Stats Final

A numerical measure computed from a sample, such as sample mean, is known as

Sample statistic

A probability sampling method in which we randomly select one of the first k elements and then select every kth (n/N) element thereafter is

Systematic Sampling

If a set has an even number of observations, the median is

The average value of the two middle items when all items are arranged in ascending order

If the data distribution is symmetric, the skewness is

0

The range of probability is

0 to 1, inclusive

The probability of the intersection of two mutually exclusive events

Must always be equal to 0

Two approaches to drawing a conclusion in a hypothesis test are

p-value and critical value

The form of the continuous uniform probability distribution is

rectangular

The difference between the value of the sample statistic and the value of the corresponding population parameter is called the

sampling error

The probability of at least one head in two flips of a coin is

.75

For any continuous random variable, the probability that the random variable takes on exactly a specific value is equal to __________.

0

The t value with 95% confidence and 24 degrees of freedom is

2.064

An experiment consists of three steps. There are four possible results on the first step. Three possible results on the second step, and two possible outcomes on the third step. The total number of experiment outcomes is

24

A magician holds a standard deck of cards and draws one card. The probability of drawing the ace of diamonds is 1/52. What method of assigning probabilities was used

Classical Method

A nonprobability sampling where the sample is selected because it is relatively easy is

Convenience sampling

Data collected at the same, or approximately the same, point in time are _______ data

Cross- sectional

A tabular method that can be used to summarize the data on two variables simultaneously is called

Crosstabulation

The summaries of data, which may be tabular, graphical, or numerical, are referred to as

Descriptive Statistics

The ______ denotes the number of standard deviations Xi is from the mean

Z-score

A Type I error is committed when

a true null hypothesis is rejected

statistical inference

the process of drawing inferences about the population based on information taken from the sample

Larger values of the standard deviation result in a normal curve that is

wider and flatter

The sum of the relative frequencies for all classes will always equal

1

Which of the following values of r indicates the strongest correlation

-.9

An important numerical measure related to the shape of a distribution is the

Skewness

The correlation coefficient ranges from which two values

-1 to +1

Read the t statistic from the table of t distributions and circle the correct answer. A one-tailed test (lower tail), a sample size of 10 at a .10 level of significance; t =

-1.383

A probability sampling in which we randomly select elements within each homogenous group is

Stratified random sampling

For the standard normal probability distribution, the area to the left of the mean is

0.5

The finite correction factor should be used when n/N is greater than

.05

A frequency distribution is a

Tabular summary of a set of data showing the number of items in each of several nonoverlapping classes

A mean computed in such a way that each value is given a weight reflecting its importance is referred to as a

Weighted Mean

There is a 60% chance of getting stuck in traffic when leaving the city. On two separate days what is the probability that you get stuck in traffic both days

.36

Of five letters (A, B, C, D, E) two letters are to be selected at random. How many possible selections are there

10

The "top three" at a racetrack consists of picking the correct order of the first three horses in a race. If there are 10 horses in a particular race, how many outcomes are there

720

Twenty percent of people at a company got food poisoning. What percent of the people did not get food poisoning.

80%

An interval estimate is used to estimate

A Population Parameter

The number of costumers who enter a store during one day is an example of

A discrete random variable

If you are conducting an experiment where the probability of a success is .02 and you are interested in the probability of two successes in 15 trials, the correct probability function to use is the

Binomial probability function

A theorem that allows us to use the normal probability distribution to approximate the sampling distribution of sample means and sample proportions whenever the sample size is larger is known as the

Central Limit Theorem

If arrivals follow a Poisson probability distribution, the time between successive arrivals must follow

Exponential

There is a lower limit but no upper limit for a random variable that follows the _________ probability distribution

Exponential

When sampling without replacement, the probability of obtaining a certain sample is best given by a ( uniform / binomial / Poisson / hypergeometric ) distribution.

Hypergeometric distribution

When the data have the properties of ordinal data and the interval between observations is expressed in terms of a fixed unit of measure, the variable has which scale of measurement? (example-Temperature)

Interval

The coefficient of variation indicates how large the standard deviation is relative to the

Mean

After the data have been arranged from smallest to largest, the value in the middle is called the

Median

The 50th percentile is the

Median

When the data are labels or names used to identify attribute of the elements, the variable has which scale of measurement (example- Gender)

Nominal

The mean, median, mode have the same value for which of the following distributions

Normal

As the degrees of freedom increase, the t distribution approaches the

Normal distribution

When the data are labels or names used to identify an attribute of the elements and the rank of the data is meaningful, the variable has which scale of measurement (example- Class Standing)

Ordinal

Excel's __________ can be used to construct a crosstabulation.

PivotTable Report

In the textile industry, a manufacturer is interested in the number of blemishes or flaws in each 100 ft of material. The probability distribution that has the greatest chance of applying to this situation is the

Poisson

The random variable x is the number of occurrences of an event over an interval of 10 minutes. It can be assumed the probability of an occurrence is the same i n any two time periods of equal length. It is known that the mean number of occurrences in 10 minutes is 5.3. The random variable x satisfies which of the following probability distributions

Poisson

A numerical measure, such as a mean, computed from a population is known as a

Population Parameter

_____ analytics consists of analytical techniques that use models constructed from past data to predict the future or to assess the impact of one variable on another

Predictive

The measure of dispersion that is influenced most by extreme values is the

Range

when the data have the properties of interval data and the ratio of two values is meaningful, the variable has which scale of measurement? (example- Heights)

Ratio

When the results of experimentation or historical data are used to assign probability values, the method used to assign probabilities is referred to as the

Relative Frequency method

Excel's _____ function can be used to compute the expected value of a discrete random variable

SUMPRODUCT

The height and weight are recorded by the school nurse for every student in a school. What type of graph would best display the relationship between height and weight

Scatter diagram

A two-tailed test is performed at 5% level of significance. The p-value is determined to be 0.09. The null hypothesis

Should not be rejected

The highest point of a normal curve occurs at

The mean

The sum of frequencies for all classes will always equal

The number of elements in a data set

Which of the following is an example of quantitative data

The number of people in a waiting line

The collection of all possible sample points in an experiment

The sample space

For a standard distribution, a negative value of z indicates

The z is to the left of the mean

Data collected over several time periods are ______ data

Time series

The relative frequency of a class is computed by

dividing the frequency of the class by the sample size

as sample size increases the

standard error of the mean decreases