BNAD 276 exam 2
albert wants to know the probability of a particular horse winning the race. Albert measured the weights of the jockeys and found the following distribution. what is the raw score for the jockeys in the 16th percentile?
95
which of the following is true when using the empirical rule for a set of sample data? approximately........of all observations are within 2 standard deviations of the mean.
95%
what type of relationship is indicated in the scatterplot?
a strong positive relationship
albert wants to know whether weight makes a difference. he measured 5 jockeys and found this: 90,95,100, and 110
a. the mean 100 b. the median is 100 d. both A and B are true
according to the central limit theorem, which is false?
as "n" increases, curve variability gets bigger
The central limit theorem states that, for any distribution, as "n" gets larger, the variability of the sampling distribution of the sample mean......
becomes smaller
the central limit theorem states that, for any distribution, as "n" gets larger, the variability of the sampling distribution of the sample mean...
becomes smaller
albert compared the time required to finish the race for 20 female jockeys and 20 male jockeys riding race horses. he wanted to know who averaged faster rides. this is a...
between participant design
marietta is a manager of a movie theater. she wanted to know whether there is a difference in concession sales for afternoon (matinee) movies vs. evening movies. she took a random sample of 25 purchases from the matinee movie (mean $7.50) and 25 purchases from the evening show (mean of $10.50). she compared these two means. this is an example of a........
between participant design
judy is running an experiment in which she wants to see whether a reward program will improve the number of sales in her retail shops. in her experiment she rewarded the employees in her Los Angeles stores with bonuses and fun prizes whenever they sold more than 5 items to any one customer. however, the employees in Houston were treated like they always have been treated and were not given any rewards for those 2 months. Judy then compared the number of items sold by each employee in the Los Angeles (rewarded) versus Houston (not rewarded) stores. In this study, a...........design was used.
between- participant, quasi experimental
albert wants to know the probability of a particular horse winning the race. albert measured the weights of the jockey's and found that bob had a z score of 1.5 while bill had a z score of -2.5. who is closer to the mean?
bob
albert wants to know the probability of a particular horse winning the race. albert measured the weights of the jockeys and found that bob had a z score of 1.5 while bill had a z score of -2.5. who is larger?
bob
albert wants to know the probability of a particular horse winning the race. albert measured the weights of the jockeys and found that bob had a z score of 1.5 while bill had a z score of -2.5. which is true?
bob is in the middle 95% of the curve
marcella wanted to know about the education background of the employees of the university of arizona. she was able to get a list of all the employees, and then she asked every employee how far they got in school. which of the following best describes this situation?
census
albert compared the time required to finish the race for 20 female jockeys and 20 male jockeys riding race horses. he wanted to know who averaged faster rides. the dependent variable is a(n)...
continuous
a survey was conducted to see whether men or women superintendents make more money. the dependent variable is...
continuous and quntitative
albert compared the time required to finish the race for 20 female jockeys and 20 male jockeys riding race horses. he wanted to know who averaged faster rides. this is called...
cross sectional design
Mr. Chu who runs a national company, wants to know how his informaiton technology (IT) employees from the west coast compare to his IT employees on the East Coast. He asks each office to report the average number of sick days each employee used in the previous 6 month, and then compared the number of sick days reported for the west coast and east coast employees. his methodology would best be described as:
cross-sectional comparison
mark and melvin work inside Intel's semiconductor fabrication plants. in these "clean rooms" the workers wear "bunny suits". mark and melvin are each assigned a different team to measure the workers. both teams measure the same sample of 100 workers and determine the very specific dimensions of their "bunny suits". mark spends a week training his team of data collectors, providing identical tape measures and creating a strict protocol for measuring the workers, with little instruction, and consequently melvin's workers make many more mistakes in recording the data, and the data are more variable. how would you explain the difference in variability between the two groups? the difference in variability between these two groups is due to:
differences in the amount of random error in the two samples, because as random error increases so will variability
A survey was conducted to see whether women superintendents make more money than men. it was predicted that women superintendents make more money but it turns out that this prediction was wrong. what should we conclude?
do not reject the null
albert compared the race times of 20 male and female jockeys for race horses. he tested whether the male riders averaged faster rides. he predicted that the male riders would be faster, but turns out that the female riders were faster; one tailed test and the prediction was wrong. which of the following is true?
do not reject the null
winnie found an observed t of 0.04, what should she conclude? (hint: notice that 0.04 is less than 1)
do not reject the null hypothesis
winnie found an observed z of 0.74, what should she conclude? (hint: notice that 0.74 is less than 1)
do not reject the null hypothesis
albert wants to know the probability of a particular horse winning the race. so he counted the number of times each horse won. based on this he is 80% sure that his horse will win. what approach to probability is he using?
empirical
albert wants to know whether weight makes a difference. he plotted the weight of each jockey using a pareto chart. how did he arrange the data?
in descending frequency from left to right with most frequency occurring category first
A survey was conducted to see whether women superintendents make more money than men. this is a...
one-tailed test
which of the following represents a significant finding?
p<0.05
what is the most typical form of a calculated confidence interval?
point estimate +/- margin of error
albert wants to know whether weight makes a difference. he plotted their weight in a frequency curve and found this:
positively skewed
marietta is a manager of a movie theater. she wanted to know whether there is a difference in concession sales for afternoon (matinee) movies vs. evening movies. she took a random sample of 25 purchases from the matinee movie (mean of $7.50) and 25 purchases from the evening show (mean $10.50). she compared these two means. this is an example of a.........
quasi experimental design
a survey was conducted to see whether men or women superintendents make more money. this is a...
quasi, between subject design
Victoria was also interested in the effect of vacation time of productivity of the workers in her department. in her department some workers took vacations and some did not. she measured the productivity of those workers who did not take vacations and the productivity of those workers who did (after they returned from their vacations). this is an example of a........
quasi-experiment
victoria was interested in the effect of vacation time on productivity of the workers in her department. she randomly sampled 100 workers and simply measured the productivity of those workers who did not take vacations and the productivity of those workers who did (after they returned from their vacations). this is an example of a...
quasi-experiment
a survey was conducted to see whether men or women superintendents make more money. the dependent variable is...
ratio level of measurement
albert compared the time required to finish the race for 20 female jockeys and 20 male jockeys riding race horses. he wanted to know who averaged faster rides. the dependent variable is a...
ratio level of measurement
compared to the standard deviation of the population, the standard error of the mean (especially for large samples) will be:
smaller
naomi is interested in surveying mothers of newborn infants, so she uses the following sampling technique. She found a new mom and asked her to identity other mothers of infancts as potential research participants, and continues this process until she found a suitable sample. what is this sampling technique called?
snowball sampling
albert wants to know whether the weight makes a difference. he created a scatterplot looking at weight and winning percentage and found that smaller jockeys won more often. describe this relationship.
strong negative
albert wants to know the probability of a particular horse winning the race. so he studies the health and breeding of the horse and the characteristics of the jockey. Based on this he is 80% sure that his horse will win. what approach to probability is he using?
subjective
albert compared the race times of 20 male and female jockeys for race horses. he wanted to know who averaged faster rides. which of the following is true?
the IV is gender while the DV is time to finish a race
what if we were looking to see if our new management program provides different results in employee happiness than the old program. what is the dependent variable?
the employees' happiness
albert wants to know whether weight makes a difference. he plotted their weight in a frequency curve and found this:
the mean was bigger than the mode
albert compared the race times of 20 male and female jockeys for race horses. he wanted to know who averaged faster rides. which of the following is true?
the null hypothesis is that there is no difference in race times between genders
what if we were looking to see if our new management program provides different results in employee happiness than the old program. what is the independent variable?
the type of management programs (new vs. old)
agnes compared the heights of the women's gymnastics team and the women's basketball team. if she doubled the number of players mesured (but ended up with the same means) what effect would that have on the results?
the variance would get smaller and the confidence interval would get narrower
a survey was conducted to see whether men or women superintendents make more money. if the null hypothesis was rejected we will conclude that...
there is a difference between the amount of money made
albert compared the race times of 20 male and female jockeys for race horses. he wanted to know who averaged faster rides. he concluded p<0.05 what does this mean
there is a significant different between the means
albert compared the race times of 20 male and female jockeys for race horses. he predicted that the female riders average faster rides. which of the following is true?
this is a one-tailed test
albert compared the race times of 20 male and female jockeys for race horses. he predicted that the male riders averaged faster rides. which of the following is true?
this is a one-tailed test
albert compared the race times of 20 male and female jockeys for race horses. he wanted to know who averaged faster rides. which of the following is true?
this is a quasi, between participant design
albert compared the race times of 20 male and female jockeys for race horses. he wanted to know who averaged faster rides. which of the following is true?
this is a two-tailed test
albert wanted to know if female jockeys have gotten better over the last 60 years, so he plotted the winning percentages for each year and looked for a trend over time. this is called...
time series design
which of the following variabilities is ration?
time until the next election
ian was interested in the effect of incentives for girl scouts on the number of cookies sold. he randomly assigned girl scouts into one of three groups. The three groups. The three groups were given one of three incentives and he looked to see who sold more cookies. the 3 incentives were; 1. trip to hawaii, 2. new bike or 3. nothing. this is an example of a.............
true experiment
a survey was conducted to see whether men or women superintendents make more money. this is a...
two-tailed test
match each level of significance to each situation. which situation would be associated with a critical z of 1.96?
two-tailed, alpha=0.05, significance level=0.05
judy is running an experiment in which she wants to see whether a reward program will improve the number of sales in her retail shops. (as described in previous question). she wants to use her finding with these two-samples to make generalizations about the population, specifically whether rewarding employees will affect sales to all of her stores. she rewarding employees will affect sales to all of her stores. she wants to generalize from her samples to a population, this is called......
using statistics to estimate a parameter
if we construct a 95% confidence interval rather than a 90% confidence interval (everything else remaining the same), the width of the interval would be....
wider
which of the following would represent a one-tailed test?
with an alpha of 0.05 test whether advertising increases sales
what is the z score for a 95% confidence interval of the population mean?
1.96
albert found that the standard deviation for the weight of the jockeys is 10 pounds, what is the variance?
100 pounds (variance is standard deviation squared)
albert wants to know the probability of a particular horse winning the race. albert measured the weights of the jockeys and found the following distribution. what percent of the jockeys will fall between 95 and 105 pounds (within one standard deviation of the mean)?
68%
albert wants to know the probability of a particular horse winning the race. albert measured the weights of the jockeys and found the following distribution. what is the percentile for those jockeys who are 105 pounds?
84%ile
albert wants to actually calculate the standard deviation for the weight of the jockeys. so he found the deviation scores and added them up. what did he get?
0
assume a distribution has a mean u=12 and standard deviation o=3. what is the probability of getting a score between 10 and 14?
0.4972
Judy is running an experiment in which she wants to see whether a reward program will improve the number of sales in her retail shops. (as described in previous question). she wants to use her findings with these two samples to make generalizations about the population, specifically whether rewarding empoyees will affect sales to all of her stores. she wants to generalize from her samples to population, this is called....
inferential statistics
Ian found a Sharpe Ratio of 2.5 for Investment A and 1.2 for investment A and 1.2 for investment B. which is preferred?
investment A
the central limit theorem states that, for any distribution, as "n" gets larger, the shape of the sampling distribution of the sample mean...
is closer to a normal distribution
the central limit theorem states that, for any distribution, as n gets larger, the shape of the sampling distribution of the sample mean........
is closer to a normal distribution
which of the following is a measurement of a construct (and not just the construct itself)
laughing
which of the following is the most influenced by outliers?
mean
the median is defined as the.............
middle point in a data set
the mode is defined as the............
most frequent value in data set
a survey was conducted to see whether men or women superintendents make more money. the null hypothesis is...
no difference between amount of money made
A survey was conducted to see whether men or women superintendents make more money. the independent variable is...
nominal level of measurement
steve who teaches in the economic department wants to use a simple random sample of students to measure average income. which technique would work best to create a simple random sample?
numbering all the students at the university and then using a random number table pick cases from the sampling frame.