Chapter 11: Understandign Statistics In Reaseach

Question 1

What theory is used to explain a relationship, the probability of an event occurring in a given situation, or the probability of accurately predicting an event ?

(Key points)

Answer 1

Probability theory

Question 2

What theory assumes that all the groups in a study used to test a particular hypothesis are components of the same population in relation to the study variables

(Key points)

Answer 2

Decision theory

Question 3

What error occurs when the null hypothesis is rejected, although it is true. The researchers
conclude that significant results exist in a study, when in reality they do not. The risk of this type is indicated by the level of significance (a). (False positive)

(Key points)

Answer 3

Type I

Question 4

What error (β) occurs when the null hypothesis is accepted when it is actually false. The re-
searchers conclude that the study results are nonsignificant when the results are significant.
This errors often occur because of flaws in the research methods, and their risk can be exam-
ined using power analysis. (False negative)

(Key points)

Answer 4

Type II

Question 5

Quantitative data analysis includes the following steps: (5)

Key points

Answer 5

(1) management of missing data;
(2) description of the study sample;
(3) examination of the reliability of measurement methods;
(4) performance of exploratory analyses of the data; and
(5) conduct of inferential analyses guided by the hypotheses, questions, or objectives.

Question 6

Which statistic includes frequency distributions, percentages, measures of central tendency, measures of dispersion, and scatterplot they are calculated to describe the sample and key study variables.
(Key points)

Answer 6

Descriptive or summary statistics

Question 7

Which analysis was conducted to examine relationships that are covered in this text include
Pearson product-moment correlation and factor analysis.

(Key points)

Answer 7

Statistical

Question 8

Which analysis is conducted to predict the value of one dependent variable using one or
more independent variables.

(Key points)

Answer 8

Regression analysis

Question 9

Which analyses is conducted to examine group differences and determine causality included in
this text are the chi-square test, t-test, ANOVA, and ANCOVA.

(Key points)

Answer 9

Statistical

Question 10

Interpretation of results from quasi-experimental and experimental studies is traditionally
based on decision theory, with five possible results:

(Key points)

Answer 10

(1) significant results predicted by the researcher;
(2) nonsignificant results;
(3) significant results that are opposite from those predicted by the researcher;
(4) mixed results; and
(5) unexpected results.

Question 11

What usually includes findings, significance of findings, limitations, conclusions,
generalization of findings, implications for nursing, and recommendations for further studies.

(Key points)

Answer 11

Research outcomes

Question 12

When should you evaluate the appropriateness and completeness of the
researchers’ results and discussion sections ?

(Key points)

Answer 12

In critically appraising a study

Question 13

Is a theoretical frequency distribution of all possible values in a population.

Answer 13

Normal curve

Question 14

In a normal distribution curve what is equal?

Answer 14

The mode, mean, and median

Question 15

What is based on the logic of the normal curve

Answer 15

Levels of significance and probability

Question 16

What is calculated based on the theory of the normal curve

Answer 16

The probability that any data score will be within a certain range of a mean value

Question 17

is referred to as alpha (a) which is the probability level at which the results of statistical analysis are judged to indicate a status ally significant difference between the groups.

Answer 17

Level of Significance (the cutoff point) :cutoff point

Question 18

Two-tailed test of significance =

Answer 18

the analysis of nondirectional hypothesis

Question 19

One-tailed test of significance =

Answer 19

the analysis of directional hypothesis

Question 20

Which tailed statistic test is uniformly more powerful

Answer 20

One-tailed

Question 21

There is a greater risk of a type I error with:

Answer 21

A 0.05 level of significance (5 errors in 100) than with a 0.01 level of significance (1 chance for error in 100)

Question 22

There is a greater risk of a type II error when:

Answer 22

The significance if 0.01 than when it is 0.05

Question 23

is the probability that a statistical test will detect a significant difference if one exists (The probability of correctly rejecting H0= 1-β (power).

Answer 23

Power

Question 24

What can be determined using power analysis ?

Answer 24

The risk of a type II error

Question 25

What are the four parameters of a power analysis:

Answer 25

1. The level of significance (α = 0.05)
2. Sample size
3. Power (minimum acceptable power is = 0.80 (80%)
4. Effect size (> 0.50 : large)

Question 26

Describes the occurrence of scores or categories in a study

Answer 26

Frequency distribution

Question 27

Types of frequency distribution

Answer 27

1. Ungrouped frequency distribution: in which a table is developed to display all numerical values obtained for a particularvariable. This approach is generally used on discrete rather than continuous data. Examples of data commonly organized in this manner are gender, ethnicity, marital status, diagnoses of study participants, and values obtained from the measurement of selected research and dependent variables.
2. Grouped frequency distribution : are used when continuous variables are being examined. Many
   measures taken during data collection, including body temperature, vital lung capacity, weight
   age, scale scores, and time, are measured using a continuous scale.
3. Percentage distribution: indicates the percentage of study participants in a sample whose scores
   fall into a specific group and the number of scores in that group, Percentage distributions are par
   ticularly useful for comparing the present data with findings from other studies that have difleren
   sample sizes.

Question 28

What were the measured of central tendency

Answer 28

1. The mean, used only for ratio/interval data, is the average of all values. Outliers do affect the mean value.
2. The median, used for ordinal data, is the middle value. If n is an even number, there are two middle values; their average is the median. Outliers do not affect the median value.
3. The mode, used for nominal data, is the most commonly occurring value. There may be more than one mode, of course. Outliers do not affect the mode.

-In a perfectly normal distribution, the mean is also the median, and is also the mode.

Question 29

What are the measures of dispersion:

Answer 29

1. Range: is obtained by subtracting lowest score from the highest score
2. Variance: indicates the spread of dispersion of the score
3. Standard deviation: the square root of the calculated value of the variance, indicates the average difference between each data point and the mean of a data set.
4. Confidence interval: when the probability of including the value of the population within an interval estimate is known
5. Standardized scores: expressed raw scores as deviations from the mean, so that scores across different instruments can be compared: GPA verses SAT, for instance Raw scores that cannot be compared and are transformed into standardized scores,Common standardized score is a Z-score
6. Scatterplot: is a visual representation of data, on a scaled graph, with two axes. Used to display matched values- height versus weight, for instance. Unless drawn to scale, a scatterplot is only fairly good at displaying dispersion, and provides no quantification

Question 30

are used to test an actual or implied hypothesis emanating from the research purpose – those testing relationships and difference are the primary ones. Infer or address objectives, questions, and hypothesis

Answer 30

Inferential statistics

Question 31

What statistics test are conducted to examine differences

Answer 31

Chi-square test
T-test
Analysis of variance (ANOVA)

Question 32

Determines wether two variables are independent or related; test can be used with nominal or ordinal

Answer 32

Chi square test

Question 33

One of the most common analysis conducted to test for significan differences between two samples is …

Answer 33

The t-test

Question 34

Is a parametric statistical technique conducted to examine differences among three or more groups

Answer 34

ANOVA

Question 35

Statistics that are conducted to predict outcomes

Answer 35

Regression analysis

Question 36

Is used to predict the value of one variable when the value of one or more other variables is known

Answer 36

Regression analysis

Question 37

Statistics conducted to examine relationships:

Answer 37

Pearson product-moment correlation

Factor analysis

Question 38

Is an inferential analysis technique conducted to e mine bisaría te correlations in studies

Answer 38

Person product-moment correlation

Question 39

Commonly conducted to examine the interrelationships among large numbers of items on a scale and disentangles those relationships to identify clusters of items that are most closely linked

Answer 39

Factor analysis