Question 1

___________ __________ is defined as the condition of having normally distributed data in each data group.

Accepted Answer

Equal variance is the condition where each group in a dataset has a normal distribution with the same variance, ensuring homogeneity of variances across groups. This is important in statistical analyses like ANOVA.

Question 2

A ________ ___________ is defined as the strength of evidence to support the null hypothesis or how likely the difference between the two groups could have happened by accident.

Accepted Answer

The p-value is a measure that indicates the strength of evidence against the null hypothesis. It quantifies how likely the observed data would be if the null hypothesis were true, essentially assessing the probability that any observed difference between groups occurred by chance.

Question 3

When the p-value is less than ________, there is strong evidence to reject the null hypothesis.

Accepted Answer

The standard threshold for rejecting the null hypothesis in many scientific studies is a p-value of less than 0.05, indicating strong evidence against the null hypothesis.

Question 4

Which test do investigators use when their null hypothesis reflects a specific direction?

Accepted Answer

Investigators use a one-tailed test when their null hypothesis reflects a specific direction because it tests for the possibility of the relationship in one direction and completely disregards the possibility of a relationship in the other direction.

Question 5

What percentage of the total possible values are found beneath a normal curve?

Accepted Answer

100% of the total possible values are found beneath a normal curve, as it encompasses all possible outcomes within its range.

Question 6

The percentage points used in inferential statistics to reject or fail to reject the null hypothesis are called:

Accepted Answer

Critical values are the threshold values that are compared with the test statistic to decide whether to reject the null hypothesis in inferential statistics. They are determined by the significance level (alpha) and the distribution of the test statistic.

Question 7

The two types of t-tests are:

Accepted Answer

The two types of t-tests are independent and paired samples. Independent samples t-tests compare the means of two independent groups, while paired samples t-tests compare means from the same group at different times or under different conditions.

Question 8

What test is used to compare the mean scores of one group tested twice?

Accepted Answer

The paired-samples t-test is used to compare the means of one group on two different occasions or under two different conditions, making it the correct choice for comparing mean scores of one group tested twice.

Question 9

The magnitude of the difference between the mean scores of the null hypothesis is estimated by:

Accepted Answer

The confidence interval estimates the range within which the true difference between the mean scores of the null hypothesis is likely to fall, thus providing an estimate of the magnitude of that difference.

Question 10

What type of test is used to compare the mean scores of two groups tested once?

Accepted Answer

An independent t-test is used to compare the mean scores of two different groups of subjects to see if there is a significant difference between them. This test is appropriate when each group of subjects is tested once, and the groups are independent of each other.

Question 11

When using a two-tailed test, the normal curve is divided into three sections.

Accepted Answer

In a two-tailed test, the normal curve is divided into three sections: the two tails, which represent the extreme ends where the null hypothesis may be rejected, and the middle section, which represents the range of values where the null hypothesis is not rejected.

Question 12

The data used for a chi-square test are called nonparametric data.

Accepted Answer

Nonparametric data, also known as categorical or nominal data, are used in a chi-square test, which does not assume a normal distribution of the variables.

Question 13

Degrees of freedom are defined as the number of choices, minus one for the overall category.

Accepted Answer

Degrees of freedom typically refer to the number of independent values or quantities which can be assigned to a statistical distribution, minus one to account for constraints such as the overall total or mean. This concept is used to determine the number of independent pieces of information in a dataset that are free to vary.

Question 14

If a statistical test is performed, that means we know with certainty that the hypothesized relationship exists.

Accepted Answer

A statistical test assesses the likelihood of a hypothesized relationship under certain assumptions, but it does not provide certainty. It evaluates whether the observed data could reasonably occur by chance if the null hypothesis were true.

Question 15

Wide dispersion of data means greater strength.

Accepted Answer

Wide dispersion of data indicates greater variability, not necessarily greater strength. It means the data points are spread out over a wider range, which can imply inconsistency or variability in the measurements or observations.

Question 16

If a t-test is used, the mean score is always derived from the whole population.

Accepted Answer

A t-test often uses sample means to make inferences about the population mean, not the mean of the entire population.

Question 17

Correlation does not mean that one variable causes another variable to change, but simply means that two things are numerically related or associated.

Accepted Answer

Correlation indicates a statistical relationship between two variables, but it does not imply causation. Two variables can be correlated without one causing the other to change.

Question 18

There are two basic types of statistics: ______________ and _____________.

Accepted Answer

The answer of There are two basic types of statistics:...

Question 19

_____________ is a branch of mathematics that focuses on data collection, analysis, and interpretation of data.

Accepted Answer

The answer of _____________ is a branch of mathematics that...

Question 20

_______________ statistics organize and summarize data without the use of complicated mathematical equations, while _____________ statistics emphasizes identifying associations and drawing conclusions about a population from a random sample of data taken from that population.

Accepted Answer

The answer of _______________ statistics organize and summarize data without...

Quiz 13: Inferential Statistics

_ is defined as the condition of having normally distributed data in each data group.

A ___ is defined as the strength of evidence to support the null hypothesis or how likely the difference between the two groups could have happened by accident.