Bus. analytics exam 1

In a random sample of 400 registered voters, 120 indicated they plan to vote for the Republican Party. Determine a 95% confidence interval for the proportion of all the registered voters who will vote for the Republican Party. ​

(0.255, 0.345)

The simplest measure of variability is the

. range

______________ analytics are techniques that use models, constructed from past data, to predict the future or to ascertain the impact of one variable on another.

. ​Predictive Correct

A _____ is a line that provides an approximation of the relationship between the variables. line chart sparkline trendline gridline

Trendline

A time series plot is also known as a

line chart

A simple random sample of size n from a finite population of size N is a sample selected such that each possible sample of size

n has the same probability of being selected

A forecast that helps direct police officers to areas where crimes are likely to occur based on past data is an example of

predictive analytics.

A ___________ is used to visualize sample data graphically and to draw preliminary conclusions about the possible relationship between the variables. Select one:

scatter chart

Simulation optimization helps

to find good decisions in highly complex and highly uncertain settings.

The goal regarding using an appropriate number of bins is to show the

variation in the data.

Using an α = 0.04 a confidence interval for a population proportion is determined to be 0.65 to 0.75. If the level of significance is decreased, the interval for the population proportion

​becomes wider.

What would be the value of the sum of squares due to regression (SSR) if the total sum of squares (SST) is 25.32 and the sum of squares due to error (SSE) is 6.89?

18.43

In order to determine an interval for the mean of a population with unknown standard deviation a sample of 24 items is selected. The mean of the sample is determined to be 23. The number of degrees of freedom for reading the t value is

23

If the expected value of the sample statistic is equal to the population parameter being estimated, the sample statistic is said to a. have low variability. b. be an unbiased estimator of the population parameter. c. have high precision. d. be a random estimator of the population parameter.

Be an unbiased estimator of the population parameter

If the scatter chart indicates a positive linear relationship between two variables, then their correlation coefficient is: equal to -1. greater than 1. between 0 and +1. between -1 and 0.

Between 0 and +1

In order to visualize three variables in two-dimensional graph, we use a 2-D chart. 3-D chart. bubble chart. column chart.

Bubble chart

Natalie needs to compare the number of employees by job title for the last five years. Which of the following charts should Natalie use? ​​

Clustered-column (bar) chart

A fast food restaurant has automatic drink dispensers to help fill orders more quickly. When the 12 ounce button is pressed, they would like for exactly 12 ounces of beverage to be dispensed. There is, however, undoubtedly some variation in this amount. The company does not want the machine to systematically over fill or under fill the cups. Which of the following gives the correct set of hypotheses

H0: U = 12, Ha : U ≠ 12

The CEO of a company wants to estimate the percent of employees that use company computers to go on Facebook during work hours with 95% confidence. He selects a random sample of 150 of the employees and finds that 53 of them logged onto Facebook that day. What is the estimate of the standard error of the proportion

Need this formula Squareroot of (population proportion (1-pop proportion) / n)

A crosstabulation in Microsoft Excel is known as a scatter plot. bar chart. histogram. PivotTable.

Pivot table

A simple random sample of 31 observations was taken from a large population. The sample mean equals 5. Five is a a. population parameter. b. point estimate. c. population mean. d. standard error.

Point estimate

____ is a statistical procedure used to develop an equation showing how two variables are related.

Regression analysis

which statement is NOT true: a. The greater the level of confidence, the more likely it is that the confidence interval actually includes the true population mean. b. The greater the level of confidence, the larger the z-score. c. The greater the level of confidence, the wider the confidence interval. d. Rejecting the null hypothesis when it is true is a Type II error.

Rejecting the null hypothesis when it is true is a Type II error.

A variable used to model the effect of categorical independent variables in a regression model which generally takes only the value zero or one is called

a dummy variable.

The ______________________ shows the number of data items with values less than or equal to the upper class limit of each class.

a. cumulative frequency distribution

A statistics teacher started class one day by drawing the names of 10 students out of a hat and asked them to do as many pushups as they could. The 10 randomly selected students averaged 15 pushups per person with a standard deviation of 9 pushups.Suppose the distribution of the population of number of pushups that can be done is approximately normal. What is the standard error of the mean?

b. ​2.876

As the number of degrees of freedom for a t distribution increases, the difference between the t distribution and the standard normal distribution

becomes smaller

For data having a bell-shaped distribution, approximately _____ percent of the data values will be within one standard deviation of the mean. Select one:

c. 68 Correct

When a decision maker is faced with several alternatives and an uncertain set of future events, s/he uses ______ to develop an optimal strategy.

d. decision analysis Correct

The process of making conjecture about the value of a population parameter, collecting sample data that can be used to assess this conjecture, measuring the strength of the evidence against the conjecture that is provided by the sample, and using these results to draw a conclusion about the conjecture is known as

hypothesis testing.

A one-tailed test is a hypothesis test in which the rejection region is

in one tail of the sampling distribution

Deleting the grid lines in the table and the horizontal lines in the chart : increases the data-ink ratio. decreases the data-ink ratio. increases the Non-data-ink ratio. does not affect the data-ink ratio.

increases the data-ink ratio.