RHIT 501
Research Methodology: Hypotheses
Formulating Hypotheses: The hypothesis is a researcher's tentative
explanation of professional opinion predicting the main results of the research
process. Supported by theory, research or personal experience, it states the
predicted results from the variables presented in the purpose statement.
The hypothesis usually presents a predicted outcome between two measures.
Since a number of measures may be involved, it is not unusual to include multiple
hypotheses, each predicting an expected outcome.
If there is no support for a proposed prediction, the statement of hypothesis is
frequently omitted.
Writing Hypotheses:
The three main types of hypotheses are:
-
The Null Hypothesis: this simply stated that no real relationship exists
among the variables. Unless statistically significant, differences in the
perceived relationship will be attributed to error or chance.
EX: No significant differences will be obtained between the sight
reading method and the phonics reading method in increasing
verbal comprehension scores.
-
Alternative non-directional hypothesis - an alternative non-directional
hypothesis states that there is a real difference among the variables or
groups, but the researcher is unsure of how the groups or variables
differ. Though we may be able to give a rationale fro differences
occurring, there is a stronger rationale for predicting that there is no
direction of outcome.
EX: Significant differences will be found between the sight reading
method and phonics reading method in increasing verbal
comprehension scores.
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Alternative directional hypothesis - states a specific relationship between
the variables or groups. A directional hypothesis includes one of two general
outcomes, either greater than or less than, but the outcomes may be
expressed by a variety of descriptors.
EX: The sight reading method will obtain significant increases in verbal
comprehension scores as compared to the phonics reading
method.
With all three types there is no statement of the population in the hypothesis
because it has already been given in the purpose statement.
Forms of Hypotheses: Once the type of hypothesis is determined the form of
the hypothesis can be selected.
There are five main forms:
scientific
research
statistical
theoretical
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-
educational
The first three forms usually refer to a hypothesis stated at a conceptual or
construct level.
Example (scientific):
No significant differences are to be found between relative
effectiveness of two types of incentives, praise and token on
cleaning productivity.
The research hypothesis is usually stated in terms of specifying the outcome
using the operationalized definition o the conceptual level variable.
Example (research):
Statistically significant increases in rate of rooms cleaned
productivity will be obtained for housekeepers who receive a day
off with pay (as an incentive) versus those housekeepers who
receive a written employee of the week reward (as an incentive).
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The statistical hypothesis is expressed in symbol form. Scientific hypotheses are
generally stated in the Introduction section with research and statistical
hypotheses stated in the Methods section.
Evaluating Hypotheses
The four criteria for writing and evaluating hypotheses are:
1
The hypothesis should be stated briefly and clearly. As in the
development of the purpose statement, the need to be as clear
as possible is also important.
EX: We hypothesize that no significant changes will be occurring with
fourth graders since it is our belief that if a loss of self-worth is
observed due to the achievement level grouping, it will be counter
balanced by an increase, since fourth grade students probably will
be more competitive within the achievement group class.
This hypothesis doesn't work because it attempts to imbed a rationale for the
hypothesis within the hypothesis itself.
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Consider this reworking:
No significant differences will be obtained between the average
achievement group and the low achievement group in decreasing level
of self-worth.
2
The hypothesis should express the relationship between
two variables.
Frequently a purpose statement expresses the relationship among multiple
variables. It is not unusual to have several hypotheses presented, all deriving
from one purpose statement. However, to ensure the reader comprehends the
predictions made, they need to be presented as an expressed relationship
between two variables.
Below is a statement of purpose that we will write hypotheses for:
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The main purpose of this study is to determine differences among levels of
anxiety (high, medium and low), in psychology students on measures of statistics,
development principles, learning theory, and research and evaluation concepts.
Levels of achievement (high, medium and low) are also examined.
A possible hypotheses for this is:
EX: High and low anxiety students, regardless of achievement level,
differ from medium anxiety psychology students and also differ if
they are high or low achievers on measures of statistics,
development and learning knowledge and concepts.
This non-directional alternative hypothesis presents several relationships among
multiple variables. The various relationships can be more clearly expressed as
multiple hypotheses. A suggested format for the hypothesis is to state a
comparison between two groups of levels of one variable and their relationship to
the second variable. Using the example we could rewrite it into nine different
hypotheses. In order to avoid redundancy and duplication we need to write the
hypothesis using the condition of comparison of two components of one variable
and their relationship to the second variable.
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Thus one hypothesis can be written to encapsulate several predictions:
EX: Significant differences will be obtained between the high and
medium anxiety groups on measures of statistics, developmental
principles and learning theory.
Write two more hypotheses for the purpose statement following the desired
format.
Writing hypotheses is like writing purpose statements, the appropriate general
conceptual level for a particular research study must be developed. It should not
be too specific, so as to avoid redundancy, but also not too general, so as to
produce ambiguity. Thus, for our sample purpose statement we produced three
hypotheses each predicting the relationship between two variables in three
different ways.
3
The hypothesis should be testable.
Consider the following two hypotheses:
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-
Feedback causes improvement.
-
Positive teacher comments will increase reading comprehension
scores when compared to neutral comments.
The first hypothesis is not testable. The second is reworded to express the
relationship between two levels of one variable (teacher comments - positive or
neutral) with a second variable (reading comprehension scores).
4
The hypothesis should be supported by a rationale derived
from theory, research or personal experience.
Developing hypotheses is a progression of different stages that vary in their
specificity.
A first step is usually based on intuition, experience or thought we have
had, it is therefore, some-what vague and ill-defined.
-
The second step is a period of incubation that includes gathering
information informally and reviewing past theories and research that
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seem to support our still hazy perspective.
-
The last step is one in which we clearly state our prediction and
rationale. Specific theoretical principles, research findings, or explicit
personal experiences have been manifested which facilitate the
development of the initial intuition.
Levels of Hypotheses
The following four different levels of hypotheses are encountered in behavioral
research:
Value-laden or Nontestable Hypotheses: Predictions minimize error in
the research process while biases become embedded within the
predictions and increase the error.
Ex: We will show that compensation rewards are more effective than
praise rewards as an incentive for housekeeping employees.
-
Implied Hypotheses: Frequently, when a hypothesis is not implicitly
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stated, we can infer one based on the tone of the Introduction. The
Introduction may included references to the idea that certain technique
or procedure may be more effective than others, but the hypothesis is
not directly stated.
In the article “ Self-actualization in Marital Enrichment”, based on the tone of
the Introduction, in the absence of an explicit hypothesis what hypothesis
can be inferred?
Ex: PEP will result in significant increases on twelve subscale
measures of self-actualization as compared to no PEP.
Partial and Complete Criteria Hypotheses
Consider:
Group study contributes to better achievement.
This directional hypothesis is brief, but it is not clear. Two general variables are
stated (type of study and achievement) but there is no comparison with group
study. Further specificity such as the type of achievement would increase clarity.
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The hypothesis seems testable and we can analyze whether a strong rationale
has been proven by the review of the literature.
Group study increases GPA when compared to self-study.
The reworded hypothesis better meets the first three criteria and we can now
determine if a rationale has been provided. We can also analyze whether the
variables are consistent with the Statement of Purpose and the variables
operationalized in the Instrumentation subsection.
Evaluating Hypotheses
The relationship among variables conceptualized in the Statement of
Purpose and Hypotheses with those operationalized in the Instrumentation
subsection is an important way by which the researcher can weave and
interrelate the various components of the research process into a coherent and
integrated entity.
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