Effective selection is therefore important and depends, to large degree on the basic testing concepts of validity and reliability.
I .validity
A test is a sample of a person’s behavior, but some tests are more clearly representative of the behavior being sampled that others. A typing test for example, clearly corresponds to an on-thejob behavior. At the other extreme, there may be no apparent relationship between the items on the test and the behavior. This is the case with projective tests.
Test validity
The accuracy with which a test, interview and so on measures what it purports to measure or fulfills the function it was designed to fill. It answers the question, “does this test measure what it’s supposed to measure?” with respect to employee selection tests, validity often refers to evidence that the test is job related- in other words, that performance on the test is a valid predictor of subsequent performance on their job. A selection test must be valid since, without proof of validity, there is no logical or legally permissible reason to continue using it to screen job applicants. In employment testing, there are two main ways to demonstrate a test’s validity:
criterion validity and content validity.
1. Criterion validity
Demonstrating criterion validity means that those who do well on the test also do well on the job and that those who do poorly on the test do poorly on the job, thus the test has validity to extent that the people with higher test scores perform better on the job. In psychological measurement, predictor is the measurement (in this case, the test score) that you are trying to relate to a criterion, like performance on the job. The term criterion validity reflects that terminology.
2. Content validity
A test that contains a fair sample of the tasks and skills actually needed for the job in question. Employers demonstrate the content validity of a test by showing that the test constitutes a fair sample of the content of the job. The basic procedure here is to identify job tasks and behaviors that are critical to performance and then randomly detect a sample of those tasks and behaviors to be tested.
Demonstrating content validity sounds easier than it is in practice. Demonstrating that;
- The tasks the person performs on the test are really a comprehensive and random sample of the tasks performed on the job.
- The conditions under which the person takes the test resemble the work situation, is not always easy.
For many jobs, employers must demonstrate other evidence of a test’s validity- such as its criterion validity.
Reliability
Is a test’s second important characteristic and refers to its consistency. It is “the consistency of scores obtained by the same person when retested with the identical tests or with an equivalent form of a test.” A test’s reliability is very important; if a person scored 90 on an intelligence test on Monday and 130 when retested on Tuesday, you probably wouldn’t have much faith in the test.
There are several ways to estimate consistency or reliability. You could administer the same test to the same people at two different points in time, comparing their test scores at time 2 with their scores at time 1; this would be a retest estimate. Or you could administer a test and then administer what experts believe to be an equivalent test later; this would be an equivalent form estimate.
A test’s internal consistency is another measure of its reliability. For example, suppose you have 10 items on a test of vocational interest; you believe this measure in various ways, the person’s interest in working outdoors. You administer the test and then statistically analyze the degree to which responses to these 10 items vary together. This would provide a measure of the internal
consistency is one reason you find apparently repetitive questions on some test questionnaires. A number of things could cause a test to be unreliable. For example the questions may do a poor job of sampling the material; or there might be errors due to changes in the testing conditions
Interviewing Candidates
An interview is a procedure designed to solicit information from a person’s oral responses to oral inquiries; a selection interview, is a selection procedure designed to predict the future job performance on the basis of applicants oral responses to oral inquiries. Interview is by far the most widely used personnel selection procedure
Types of Interviews
Interviews can be classified in four ways according to;
1. Degree of structure
2. Purpose
3. Content
4. The way the interview is administered
Inn turn the seven main types of interviews used at work- structured, non-structured, situational, sequential, panel, stress and appraisal can each be classified in one or more of these four ways.
I. The structure of the interview
Interviews can be classified according to the degree to which they are structured. In an unstructured or nondirective type of interview you ask questions as they come to mind the interviewer pursues points of interest as they come up in response to questions. There is
generally no set format to follow and the interview can take various directions. While questions can be specified in advance, they usually are not and there is seldom a formalized guide for scoring the quality each answer. Interviewees for the same job thus may or may not be asked the same or similar questions based on the candidate’s last statement and to pursue points of interest
as they develop.
The interview can also be structured. In the classical structured interview, the questions and acceptable responses are specified in advance and the responses are rated for appropriateness of content. It is an interview following a set sequence of questions. In practice, however not all structured interviews go so as to specify acceptable answers. Structured and no structured interviews each have their pros and cons. With structured interviews all applicants are generally asked all questions by all interviewers that meet and structured interviews are generally more valid. Structured interviews can also help interviewers who may be less comfortable interviewing to ask questions and conduct useful interviews. On the hand, structured interviews don’t always leave the flexibility to pursue points of interest as they develop.
The Purpose of the Interview
Employee- related interviews can also be classified according to their purpose. Thus as noted earlier, a selection interview is a type of interview designed to predict future job performance on the basis of applicants oral responses to oral inquiries. A stress interview is a special type of selection interview in which the applicant is made uncomfortable by a series of sometimes-rude. The aim of the stress interview is supposedly to help identify sensitive applicants and those with low or high stress tolerance.
In the typical stress interview, the applicant is made uncomfortable by being put on the defensive by a series of frank and often-discourteous questions from the interviewer. The interviewer might first probe for weaknesses in the applicant’s background, such as job that the applicant left under questionable circumstances. Having identified these, the interviewer can yet focus on them
hoping to get the candidate to lose his or her composure. Thus a candidate for customer relations’ manager who obligingly mentions having had four jobs in the pat two years might be told that frequent irresponsible and immature behavior. If the applicant then responds with a reasonable explanation of why the job changes were necessary, another topic might be pursued.
On the other hand, if the formerly tranquil applicant reacts explosively with anger and disbelief, this might be taken as a symptom of low tolerance for stress The stress approach can be a good way to identify hypersensitive applicants who might be expected to overreact to mild criticism with anger and abuse. On the other hand, the stress interview’s invasive and ethically questionable nature demands that the interviewers be skilled on the requirements for the job. This is definitely not an approach for amateur interrogations or for those without skill to keep the interview under control.
Interviews serve two more purposes in the employment context. An appraisal interview is a discussions following a performance appraisal in which supervisor and employee discuss the employee’s rating and possible remedial actions. When an employee leaves a firm for any reason, exit interview is often conducted. An exit interview usually conducted by the HR department, aims at eliciting information about the job or related matters that might give the employer a better insight into what is right or wrong about the company.
The content of the interview
Interviews can also be classified according to the content of their questions. A situational type of interview is one in which the questions focus on the individual’s ability to project what his or her behavior would be a given situation. For example, a candidate for a
supervisor’s position may be how asked how he or she would respond to a subordinate coming to work late three days in a row. The interview can be both structured and situational with predetermined questions requiring the candidate to project what his or her behavior would be: in a structured situational interview the applicant could be evaluated, say on his or her choice between letting the subordinate off with a warming versus suspending the subordinate for one week.
Job-related interviews are those in which the interviewer attempts to asses the applicant’s past behaviors for job-related information, but most questions are not considered situational. In other words questions don’t revolve around hypothetical situations or scenarios. Instead supposedly job-related questions (such as „which courses did you like best in business school?“) are asked in order to draw conclusions about say, the candidate’s ability to handle the financial aspects of the job to be filled.
The behavioral interview is gaining in popularity. In a behavioral interview a situation is described and interviews are asked how they have behaved in the past in such a situation. Thus while situational interviews ask interviewees to describe how they would react to a situation today or tomorrow, the behavioral interview asks interviewees to describe how they did react to situations in the past.
Finally, psychological interviews are interviews conducted by a psychological in which questionaire panel s are intended to assess personal traits such as dependant habit. The interview may use situational job-related or behavioral questions and be either structured or unstructured.
Psychological interviews generally have a significantly unstructured element.
Administering the interview
interviews can also be classified based on how they are administered: one-on-one or by a panel of interviewers; sequentially or all at once; and computerized or personally. For example, most interviews are adiministered one-on-one. As the name implies, two people meet alone and one interviews the other by seeking oral responses to oral inquiries. Most selection processes are sequential. In a sequence interview the applicant is interviewed by several persons in sequence before a selection decision is made. In an unstructured sequence interviewer may look at the applicant from his or her on point of view, ask different questions and form an independent opinion of the candidate on the other hand, in s structured sequential or serialized interview each interviewer rates the candidate on a standard evaluation form and the ratings are compared before the hiring decision is made.
The panel interview means the candidate is interviewed simultaneously by a group (or panel) of interviewers (rather than sequentially). The group structure has several advantages. A sequential interview often has candidates cover basically the same ground over and over again with each interviewer. The panel interview, on the other hand, allows each interviewer to pick up on the candidate’s answers, much as reporters do in press conferences than are normally produced by a series of one-on-one interviews. On the other hand, some candidates find panel interviews more stressful and they may actually inhibit responses. An even more stressful variant is the mass interview.
Increasingly, interviews aren’t administered by people at all but are computerized. A computerized selection interview is one in which a job candidate’s oral and/or computerized responses are obtained in response to computerized oral, visual or written questions and/or situations. The basic idea is generally to present the applicant with a series of questions regarding his or her background, experience education, skills, knowledge and work attitudes specific questions that relate to the job for which the person has applied. In a typical computerized interview the questions are presented in multi-choice format, one at a time and the applicant is expected to respond to the questions on the computer screen by pressing a key corresponding to his or her desired response. For example a sample interview question for a person applying for a job as a store clerk might be:
How would your supervisor rate your customer service skills?
- Outstanding
- Above average
- Average
- Below average
- Poor
Questions on a computerized interview like this come in rapid sequence and require concentration on the applicant’s part. The typical computerized interview then measures the response time to each question. A delay in answering certain such as “can you be trusted?“ can flag a potential problem.
Computer-aided interviews are generally used to reject totally unacceptable candidates and to select those who will move on to a face-to-face interview. Computer-aided interviews can be very advantageous. Systems like those on-line substantially reduce the amount of time managers devote to interviewing what often turn out to be unacceptable candidates. Applicants are reportedly more honest with computers than they would be with people, presumably because computers are not judgemental. The computer can also be sneaky: if an applicant takes longer than average to answer a question like, ‘Have you ever been caught stealing?“ he or she may be summarily screened out or at least questioned more deeply in that area by a human interviewer. On the other hand, mechanical nature of computer-aided interviews can leave applicants with the impression that the prospective employer is rather impersonal.
How useful are interviews?
The ironic about interviews is that while they’re used by virtually all employers, the statistical evidence regarding the validity is actually very mixed. Much of the earlier research gave selection interviews low marks in terms of reliability and validity. However recent studies indicate that key to an interview’s usefulness is the manner in which it is administered.
Specifically, the following conclusions are warranted based on one recent study of interview validity:
With respect to predicting job performance, situational interviews yield a higher mean validity than do job-related (or behavioral) interviews, which in turn yield a higher mean Validity than do psychological interviews. Structured interviews, regardless of content
are more valid than unstructured interviews are more valid than are panel interviews, in which multiple interviewers provide ratings in one setting.
In summary, structured situational interviews conducted one-to-one individually seem to be the most useful for predicting job performance. Unstructured interview in general, psychological interviews and panel interviews are some what less useful for predicting job performance.
Interviewing and the law: employment Discrimination “ Testers“
an interview is a selection procedure; interviewers must therefore avoid asking questions concerning, for instance, candidates marital status, childcare arrangements, ethnic background and worker’s compensation history. The increasing use of unemployment discrimination testers has made such care even more important. Testers are individuals who apply for employment, which they do not intend to accept for the sole purpose of uncovering unlawful discriminatory hiring practices.
