____ variable
nominal
If a distribution of data has tails that are equal on both sides, the distribution would
not be skewed
Which of the following is used to examine the correlation between a single X variable and the Y variable with the influence of the other X variables removed?
partial correlation
A distribution that is shorter and has thinner tails than a normal distribution is a __________ distribution.
platykurtic
If a distribution of data has a longer tail extending toward the right, or the higher values, the distribution would be
positively skewed
Which of the following is the correct symbol to represent the partial correlation of X2 and Y with X1 removed?
rYX2.X1
In a distribution of scores, the highest score was 35 and the lowest was 20; the difference between these scores is 15. Which measure of variability does this describe?
range
A measure of blood high density lipoprotein (HDL) is an example of what type of data?
ratio
A thermometer is considered ______________ if it can display the same value under the same thermal conditions.
reliable
Multiple regression is useful when an investigator wants to
see if a prediction can be improved by using information from more than one X variable
Multicollinearity causes increased confidence intervals about the
slope coefficients
Dr. Stats has developed a statistical model to predict whether athletes will, or will not, experience a stress fracture based upon their blood concentrations of vitamin D. The dependent variable is
stress fractures
Which of the following defines the range of a data set?
the distance from the highest to the lowest value in a data set
Which of the following would you estimate to have a bimodal distribution?
the distribution for height that includes both males and females
Alpha (α) is equal to ____________.
the probability of rejecting the null when the null is true
The mode is
the score that occurs most frequently
The standard error of the mean is
the standard deviation of the sampling distribution of the mean
The mean is
the statistical term for the arithmetic average
If your calculated t is less than your critical t, your p value (calculated by computer software) will indicate
there was no significant difference between groups
The coefficient of variation allows us to normalize variability so we can compare variability from different variables.
true
When you use multiple ttests instead of ANOVA, you increase your likelihood of committing_______ error.
type I
You perform a statistical hypothesis test, and the calculations lead you to accept the null hypothesis. If in fact the null hypothesis is false, what type of error would you have committed?
type II error
Dr. Who wonders whether a vertical jump test is useful to assess leg power. This question centers on the issue of
validity
Dr. X wishes to test the strength of individuals with Parkinson's disease. Dr. X decides to use the 6-minute walk test as a measure of muscle strength. Dr. Contrarian thinks the 6-minute walk test is a poor choice since it primarily assesses the cardiorespiratory fitness of the individuals, not their strength. Dr. Contrarian's criticism concerns the _____ of the test.
validity
Body mass is a
variable
Dr. C is performing a forward selection model of multiple regression using a software package. The independent variables of height, weight, age, vertical jump height, college major, and GPA will be used to try to predict 1RM squat for students in exercise physiology class. When will independent variables cease to be added to the model?
when the addition of another independent variable does not cause a statistically significant increase in the R2 value of the model
the raw deviation scores from the mean are added together for a given distribution of numbers. What is the result?
zero
If you are completing an independent samples ttest, which of the following pairs of data are most likely to be statistically different?
{10,10,20,20,30,30} {30,30,40,40,50,50}
A normally distributed data set has a sample mean of 500 and SEM of 50. What is the approximate 95% CI associated with this dataset?
~400 to 600
In a normal distribution, about what percentage of scores lie outsideof the ±2 SD range?
~5%
In regression, r2 is used to describe the percent variance of a dependent variable that can be explained by the variance in an independent variable. What t test measure is most comparable to r2?
ω2
What are the odds of rolling a 5 with a 6-sided die?
1 to 5
Mr. E's physical education class ran as many laps as they could without stopping around a 400-meter track. The following is the distribution of laps completed by the students. 1, 2, 4, 4, 4, 5, 6, 6, 7, 10, 12.What is the median of the distribution?
5
A percentile scale that is divided into 10 parts, each having a range of 10 percentage points, is called the
decile range
All else being equal, decreasing the between-group variance will ________ your F ratio.
decrease
Measures of variability
describe the scatter, or spread of scores, in a distribution
It is impossible to calculate the median if there is an even number of scores in a distribution, because there is no middle number.
false
Standardizing scores does not allow comparisons between two sets of scores with different units.
false
There can be only a single mode in any given distribution.
false
The more negative the kurtosis score, the __________ the distribution.
flatter
In a frequency polygon graph the Y-axis represents
the frequency of the scores
In a histogram, the Y-axis represents
the frequency of the scores
Dr. C is performing a forward selection model of multiple regression using a software package. The independent variables of height, weight, age, vertical jump height, college major, and GPA will be used to try to predict 1RM squat for students in exercise physiology class. Which variable will be added to the model first?
the independent variable with the highest correlation with 1RM squat
The median is
the number associated with the 50th percentile
The degrees of freedom for any scenario is defined as
the number of values that are free to vary
You are comparing the effects of low-fat, low-carb, and low-protein diets on percent body fat and body mass. The independent variable contains how many levels?
three
A normal (Gaussian) distribution will have the same values for the mean, median, and mode.
true
All else being equal, dependent ttests are typically more powerful than independent ttests.
true
If a distribution of scores is very platykurtic in nature it will have more variance than a leptokurtic distribution of scores.
true
In ANOVA, the F ratio is a signal to noise ratio.
true
In a normal distribution, the percentage of area under the curve between the mean and any Z score is equal to the percentage of scores that lie between the mean and the specified Z score.
true
No matter how many times you roll a six-sided die, for each roll, the probability of the die landing on a six is 1/6.
true
SS error is the amount of variability that is not accounted for by S Stime and SS subjects.
true
Standardizing scores is a useful technique because it allows for the interpretation of raw scores in relation to the population.
true
The standard deviation can be found by taking the square root of the Select one:
variance
What is the probability of getting tails when flipping a fair coin?
0.5
Fifteen high school basketball players performed a vertical jump test. A score of 22 inches was the median. What percentile rank is a score of 22 inches?
50th percentile
If your one-way ANOVA is comparing four groups, how many possible ttest comparisons can you make?
6
The following multiple regression equation was used to predict performance on a handgrip endurance test. Endurance time = 5.37 (height) + 9.56 (weight), where SEb is 1.6, the critical t is 2.08, and CI = b± t(SEb). Calculate the confidence interval for the slope coefficient of weight.
6.2 to 12.9
In a normally distributed data set with a mean raw score of 50 and SD of 5, what raw score is associated with a Z score of +2?
60
Thirty professors at the University of Statistics ran a 1-mile race. The professor who placed seventh scored at the _______ percentile.
80th
In a normally distributed data set with a mean of 50 and SD of 5, approximately what percentage of scores are ≤ 55?
85
Which level of confidence (LOC) value is associated with the highest (largest) α value?
90%
Thirty professors at the University of Statistics performed a push-up test. Dr. Q performed 30 push-ups, which was more than 25 other professors, but 1 other professor also performed 30 push-ups. What was Dr. Q's standardized score?
90th percentile
Dr. R has children of three different age groups run a 20-meter dash as fast as they can. Dr. R wants to compare the times of the three groups of children to determine if there is a statistically significant difference between them. Dr. R doesn't know how to perform an ANOVA so multiple ttests are used to compare the data instead. What is the primary issue with the methods Dr. R has used?
Because multiple ttests were used, there is an increased risk of type I error.
Dr. R has children of three different age groups run a 20-meter dash as fast as they can. Dr. R wants to compare the times of the three groups of children to determine if there is a statistically significant difference between them. Dr. R doesn't know how to perform an ANOVA so multiple t tests are used to compare the data instead. What is the familywise error rate in relation to the original α level that was set?
It is greater than the original α level.
Dr. T compares vertical jump scores between 20 football players and 20 tennis players and finds a significant mean difference of 10 centimeters. The next day Dr. T compares the vertical jump scores of 20 basketball players and 20 soccer players. The mean difference between basketball players and soccer players is again 10 centimeters. If Dr. T uses a ttest to determine whether the mean difference is statistically significant, what will he find?
It is impossible to tell.
Your score ranked you in the 80th percentile of a normally distributed data set. If your score does not change, but additional scores are added that cause the distribution to more leptokurtic, how will your percentile rank change?
It will increase.
All else being equal, what will happen to the denominator of the F ratio if the between-group variances are increased?
It will stay the same.
All else being equal, what will happen to the numerator of the F ratio if the within-group variances are increased?
It will stay the same.
If you ranked in the 90th percentile and a 50th percentile score was replaced with a 55th percentile score, what would happen to your percentile rank?
It would not change.
You are investigating the relationship between X and Y. If the 95% CI for the Pearson r spans from .05 to .70, what is your conclusion?
The relationship is significant at α = .05
Which of the following relationships would you expect to have anegativePearson r?
age (X) and strength (Y) in older adults
Typically, the research hypothesis in a study is consistent with the
alternate hypothesis
A multiple correlation coefficient of -.93 indicates which of the following?
an error (a negative multiple correlation coefficient is not possible)
All else being equal, which of the following will cause a decrease in the standard error of the mean?
an increase in the sample size
Dr. Stats has developed a statistical model to predict whether athletes will, or will not, experience a stress fracture based upon their blood concentrations of vitamin D. The study is _____ study.
an observational
Dr. Who wants to understand the relationship between calcium intake and bone mineral density. Subjects keep dietary records for a month, from which average daily calcium intake is quantified. Bone mineral density is then quantified with a DEXA scanner. This is an example of _____ study.
an observational
If you are a subject in a study that is comparing three groups and your data were used in two of the three groups, what ANOVA assumption have you violated?
independence of scores
If you are comparing 1RM bench press abilities of the volleyball team vs. the basketball team, what type of ttest should you use?
independent ttest
Question text A disadvantage of the mode is that it
is a terminal statistic because it isn't useful for further calculations
A calculated Pearson r is NOT statistically significant when
it is less than the critical r value
Which measure of central tendency is always affected by every score in a data set?
mean
Which data will result in the largest t?
mean difference = 100; SE of the mean difference = 1
Which statistical hypothesis may be an acceptable null hypothesis?
mean of A = mean of B
A 90% CI is equal to
mean ± 1.65 SEM
A 95% CI is equal to
mean ± 1.96 SEM
A 99% CI is equal to __________.
mean ± 2.58 SEM
Which measure of central tendency is useful with highly skewed data sets because it is unaffected by extreme outliers?
median
You do a study to predict resting blood pressure (mmHg) from self-reported time (minutes) of exercise performed per week. What are the units for the Y-intercept (a) of the regression analysis?
mmHg
You do a study to predict resting blood pressure (mmHg) from self-reported time (minutes) of exercise performed per week. What are the units for the slope (b) of the regression analysis?
mmHg/minute
You do a study where you measure body fat percentage once per month for 12 months in a group of 10 subjects. Which sets of scores would you predict would be the most highly correlated with each other?
month 9 and month 10
The more positive the kurtosis score, the ___________ the distribution.
more peaked
When compared to between-subjects ANOVA, you would expect within-subjects (repeated measures) ANOVA to have
more statistical power
ANOVA is typically used when you are comparing ________ means.
more than two
A problem with multiple regression called ______ may occur when two independent variables are highly correlated with one another.
multicollinearity
If a distribution of data has a longer tail extending toward the left, or the lower values, the distribution would be
negatively skewed
Imagine a distribution in which lots of scores are bunched at high values and relatively few scores have low values. This distribution is
negatively skewed
Dr. U is performing statistical analyses to determine whether a difference exists between BMI among professors and students at his university. Dr. U finds the 95% CI about the mean difference between students and professors runs from -0.5 to 3.4 kg/m2. Would a ttest find a statistically significant difference between the groups?
no
If you are trying to determine if a population of people have high systolic blood pressure by comparing their systolic blood pressure values to the high systolic blood pressure cutoff set by the American Heart Association, what test will you perform?
one-sample t test
When is an ordered listing of data presented in a single column?
only when the data set is relatively small
In order to determine the interquartile range for a distribution of scores, take the difference of the _____ scores at the _____ and _____ percentile points.
raw; 25th; 75th
In null hypothesis significance testing, if your p value is less than your α value, you should
reject the null hypothesis
