Midterm

Question 1

A number that characterizes the population is a

Answer 1

Parameter

Question 2

What is the larger group of cases in which a researcher is interested?

Answer 2

Population

Question 3

When should you worry about confounding variables?

Answer 3

In any experimental design

Question 4

A number that characterizes a sample is a

Answer 4

Statistic

Question 5

What is the biggest advantage of a correlational design?

Answer 5

It allows researchers to study relationships between variables as they exist in real life

Question 6

Numbers _____ in how much information they contain

Answer 6

Numbers vary in how much information they contain

Question 7

Which of these do statistics do?

Answer 7

They bring order to chaos

Question 8

___ reveal whether cases posses more or less of some characteristic

Answer 8

Ordinal-level numbers

Question 9

The statement “The average american household has $6969 in credit card debt” is an example of

Answer 9

A descriptive statistic

Question 10

The variable that’s manipulated by the researcher is the what?

Answer 10

Independent variable

Question 11

One can draw cause and effect conclusions with an experimental design when groups differ on the dependant variable and

Answer 11

The only difference between the groups is the independent variable

Question 12

An inferential statistic

Answer 12

Uses a sample of cases to draw a conclusion about the larger population

Question 13

Sample is to statistic as population is to ___

Answer 13

parameter

Question 14

The subjects of a study are called what

Answer 14

cases

Question 15

A grouped frequency table can only be used if

Answer 15

the intervals are of equal width

Question 16

Ungrouped frequency tables work well when the

Answer 16

variable can have only a limited set of values

Question 17

A frequency distribution is a

Answer 17

count of how often the values of a variable occur in a set of data

Question 18

Which of these could be best represented using a grouped frequency distribution?

Answer 18

Salaries for first jobs of all graduating college students

Question 19

Percentages are useful because

Answer 19

They can transform scores by putting them into context

Question 20

Theoretically, _____ can be made more exact by using more precise measuring instruments

Answer 20

continuous numbers

Question 21

_____ answer the question “how many?”

Answer 21

Discrete numbers

Question 22

Nominal and ordinal level data are ____ and should be graphed with a ______

Answer 22

Nominal and ordinal level data are discrete and should be graphed with a bar graph

Question 23

When creating a bar graph, the ____ goes on the Y axis

Answer 23

frequency

Question 24

Knowing the shape of a distribution is important because:

Answer 24

the shape will determine whether certain statistics can be used

Question 25

A distribution is considered skewed if it

Answer 25

is not symmetrical

Question 26

What describes whether the data set us peaked or flat?

Answer 26

Kurtosis

Question 27

Why is it important to report both a measure of central tendency and variability to describe a set of scores?

Answer 27

Sets of data with the same central tendency may have different patterns of variability

Question 28

A measure of central tendency is used to describe the

Answer 28

typical or average score in a set of scores

Question 29

One advantage of the median over the mean is that the median

Answer 29

is not as affected by the presence of outliers in a data set

Question 30

If the mean is quite a bit smaller than the median, the distribution is likely

Answer 30

negatively skewed

Question 31

The sum of a set of deviation scores will

Answer 31

always be equal to 0

Question 32

Nominal level data; use mean, median, or mode?

Answer 32

Mode

Question 33

A hypothesis is a

Answer 33

proposed explanation for observed facts

Question 34

The value that the test statistic must meet or exceed in order to reject the null hypothesis is the

Answer 34

critical value

Question 35

What does p < .05 mean?

Answer 35

The same results will be seen in less than 5% of the time if the null hypothesis is true

Question 36

A same mean would be statistically significant if

Answer 36

it fell in the rare zone

Question 37

Give an example of a question that would require a single-sample z test

Answer 37

Does a sample of purebred dogs live longer than dogs in general?

Question 38

Which of these outcomes indicates that a researcher made a type II error?

Answer 38

Dr ross failed to reject the null hypothesis when an experimental treatment worked

Question 39

If a researcher should say something happened but doesn't, then the researcher had committed a

Answer 39

Type 2 error

Question 40

Which of these outcomes indicates the researcher made a type I error?

Answer 40

Dr ross rejected the null hypothesis when an experimental treatment didn't work

Question 41

If one failed to reject the null hypothesis, one needs to consider the possibility that

Answer 41

A type II error was made

Question 42

If consent rates are below 70%, there may be a concern that there is ____ in the study

Answer 42

a self-selection bias

Question 43

Having a representative sample is important because it makes the

Answer 43

results from that study more generalizable

Question 44

A ____ is a range based on a sample value, within which it's estimated that a population value falls

Answer 44

confidence interval

Question 45

The CLT only works when

Answer 45

the sample is over 30

Question 46

When the SE of the mean is small, the ____ more accurately reflects the ____

Answer 46

sample mean; population mean

Question 47

A ____ sample size is more likely to have a smaller standard error

Answer 47

larger

Question 48

If sam opens 500 diff bags of candies and then creates a histogram of the percent of green candies in each bag, what had sam created?

Answer 48

a sampling distribution

Question 49

The CLT describes the ____ of the means calculated when the samples are large and every possible sample is attained

Answer 49

shape of the sampling distribution

Question 50

In a distribution of z scores, the SD will

Answer 50

always b 1.00

Question 51

The mean of a distribution of z scores will

Answer 51

always be 0.00