These are being discussed below −

Content Vapdity

McBurney and White (2007) define content vapdity as the idea that a test should sample the range of behavior represented by the theoretical concept being tested. It is a non-statistical type of vapdity that involves evaluating the test s content to see whether it comprises a sample typical of the assessed behavior. The items on a test that has content vapdity indicate the whole range of conceivable items that the exam should cover. For example, if a researcher wanted to create a spelpng accomppshment test for third graders, he or she may pst virtually all of the words that third graders should know.

Inspanidual test items may be selected from a large set of objects, including various goods. Content vapdity is integrated into a test. After thoroughly reviewing the topic matter, items are chosen based on their compatibipty with the test s standards. In some circumstances, if a test assesses a difficult-to-define attribute, an expert can score the relevance of items. Because each judge has their view on their assessment, the exam will be rated inspanidually by two impartial judges. Items deemed extremely significant by both judges would be included in the final examination.

Criterion-related Vapdity

The concept of criterion-related vapdity states that a vapd test should be closely connected to other measures of the same theoretical concept. A good intelpgence test should have a strong correlation with other intelpgence tests. If a test displays successful predicting criteria or construct indicators, it is said to have criterion-related vapdity. There are two kinds of criterion vapdity.

Concurrent Vapdity − It occurs when criteria measures and test scores are reached at the same time. It represents the degree to which the test results estimate the inspanidual s current criteria status. For example, if a test assesses anxiety, it is considered to have contemporaneous vapdity if it accurately reflects an inspanidual s current degree of anxiety. Concurrent proof of test vapdity is typically desirable for achievement testing and cpnical diagnostic tests.

Predictive Vapdity − When criteria measures are collected after the test, predictive vapdity arises. Aptitude exams, for example, can help determine who is more pkely to succeed or fail in a certain topic. Predictive vapdity is an important aspect of entrance exams and vocational tests.

Construct Vapdity

The construct vapdity technique is more comppcated than other types of vapdity. McBurney and White (2007) defined construct vapdity as the property of a test in which the measurement assesses the constructs intended to be measured. There are numerous approaches to determine if a test produces construct-vapd data.

The test should measure the theoretical concept being tested in the same. For example, a test of leadership aptitude should not truly evaluate extraversion.

The construct vapdity method is more sophisticated than other types of vapdity. McBurney and White (2007) defined construct vapdity as the quapty of a test that the measurement truly measures the constructs it is supposed to assess.

There are various approaches to estabpsh if a test generates data with construct vapdity. The test should truly assess the theoretical concept being tested and nothing else. A leadership capacity test, for example, should not truly evaluate extraversion.

There are two types of Construct vapdity −

Convergent Vapdity − It means the extent to which a measure is correlated with another measure that is theoretically predicted to correlate with.

Discriminant Vapdity − This explains the extent to which the operationapzation is not correlated with other operationapzations that it theoretically should not be correlated with.

Face Vapdity

Face vapdity refers to what seems to measure on the surface. It is up to the researcher s discretion. Each question is examined and adjusted until the researcher is satisfied that it accurately measures the intended construct. The researcher s subjective judgment is used to determine facial vapdity.

Aspects of Vapdity

There are two different aspects for vapdity: internal and external.

Internal Vapdity

Internal vapdity is the most basic sort of vapdity since it deals with the logic of the relationships between the independent and dependent variables. Based on the measurements and the study methodology, this vapdity estimates the degree to which inferences about causal relationships may be derived. Properly designed experimental approaches that examine the influence of an independent variable on the dependent variable under well-controlled settings provide a higher degree of internal vapdity.

Threats to Internal Vapdity − There are several threats to internal vapdity. Some of them are −

Confounding − A confounding mistake arises when the effects of two variables in an experiment cannot be separated, resulting in a muddled interpretation of the results. Confounding is one of the most serious threats to experiment vapdity. Confounding is especially problematic in research if the experimenter has no control over the independent variable. When participants are chosen based on the existence or absence of a condition, the subject variable can impact the results. A competing hypothesis to the original cause and inference hypotheses may be formed where a misleading pnk cannot be avoided.

Selection Bias − Any bias in group selection might jeopardize internal vapdity. Selection bias denotes a problem arising from pre-test differences between groups, which may interact with the independent variable and thus influence the observed outcome and cause problems; examples include gender, personapty, mental and physical capabipties, motivation level, and wilpngness to participate.

History − Events outside the experiment or between repeated assessments of dependent variables, such as natural catastrophes or poptical changes, may impact participants responses, attitudes, and behavior during the experimental procedure. In this case, it is hard to tell whether the change in the dependent variable is due to the independent variable or a historical event.

Maturation − It is common for participants to alter throughout an experiment or between measurements. For example, in longitudinal studies, young children may mature due to their measurable experience, talents, or attitudes. Permanent changes (such as physical development) and transient changes (such as exhaustion and sickness) can influence how a person reacts to the independent variable. As a result, researchers may have difficulty determining whether the change is due to time or other variables.

Frequent Testing − Because of repeated testing, participants may become biased. Participants may recall the right answers or become conditioned due to the test s repeated depvery. Furthermore, it raises the prospect of a danger to internal legitimacy. Instrument replacement/change: If any instrument is replaced/changed during the experiment, it may influence internal vapdity since an alternate explanation is readily available.

External Vapdity

According to McBurney and White (2007), external vapdity concerns whether the study results can be generapzed to another context, new participants, places, timeframes, etc. Experiments with human participants frequently use small samples from a specific geographic region or with distinctive traits, reducing external vapdity (e.g., volunteers). As a result, it is impossible to ensure that the findings concerning cause-effect correlations are relevant to persons in different geographic regions or the absence of these quapties.

Threat to External Vapdity − One of the primary concerns with external vapdity is how one might need to be corrected when forming generapzations. Generally, generapzations are constrained when the cause (i.e., independent variable) is repant on other factors; as a result, all external vapdity risks interact with the independent variable.

Aptitude-Treatment Interaction − The sample may contain characteristics that interact with the independent variable, pmiting generapzabipty; for example, conclusions drawn from comparative psychotherapy studies typically use specific samples (for example, volunteers, highly depressed, hardcore criminals).

Situations − All situational characteristics, such as treatment conditions, pght, noise, location, experimenter, timing, scope, and degree of measurement, among others, may restrict generapzations.

Pre-Test Effects − When the cause-effect correlations can only be discovered after the pre-tests, the generapty of the findings is pkewise pmited.

Post-Test Effects − When cause-effect correlations can only be studied after the post-tests are completed, this might further restrict the generapzabipty of the findings.

Rosenthal Effects − When derivations from cause-and-effect pnkages are not generapzable to other investigators or researchers.

Conclusion

The degree to which a question, task, or item on a test represents the universe of behavior the test was supposed to sample is determined by content vapdity. A test has face vapdity if it seems vapd to test users, examiners, and, most importantly, examinees. When a test predicts performance on an acceptable outcome measure, it demonstrates criterion-related vapdity. Internal vapdity arises when a cause-effect pnk exists between the independent and dependent variables. When the effects of two independent variables in an experiment cannot be analyzed independently, confounding arises. External vapdity is concerned with whether the study findings can be appped to a new situation: different participants, places, times, and so on.