Socrates once said, "The unexamined life is not worth living." Yet sometimes it seems that Americans are obsessed with self-examination and constant change. Individuals once spent an entire lifetime with a single employer, but most people today evaluate their career and lifelong goals every few years. It's common to leapfrog from opportunity to opportunity and to re-make a professional identity several times over.If you're entering college and are perplexed about your future goals, join the club. Even as graduates enter the workplace, they continue to assess their skills and dreams to find lasting success and happiness.Psychologists, educators, and employers have developed a battery of tests that measure your likes and dislikes, your aspirations and aptitudes. A dizzying range of online personality and career assessment tests are free for the taking to help you discover your heart's desire or make mid-life course corrections.Some help you find out whether you'd rather pick flowers in Holland in the summer or drive an 18-wheel truck in blizzard conditions along the Al-Can highway. Employers administer assessments to see how well you'll do in a team environment, if you can take direction, supervise others, or prefer to sit alone in a cubicle listing to your iPod.You'll find dozens--if not hundreds--of online career and personality tests. Many are free, while some companies charge money. Most offer a free topside overview, with more complex analyses available for a price. Beware, however, for aptitude assessment tests are not always as advertised.Measuring the Tests that Measure YouNo one likes being lumped into a career or personality group. In America, especially, we're individuals to the very end. It helps to think of online test results as an effort to spot your tendencies, rather than making your choices for you. Above all else, you'll want to focus your time on tests that rely on time-tested psychological models to drive the assessment. Examine the Web sites you visit for information on the methodology--and eschew tests that are glib, bizarre, or downright flakey.Let's look at four standardized aptitude and profile assessments used by professionals.Myers Briggs Personality Test (MBPT)The granddaddy of most personality and job assessments, the MBPT is most likely the model behind the tests you'll discover at online evaluation sites. You'll be categorized onto one of 16 personality types, based on your responses to questions that evaluate how you deal with life (extroversion vs. introversion), how you process information (sensing vs. intuition), how you make decisions (thinking vs. feeling), and how you organize your life (judging vs. perception).The Six Factor Personality Questionnaire (SFPQ)The SFPQ is a well-respected assessment - online myers briggs assessment - tool that measures six personality factors, with each factor broken into categories that are calculated by 108 Likert questions. Likert questions ask you to identify with a given statement using the following scale--Strongly disagree, Disagree, Neither agree nor disagree, Agree, or Strongly agree.SFPQ personality factors include Agreeableness, Extraversion, Independence, Openness to Experience, Methodicalness, and Industriousness. A SFPQ test can help you understand your traits with respect to temperament, autonomy, endurance, achievement, logic, and resistance to or acceptance of change.The Hogan Personality Inventory (HPI)Tests based on the HPI model measure your personality, your traits in respect to on-the-job performance, and your attitude. HPI tests fall into one or more of the following assessment categories--the Hogan Development Survey, Motivation, Values, and Preferences Inventory, and Hogan Personality Inventory.HPI questions produce personality trait identifiers and motive qualities that can include colorful, dutiful, bold, imaginative, altruistic, power, security, cautious, and excitable. Occupational aptitude measurements rank you in categories that include integrity, leadership ability, initiative, decision-making skills, communication skills, self-esteem, curiosity, sense of responsibility, and creative potential.Guilford-Zimmerman Temperament Survey (GZTS)The GZTS is strictly a personality evaluator, used to measure learning potential, possible learning disabilities, personality, and temperament as it applies to the workplace, conflict, and personal relationship skills. Scales measure quantifiable responses to qualities of restraint, emotional stability, objectivity, friendliness, and thoughtfulness.16 Personality Factors (16PF)The 16PF text was created by psychologist Raymond Cattell to measure so-called primary factors that show your tendencies in major assessment categories of warmth, reasoning, emotional stability, dominance, liveliness, rule-consciousness, social boldness, sensitivity, vigilance, abstractedness, privateness, apprehension, openness to change, self-reliance, perfectionism, and tension.Beyond the Personality Testing NumbersYou'll no doubt discover a broad range of online career tests that are based on these highly regarded methodologies. While the governing categories may not be immediately visible, they are there. Instead of dry category breakdowns, you're more likely to see questions based on the SFPQ model. You'll be given a direct statement and asked to rank your identification with it. Sample questions/declarations might include:I love to work alone.I have difficulty reaching decisions.I prefer not to always show how I feel.I'd rather be a farmer than a stockbroker.Your responses to these statements translate into raw numbers that fit the 16PF or SFPQ qualities.If you're taking a personality or career assessment test online, it's vital to consider the results as sweeping generalizations about your career or life-goal tendencies that give you guidance but not clear-cut directions. Think of suggested career choices as options, and then see how you respond emotionally to detailed career descriptions you find elsewhere in your search.As a bonus, a test may reveal broader career fields than you imagined for yourself as well as greater self-wisdom about your likes, dislikes, aptitudes, and skills. Remain open to suggested fields. If a test sends you into unexplored territory and you respond with energy and delight, you may have hit the jackpot.Caveat emptor--buyer beware. Online career testing is at best uneven and, at worst, misleading marketing junk to promote a paid survey. Don't take yourself--or the results--too seriously. Before entering personal information other than your email address on an exam site, look for privacy declarations or contact the Webmaster. Before you ante up for extras or detailed analyses, look at the quality and sensibility of your free results.