Statistics Chapter 2

Question 1

What is a sample?

Answer 1

A sample is a subset of people chosen from the population.

Question 2

How are samples used to make conclusions about populations?

Answer 2

Samples are used as a representation of the population.

Question 3

What are researchers really referring to when they talk about the population?

Answer 3

All relevant individuals in the world.

Question 4

What do you see when a relationship exists between two variables?

Answer 4

One would see a pattern as in scores in one variable change, the corresponding scores on the other variable change in a consistent t manner.

Question 5

What do you see when no relationship is present?

Answer 5

When there is no relationship, there is no consistent patterns between two variables.

Question 6

What does strength of a relationship refer to?

Answer 6

A consistent relationship between variables when Y score is paired with X score.

Question 7

What pattern in the Y scores will produce a weaker relationship?

Answer 7

As the scores of one variable change, the scores on the other variable tend to change in a consistent fashion; the less consistent the relationship, the weaker the relationship.

Question 8

What are the two aspects of a study to consider when deciding on the particular descriptive or inferential statistics that you should employ?

Answer 8

The design of the study and the scale of measurement used.

Question 9

What is the difference between an experiment and a correlation all study?

Answer 9

In an experiment, the researcher actively changes or manipulates one variable and then measures participants’ score on another variable to see if a relationship is produced. In a correlation all study, researchers measure participants’ scores on two variables and then determine whether a relationship is present.

Question 10

What is the difference between the independent variable and the conditions of an independent variable?

Answer 10

The independent variable is the overall variable the researcher is interested In; the conditions are the specific amounts or categories of the independent variable under which participants are tested.

Question 11

In an experiment, what is the dependent variable?

Answer 11

It is used to measure a participant’s behaviour under each condition, thus, the number of test errors is the dependent variable because we believe that errors depend on the a out of study.

Question 12

What is the general purpose of all research, whether experiments or correlation all studies?

Answer 12

To discover relationships between variables which may reflect how nature operates.

Question 13

What is descriptive statistics used for?

Answer 13

Descriptive statistics are used to summarize and describe the important characteristics of sample data and to predict an individual’s Y score based on his/her X score.

Question 14

What are inferential statistics use for?

Answer 14

Inferential statistics are for deciding whether to believe what the sample data indicate about the scores that would be found in the population.

Question 15

What is the difference between statistic and parameter?

Answer 15

Statistics describe a characteristic of a sample of scores. Parameters describes a characteristic of a population of scores.

Question 16

What type of symbols are used for statistics and parameters?

Answer 16

Statistics use letters from the English alphabet while parameters use letters from the Greek alphabet.

Question 17

Define the four scales of measurement.

Answer 17

• Nominal
• Ordinal
• Interval
• Ratio

Question 18

What are continuous and discrete variables?

Answer 18

The continuous scale allows for fractional amounts as it “continues” between the whole-number amounts, so decimals make sense. Discrete scale is measured only in whole amounts.

Question 19

A student named Foofy conducted a survey. In her sample, 83% of mothers employed outside the home would rather be home raising children. She concluded that “the statistical analysis prove that most working women would rather be at home.” What is the problem with this conclusion?

Answer 19

The problem is that statistical analysis cannot prove anything.

Question 20

Another student in your class, Poindexter, conducted a survey of college students about their favorite beverage. Based on what the sample said, he concluded that most college students prefer carrot juice to other beverage! What statistical argument can you give for not accepting this conclusion?

Answer 20

His sample is not representative of all college students. Perhaps he selected those few students who prefer carrot juice.

Question 21

List the scales of measurement, starting with the scale that proves the most precise information about the most variable present and ending with the scale that provides the least precise information.

Answer 21

Ratio scales provide the most specific information, interval scales, ordinal scale and the least most specific information is the nominal.

Question 22

What is a population?

Answer 22

A populations is a group of all individuals to which research applies.