Flashcards in Unit 3 Deck (37):

1

## In a normal curve, the inflection points occur at ____.

### Μ ± 1σ

2

## Given below are lower and upper limits of areas of the normal curve. Choose the limits that mark off the greatest proportion of the normal curve.

### -lσ to 1σ

3

### -lσ to 0

4

## You have just received your psychology exam grade and you did better than the mean of the exam scores. If so, the z transformed value of your grade must

###
must be greater than 0.00 and

have a percentile rank greater than 50%

5

## Associated with a point of inflection on a normal curve is

### one standard deviation

6

## A testing service has 1000 raw scores. It wants to transform the distribution so that the mean = 10 and the standard deviation = 1. To do so, ____.

###
Do a z transformation for each raw score and add 10 to each z score. and

Divide each deviation score by the standard deviation of the raw scores. Take this result for all scores and add 10 to each one.

7

## Would you rather have an income (assume a normal distribution and you are greedy) ____.

### with a z score of 1.96

8

## Another name for a z score is

### standard score

9

## Under what circumstances would a score that is 15 points above the mean be considered to be near the center of the distribution?

### when the population standard deviation is much larger than 15

10

## Approximately what percentage of scores fall between z = 1 and z = 1.5?

### 9%

11

## A population of scores has = 42. In this population, an X value of 40 corresponds to z = 0.50. What is the population standard deviation?

### 4

12

##
Data Set 4-3: -2, -1, 0, 2, 6

A raw score of -2 in Data Set 4-3 has a z score of

### -1.06

13

##
Data Set 4-4: 2, 4, 6, 8

For the population Data Set 4-4 a raw score of 6 has a z score of

### 0.45

14

##
Data Set 4-1: 2, 7, 3, 6, 2

For population Data Set 4-1 a raw score of 7 has a z score of

### 1.43

15

## Approximately what percentage of scores fall between z = 0 and z = .5?

### 19%

16

## A population of scores has = 20. In this population, a score of X = 80 corresponds to z = +0.25. What is the population mean?

### 75

17

##
Data Set 4-3: -2, -1, 0, 2, 6

A raw score of 6 in the population Data Set 4-3 has a deviation score of

### 5

18

## For any normal distribution, what is the probability of selecting a score less than the mean?

### 50%

19

## Suppose that Graduate Record Examination (GRE) scores are normally distributed with a mean Μ = 500 and standard deviation σ = 100. What is the z score that corresponds to a GRE score of 600?

### 1

20

## Let's assume that the scores are normally distributed on a test with a population mean of 75 and standard deviation equal to 16. What is the percentile rank of a score of 56?

### 11.7

21

## Suppose that Graduate Record Examination (GRE) scores are normally distributed with a mean Μ = 500 and standard deviation σ = 100. What is the z score that corresponds to a GRE score of 350?

### -1.5

22

## The advantage of using z scores over using raw scores is that z scores allow you to

###
compare a score in one distribution to a score in another and

understand the relationship of a score to the mean

23

## A z-score of z = +3.00 indicates a location that is __________.

### far above the mean in the extreme right-hand tail of the distribution

24

## The theoretical normal distribution has

### parameters

25

## What two parameters of a population must be known in order to use the normal curve table?

### mean and standard deviation

26

## Which of the following is a characteristic of a normal distribution?

### symmetric, unimodal, asymptotic

27

## The standard normal distribution is a ____ distribution with μ = ____ and σ = ____.

### normal, 0, 1

28

## The theoretical normal curve has a mean equal to __________ and a standard deviation equal to __________.

### 0, 1

29

## What proportion of the scores in a normal distribution fall below z = –1.32?

### 0.0934

30

## What proportion of a normal distribution is located in the tail beyond a z-score of z = 1.50?

### 0.0668

31

## For a normal distribution with mean of 75 and standard deviation of 25, the proportion of the scores between 90 and 100 is

### .1156

32

## A testing bureau reports that the mean for the population of Graduate Record Exam (GRE) scores is 500 with a standard deviation of 90. The proportion of scores that lie above 650 is ____.

### 0.0475

33

## Scores on the Math Achievement Test form a normal distribution with a mean of = 300 and a standard deviation of = 100. What score separates the top 10% of the distribution from the rest?

### 428

34

## A stockbroker has kept a daily record of the value of a particular stock over the years and finds that prices of the stock form a normal distribution with a mean of $8.52 with a standard deviation of $2.38. The percentage of scores that lie between $9.00 and $10.00 is ____.

### 15.31%

35

## SAT scores form a normal distribution with a mean of = 500 and a standard deviation of = 100. The probability of randomly selecting an SAT score greater than 450 is __________.

### 0.6915

36

## A normal distribution has a mean of = 60 with = 8. What is the probability of selecting an individual with a score greater than 54?

### 0.7734

37