Straighter line Statistics Final Exam
Questions and Correct Answers
Already Passed
A researcher is studying the relationship between academic and sports performance in
100 college athletes. She runs a regression model with the number of games started as
the independent variable and grade point average as the dependent variable this model
yields a slope of B = 0.3. A two tail test of this estimate produces a T statistics of -2.1
assuming a significance threshold of P < 0.05, how should the researcher interpret
these results? - Answer-Each additional gameplay is associated with a 0.3 decline in
GPA
Sociologist wants to examine academic performance across grade levels in an
elementary school. The number of students is not the same in each grade. Which
sampling method would be most appropriate? - Answer-Stratified random sampling
A researcher asked children to complete a math test. Half of the children are told they
will be rewarded for every correct answer; the other will receive the reward. The
researcher will compare the main test scores for the two groups. What type of research
design is this? - Answer-Census
Simple, random sampling is used in various study designs to allow for - Answer-A
sample that is representative of its population
To increase the generalizability of studies results, participants must be - Answer-
Representative of the population of interest
Which type of data would have a discrete probability distribution? - Answer-Number of
children per household in a census
A video game got a thumbs up rating from 400 out of 1000 customer surveyed. The
customers included 250 women. Assuming that gender does not have any influence on
the rating, what is the chance that any randomly selected participant will be a woman
who gave the game a thumbs up rating? - Answer-10%
A dining guide reviewed all of the restaurants in a town. Only six restaurants received a
four star rating. 17 receive three stars; 18 receive two stars; and nine received a one
, star rating. Based on this information, what is the probability of a restaurant receiving a
four star rating? - Answer-0.12
The table shows the likelihood that a team will score a certain number of touchdowns in
a football game. What is the probability that the team will score at least two
touchdowns? - Answer-0.64
The main score on a college entrance exam is 1200, and the standard deviation is 100.
If the scores are normally distributed, what is the likelihood of the score greater than
1450? - Answer-0.0062
What type of distribution is depicted in the graph? - Answer-Normal
A school gives an exam for which the scores are normally distributed. What proportion
of students score within 2.3 standard deviations of the mean? - Answer-0.98
The mean score for 18 holes of golf on the parkvale municipal course is 68, with a
standard deviation of 12. Low score is 95. What is Z - score does this correspond to? -
Answer-2.25
Damien determines that the difference is he found in his study are statistically significant
at the 0.05 level of significance. What is the correct interpretation of the finding? -
Answer-95% of the study participants achieve the level of performance expected
The central limit theorem says that if the sample size doubles, the sampling distribution
of the sample mean will - Answer-Approach a normal distribution
Scores on a certain standard achievement test are normally distributed with mean μ =
100 and standard deviation σ= 10. If you take multiple samples of size 16, what percent
of sample of means will be between 95 and 105. - Answer-95.4%
A student performed a chi square test with 5° of freedom. What would be the critical
value of the chi square statistic, assuming a significance level of P< 0.05 - Answer-
11.07
Withdrawn from a normal distribution, 95% of the sample means will fall within how
many standard deviations of the population - Answer-1.96
A maple syrup manufacturer asked 100 customers to rate its brand of maple syrup on a
scale of one to 10. The mean rating was seven, with a sample standard deviation of 1.5.
Based on this sample, what is the 95% confidence interval for the estimate of the
population mean? - Answer-(6.7, 7.3)
A regression analysis suggest that the number of children and employee has predicts
the number of personal days he/she will take off work. The life of the regression line is
Questions and Correct Answers
Already Passed
A researcher is studying the relationship between academic and sports performance in
100 college athletes. She runs a regression model with the number of games started as
the independent variable and grade point average as the dependent variable this model
yields a slope of B = 0.3. A two tail test of this estimate produces a T statistics of -2.1
assuming a significance threshold of P < 0.05, how should the researcher interpret
these results? - Answer-Each additional gameplay is associated with a 0.3 decline in
GPA
Sociologist wants to examine academic performance across grade levels in an
elementary school. The number of students is not the same in each grade. Which
sampling method would be most appropriate? - Answer-Stratified random sampling
A researcher asked children to complete a math test. Half of the children are told they
will be rewarded for every correct answer; the other will receive the reward. The
researcher will compare the main test scores for the two groups. What type of research
design is this? - Answer-Census
Simple, random sampling is used in various study designs to allow for - Answer-A
sample that is representative of its population
To increase the generalizability of studies results, participants must be - Answer-
Representative of the population of interest
Which type of data would have a discrete probability distribution? - Answer-Number of
children per household in a census
A video game got a thumbs up rating from 400 out of 1000 customer surveyed. The
customers included 250 women. Assuming that gender does not have any influence on
the rating, what is the chance that any randomly selected participant will be a woman
who gave the game a thumbs up rating? - Answer-10%
A dining guide reviewed all of the restaurants in a town. Only six restaurants received a
four star rating. 17 receive three stars; 18 receive two stars; and nine received a one
, star rating. Based on this information, what is the probability of a restaurant receiving a
four star rating? - Answer-0.12
The table shows the likelihood that a team will score a certain number of touchdowns in
a football game. What is the probability that the team will score at least two
touchdowns? - Answer-0.64
The main score on a college entrance exam is 1200, and the standard deviation is 100.
If the scores are normally distributed, what is the likelihood of the score greater than
1450? - Answer-0.0062
What type of distribution is depicted in the graph? - Answer-Normal
A school gives an exam for which the scores are normally distributed. What proportion
of students score within 2.3 standard deviations of the mean? - Answer-0.98
The mean score for 18 holes of golf on the parkvale municipal course is 68, with a
standard deviation of 12. Low score is 95. What is Z - score does this correspond to? -
Answer-2.25
Damien determines that the difference is he found in his study are statistically significant
at the 0.05 level of significance. What is the correct interpretation of the finding? -
Answer-95% of the study participants achieve the level of performance expected
The central limit theorem says that if the sample size doubles, the sampling distribution
of the sample mean will - Answer-Approach a normal distribution
Scores on a certain standard achievement test are normally distributed with mean μ =
100 and standard deviation σ= 10. If you take multiple samples of size 16, what percent
of sample of means will be between 95 and 105. - Answer-95.4%
A student performed a chi square test with 5° of freedom. What would be the critical
value of the chi square statistic, assuming a significance level of P< 0.05 - Answer-
11.07
Withdrawn from a normal distribution, 95% of the sample means will fall within how
many standard deviations of the population - Answer-1.96
A maple syrup manufacturer asked 100 customers to rate its brand of maple syrup on a
scale of one to 10. The mean rating was seven, with a sample standard deviation of 1.5.
Based on this sample, what is the 95% confidence interval for the estimate of the
population mean? - Answer-(6.7, 7.3)
A regression analysis suggest that the number of children and employee has predicts
the number of personal days he/she will take off work. The life of the regression line is
