ADMN 420 Final
The process of recording information from the entire population is known as _________
A census
What is the difference between bar charts and histograms?
Bar charts have columns that represent a group defined by a categorical variable, while a Histogram's columns represent a group defined by a quantitative variable
The normal probability distribution can be used to approximate the _________ distribution when np≥5 and nq≥5
Binomial
When calculating a confidence interval for proportions, we assume that promotion data follow the ___________
Binomial distribution
Calculating the average time callers wait on the phone for technical support is an example of ___________ statistics
Descriptions
The ___________ frequencies refer to the frequencies that are most likely to occur if the null hypothesis is true when performing a hypothesis test comparing two or more population proportions
Expected
According to the empirical rule, we would expect approximately 68, 95, and 99.7 percent of the values to fall within one, two and three standard deviations above and below the mean respectively for all distributions?
False
An event represents all of the possible outcomes of an experiment?
False
Call center managers prefer a large range for their standard deviation in call times as larger ranges shows consistency in their processes verses a smaller range?
False
Percentiles measure the approximate percentage of values in the data set that your value of interest is currently at?
False
The confidence interval for the mean is symmetrical around the population mean?
False
The hypothesis statement H0: μ=90 is an example of a one-tail hypothesis test?
False
The left and right ends of the normal probability distribution eventually touch the horizontal axis after a significant value of X is used?
False
The margin of error can be reduced by reducing the size of the sample?
False
The stem and leaf display is a graphical technique that can be used to display qualitative data.
False
The sum of cumulative relative frequencies for the cumulative relative frequency distribution should be equal to or very close to 1.0 due to rounding?
False
The z-score follows a normal distribution with μ=1 and σ=0, which is known as the standard normal distribution
False
When performing a hypothesis test comparing two population means, we need to assign Population 1 to the larger sample mean and population 2 to the smaller sample mean?
False
When the chi-square test statistic is greater than the chi-square critical value when comparing two or more population proportions, we fail to reject the hypothesis?
False
When the variance of a dataset is qual to 0, then the range of all those values in the data set will be equal to 1?
False
When we reject the null hypothesis for a chi-square test of independence, we are concluding that there is no relationship between the two variables?
False
When we use the t-distribution to calculate a confidence interval, we do not need to assume that the population of interest follows the normal probability distribution?
False
Your mobile number is an example of quantitative data.
False
A _____________ is a table that shows the number of data observations that fall into specific intervals
Frequency distribution
Type 2 errors are known as the consumer's risk, because the customer is potentially:
Getting a product from a process that is not performing properly
A car dealership performs a credit check on a potential customer. According to TransUnion, the customer's credit score is 660. This is an example of ________ data
Interval
Gathering information from potential customers in an effort to determine their preferences is an example of using statistics in the field of ___________
Marketing research
The ___________ is used to determine the probability of the intersection (joint probability) of the two events occuring, of P(A and B)?
Multiplication rule
What formula should be used when the order of object outputs is important?
Permutations
A ________ is a single call that best describes the population of interest
Point estimate
What is an example of a parameter?
Population mean
For a one way ANOVA test, if we calculate a test statistic that is greater than a critical statistic, then we can:
Reject the null hypothesis, as there is sufficient evidence to do so
What term measures the strength of the linear relationship between two variables?
Sample correlation coefficient
Because hypothesis testing relies on a sample, we expose ourselves to the risk that our conclusions about the population will be wrong because of ______________
Sampling error
When the population standard deviations are not known to us when comparing two population means, we substitute the sample standard deviations in their place. When we make this substitution, we rely on the _________ to conduct the hypothesis test
Students t-distribution
A single dice is rolled, many many times and the side that faces up is recorded. Eventually, we expect the number of times that we observe a 1,2,3,4,5 and 6 to be relatively close to one another. This expectation is due to ______________
The law of large numbers
A conditional probability is also known as a posterior probability, which is a revision of the prior probability using additional information.
True
A weighted mean allows you to assign more weight to the certain mean values and less weight to other mean values.
True
Analysis of variance (ANOVA) is a technique used to conduct a hypothesis test to compare three or more population means simultaneously?
True
For a chi-square test of independence, the expected frequencies are calculated under the assumption that the null hypothesis is ____________
True
For a one-tail hypothesis test, if the z- or t-test statistic is closer to zero than the critical value, we do not reject the null hypothesis?
True
Histograms that display discrete data commonly have gaps between their bars.
True
Sampling without replacement means that once a member of a population is chosen for a sample, it cannot be chosen again for the same sample?
True
Statistics is the mathematical science that deals with the collection, analysis, and presentation of data. Data that can be used as a basis for inference & induction.
True
The NULL hypothesis denoted by H0, represents the status quo and involves stating the belief that the population parameter is ≥, =, or ≤ a specific value?
True
The degrees of freedom for the sum of squares between for one-way ANOVA equal the number of populations being compared to minus one?
True
The mean and standard deviation for discrete probability distributions are useful when comparing two different distributions?
True
The mean of a discrete probability distribution is the weighted average of the outcomes of the random variables that comprise it?
True
The pooled variance is the weighted average of two sample variances drawn from two populations?
True
The probability that event A or B will occur refers to the union of event A and Event B?
True
The standard error of the mean is the sample mean standard deviation, which measures the variation around the mean of the sample means?
True
The total sum of squares (SST) measures the amount of variation between each data value and the grand mean?
True
The z-score in a normal probability distribution determines the number of standard deviations that a particular value (x) is from the median
True
Two events are considered mutually exclusive if they cannot occur at the same time during the experiment?
True
When two events are independent, the probability of them both occurring is simply the product of their individual probabilities of occurring?
True
Which of the following is not a condition of a discrete probability distribution? a. Each outcome in the distribution needs to be mutually exclusive with other outcomes in the distribution b. The probability of a success must exceed the probability of a failure c. The probability of each outcome, P(x), must be between 0 and 1 (inclusive) d. The sum of the probabilities for all the outcomes in the distribution needs to add up to 1
b. The probability of a success must exceed the probability of a failure
Which of the following experiments does not generate a continuous random variable? a. Measuring the number of ounces of a soda in a bottle b. Recording the number of minutes a customer waits on hold for tech support c. Counting the number of customers who enter a store during the business day d. Recording the number of miles traveled between two locations
c. Counting the number of customers who enter a store during the business day
Which of the below is a measure of central tendency? a. probability b. standard deviation c. correlation coefficient d. median e. both b and d f. none of the above
d. Median
A golfer claims that his average golf score at the courses he plays regularly is less than 90. A type 1 error would occur if the golfer concludes that the average score is ____________
less than 90 when, in reality, the average score is 90 or more
The central limit theorem (CLT) states that the sample means ___________
of large-sized samples will be normally distributed regardless of the shape of their population distributions
