Data Analytics Test 1

Identify the shape of the distribution in the figure below. Skewed left Symmetric Approximately bell shaped Skewed right

Skewed right

Which of the following is NOT true about quartiles? Quartiles divide data to four equal or roughly equal parts. The choices are all true. The difference between the third and first quartiles is referred to as the interquartile range (IQR). The second quartile (or the 50% percentile) is equal to the median.

The choices are all true.

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the relative frequency of the 21-24 bin? ​ ​ 0.05 0.14 0.25 2.5

(Count all the boxes and divide by 21-24 bin) 0.25

When is a geometric mean used?

In analyzing growth rates in financial data

How to calculate coefficient of variance

Standard deviation/mean

According to the _____________ approximately 68% of the data values will be within ____ standard deviation of the mean. law of big numbers, 1 law of big numbers, 0.1 empirical rule, 0.1 empirical rule, 1

empirical rule, 1

Any data value with a z-score less than ____ or greater than ____ is considered to be an outlier. Such data should be reviewed to ensure accuracy. -3, +3 -1, +1 -4, +4 -2, +2

-3, +3

The box in a box plot contains approximately ____ of the data. 75% 50% 25% It depends on whether or not there are outliers in data.

50%

What is geometric mean?

A measure of location that is calculated by finding the nth root of the product of n values

The major developments that have boosted recent explosive growth in the use of analytical methods in business applications are: A: Technologies and devices producing large amounts of data. B: The development of algorithms and methods for handling, processing, and visualizing large amounts of data C: The exponential growth in computing power and storage capability

A, B, and C

A manager of a fast food restaurant wants the drive-thru employee to ask every fifth customer if he or she is satisfied with the service. Who makes up the population? All customers who use the drive-thru window of this fast food restaurant All survey respondents All customers of this restaurant The proportion of customers who say they are satisfied with their service

All customers who use the drive-thru window of this fast food restaurant

Which of the following best exemplifies big data? Cellphone owners across the globe generate data by calling, texting, tweeting, and browsing the Web on a daily basis. Five hundred Facebook users upload one thousand pictures per day. A pharmacy keeps track of customer purchases to send their customers coupons. A local grocery store collects data from those that scan their loyalty card.

Cellphone owners across the globe generate data by calling, texting, tweeting, and browsing the Web on a daily basis.

__________ are collected from several entities at the same point in time. Time series data Categorical and quantitative data Cross-sectional data Random data

Cross-sectional data

____________ analytics encompasses reports, data dashboards, and summary statistics. Its focus is mainly on understanding past data or events. predictive descriptive prescriptive decision

Descriptive

______________________ is the most critical step of the decision-making process. Evaluating the alternatives Identifying and defining the right problem Choosing an alternative Determining the set of alternatives

Identifying and defining the right problem

Which of the following measures is mostly unaffected by outliers (extreme values)? Median Mean Range All the choices are considerably affected by outliers

Median

The unit of standard deviation is __________. The same as that of the data Is the square of that of that of the data the square root of that of the data The standard deviation is unit-free

The same as that of the data

Creating a scatter plot is an effective way for identifying possible non-linear relationship between two variables. True False

True

Data that are too large or too complex to be handled by standard data-processing techniques and typical desktop software are refereed to as big data.​ True False

True

There is no strict rule for determining the number of bins when creating a histogram for numerical data. Rather, a good number of bins is often identifiable by trial and error. True False

True

True or False? Correlation analysis can capture linear relationship. It cannot capture non-linear relationship if one exists. True False

True

True or false? Z-score helps to determine how far a particular value is from the mean relative to the data set's standard deviation. True False

True

Which of the following refers to the possible inconsistency, incompleteness, or deception inherent in big data? Volume None of the other choices Veracity Velocity Variety

Veracity

Scores on Ms. Bond's test have a mean of 70 and a standard deviation of 11. Michelle has a score of 48. Michelle's z-score (standardized score) on this test is ______. zero. a negative value equal to -2. a positive value equal to 2.

a negative value equal to -2.

The correlation coefficient will always take values between -1 and +1. greater than 0. between -1 and 0. less than -1.

between -1 and +1.

A __________ is a graphical summary of data previously summarized in a frequency distribution. box plot histogram line chart scatter chart

histogram

Corporate-level managers use ______ to gain insight about sales by region, current inventory levels, and other company-wide metrics all in a single screen. crosstabulation data journal tables data dashboards

data dashboards

The decisions concerning an organization's goals and future plans are called: strategic decisions. operational decisions. tactical decisions. financial decisions.

strategic decisions

If co-variance between two variables is negative, it implies that the variables are negatively related. a positive relationship exists between the variables. the variables are not linearly related. the co-variance cannot assume negative values.

the variables are negatively related.

Variance is a measure of ___________. Unlike the range, variance utilizes __________ the data. variability - all variability - some location - all location - some

variability - all