Question 1

In the statistical expression "p < .05," the "p" represents

Accepted Answer

In statistical hypothesis testing, the "p" value represents the probability of obtaining results similar to the obtained results by chance alone. A value of less than .05 (or 5%) indicates that the results are statistically significant and unlikely to have occurred by chance, allowing researchers to reject the null hypothesis.

Question 2

Which of the following is an example of an inferential statistic?

Accepted Answer

The p value from a statistical test is an example of an inferential statistic as it allows for making conclusions about a population based on a sample.

Question 3

What does it mean to say that "p < .05"?

Accepted Answer

"p < .05" means that the probability of getting such a pattern of results by accident is less than 5%. It is a common criterion used in statistical hypothesis testing to determine whether to accept or reject a null hypothesis. If the p-value is less than .05, it is considered statistically significant, which means that the results are unlikely to be due to chance.

Question 4

A particular research study compares an experimental group with a control group.An analysis of the results reveals that "p < .05." Therefore,

Accepted Answer

When "p < .05", it means that there is less than a 5% chance of obtaining the observed difference between the experimental and control groups by chance. This is the standard level of significance used in many research studies.

Question 5

An investigator wishes to determine whether the difference between two groups of participants is statistically significant.To answer that question,the investigator must first determine the difference between the means of the two groups,the number of participants in each group,and

Accepted Answer

The amount of variation in each group, typically measured by the standard deviation or variance, is necessary to determine the statistical significance of the difference between the means of the two groups. The age of participants, duration of the experiment, and strength of motivation may be important for other aspects of the study, but they are not directly related to determining the significance of the difference between the two groups.

Question 6

The mean,median,range,and standard deviation are all examples of

Accepted Answer

The mean, median, range, and standard deviation are all examples of descriptive statistics, which are used to summarize and describe characteristics of a data set. Inferential statistics involve making predictions or drawing conclusions about a population based on a sample, correlations involve measuring the strength and direction of a relationship between two variables, and tests of significance involve determining the probability of obtaining a particular result by chance.

Question 7

Which of the following would (as a rule)indicate that a result is statistically significant?

Accepted Answer

A result is considered statistically significant if the p-value is less than .05. This means that there is a less than 5% chance that the observed result occurred by chance alone. The other options do not indicate statistical significance.

Question 8

The statement "p < .05" refers to

Accepted Answer

"p < .05" is a commonly used cutoff for statistical significance in psychology research. It means that there is a less than 5% chance that the results obtained are due to chance and not a true effect. In other words, the statement is referring to the probability of getting a result by chance.

Question 9

A psychologist conducts an experiment and reports that p < .05.What is the relationship between the value of p and the statistical significance of the results?

Accepted Answer

A p value less than .05 indicates that there is less than a 5% chance that the results occurred by random chance. Therefore, the results are considered statistically significant and there is evidence to reject the null hypothesis. The lower the value of p, the more significant the results are.

Question 10

An investigator analyzes the results of an experiment and determines that p < .05.Why does the investigator want to know the value of p?

Accepted Answer

The value of p is used to determine whether the results of an experiment are statistically significant. A p-value of less than .05 indicates that there is a less than 5% chance that the results occurred by random chance alone and therefore, the results are statistically significant.

Question 11

An investigator decides to consider the results of an experiment to be statistically significant if p < .05.An analysis of the result indicates that p = .09.What conclusion,if any,can the investigator draw?

Accepted Answer

The investigator cannot draw any conclusion because the p-value is greater than the predetermined significance level of .05. This means that there is not enough evidence to reject the null hypothesis, and the results could be due to chance.

Question 12

Which of the following is used in calculating a standard deviation?

Accepted Answer

Standard deviation is a measure of how spread out a set of data is from the mean. In order to calculate the standard deviation, we need to know the mean of the data set. Therefore, the mean is necessary to calculate the standard deviation. The range, mode, and median are not directly used in calculating the standard deviation.

Question 13

A pre-school teacher records the height of all of her students and their parents.The distribution of these measures would be called a

Accepted Answer

A bimodal distribution is one where there are two distinct peaks or modes in the data. In this scenario, it would make sense for there to be two peaks - one for the heights of the preschoolers and one for the heights of their parents. A symmetrical distribution is one where the data is evenly distributed around a central value, which is unlikely in this case. A logarithmic distribution is one where the data is distributed in a logarithmic pattern, which is also unlikely in this scenario. A standard distribution is not a commonly used statistical term.

Question 14

The standard deviation is a statistic that measures

Accepted Answer

The standard deviation measures the amount of variation in a set of data. It tells us how spread out the values are from the mean.

Question 15

If the standard deviation is small,then

Accepted Answer

A small standard deviation indicates that the scores are clustered closely around the mean, so most scores are close to the mean.

Question 16

A survey asked how many sex partners you hope to have in the future.The majority of men answered 1,2,or 3,yet the mean was 64.How can that be?

Accepted Answer

The majority of men answered a lower number of sex partners, but the mean was influenced by a few individuals who reported very high numbers. This is an example of how outliers can strongly influence the mean in a skewed distribution.

Question 17

An investigator conducts a statistical test to determine whether the difference between the experimental group and the control group was statistically significant.Other things being equal,the difference is most likely to be significant if

Accepted Answer

If the mean of one group is much larger than the mean of the other group, then the difference between the groups is more pronounced and more likely to be statistically significant. A high standard deviation or small sample size can increase variability and make it more difficult to detect significant differences. If the mean for each group is about the same size as the standard deviation, the effect size may be small and less likely to be statistically significant.

Question 18

If p < .05,then the difference in results between the experimental group and the control group is probably

Accepted Answer

A p-value less than .05 indicates that the results are statistically significant, meaning that it is unlikely the difference between the groups occurred by chance. Therefore, the answer is C, statistically significant.

Question 19

If most scores are very close to the mean,then the standard deviation is

Accepted Answer

If most scores are very close to the mean, this means there is not a large amount of variability in the data. Therefore, the standard deviation will be very small.

Question 20

Mathematical summaries of results are called __________ statistics,while statistics that inform about the entire population,based on information collected from small samples,are called __________ statistics.

Accepted Answer

Descriptive statistics summarize data from a sample, such as mean or standard deviation, while inferential statistics use sample data to make generalizations about a larger population.

Quiz 2: Scientific Methods in Psychology