A good score on the ASVAB is different than a minimum required score.  Each of the military branches will have their own minimum required scores (see below).  In practice, however, each branch will be more selective in their recruiting.  A score of 50 on the ASVAB implies that you scored as well or better than 50% of comparable test-takers.  Since ASVAB scores are used for many purposes (e.g., enlistment eligibility, military job placements, and career exploration), it is important that you score well on the ASVAB.  A score of 60 or better should be your minimum target.
The projected active duty end strength in the armed forces for fiscal year 2017 was 1,281,900 servicemembers,[6] with an additional 801,200 people in the seven reserve components.[6] It is an all-volunteer military, but conscription through the Selective Service System can be enacted at the President's request and Congress' approval. All males ages 18 through 25 who are living in the United States are required to register with the Selective Service for a potential future draft.
Jobs in the Marine Corps are referred to as”MOS” (short for Military Occupational Specialty). To find the MOSes you qualify for, the Marine Corps organizes your ASVAB subtest scores into various groups known as line scores. The ASVAB subtests are: General Science (GS); Arithmetic Reasoning (AR); Word Knowledge (WK); Paragraph Comprehension (PC); Numerical Operations (NO); Coding Speed (CS); Auto and Shop Information (AS); Mathematics Knowledge (MK); Mechanical Comprehension (MC); Electronics Information (EI); and Sum of Word Knowledge and Paragraph Comprehension (VE). It’s important to remember that as Numerical Operations (NO) and Coding Speed (CS) subtests are phased out, some line scores may be updated.
Law prohibits applicants in Category V from enlisting.[6] In addition, there are constraints placed on Category IV recruits; recruits in Category IV must be high school diploma graduates but cannot be denied enlistment solely on this criteria if the recruit is needed to satisfy established strength requirements. Furthermore, the law constrains the percentage of accessions who can fall between Categories IV-V (currently, the limit is 20% of all persons originally enlisted in a given armed force in a given fiscal year).[6]

Once you have learned about yourself, you are ready to begin exploring different career options.  Chances for a rewarding career are improved if you select a career field that matches your interests, values, skills, and abilities.  While learning about various careers, you should be constantly asking yourself, “How well does this career match my current interests, values, and abilities?” and “Will this career lead to a lifestyle I want?”
Word Knowledge (WK), Paragraph Comprehension (PC), Mathematics Knowledge (MK), Electronics Information (EI), Auto & Shop Information (AS), and Mechanical Comprehension (MC). These subtests focus on basic knowledge of science, math, writing and vocabulary, an understanding of structural development and mechanics, auto function and repair, and a knowledge of electric currents, electronic systems, and circuits. These are all skills and knowledge that are necessary for different sectors of military service. Scores in each subtest are based on the student’s ability to answer the questions correctly and to complete the test in time to answer as many of the questions as possible.
An important part of the military intelligence role is the military analysis performed to assess military capability of potential future aggressors, and provide combat modelling that helps to understand factors on which comparison of forces can be made. This helps to quantify and qualify such statements as: "China and India maintain the largest armed forces in the World" or that "the U.S. Military is considered to be the world's strongest".[29]
The four most important sections of the test—Word Knowledge, Paragraph Comprehension, Arithmetic Reasoning, and Mathematics Knowledge-make up your Armed Forces Qualifications Test (AFQT) score. Your AFQT score ranges from 0 to 100 and determines if you are able to enlist in the military and which jobs and programs you may qualify for when you are in.
Word Knowledge (WK), Paragraph Comprehension (PC), Arithmetic Reasoning (AR), and Mathematics Knowledge (MK). Scores on the AFQT are used to determine your eligibility for enlistment in the Army, Navy, Air Force, or Marine Corps. The other six test scores on the ASVAB tests are used to determine the best job for you in the military as your grades will demonstrate knowledge, skill, and interest in certain subjects and tasks. 
There are 65 MEP joint services locations across all 52 states and in Puerto Rico. If you do not live close enough to a MEP, your recruiter will advise you to take the test at one of the MET sites which are located in many Federal government buildings, armories and Reserve stations. With multiple locations across the country to choose from, you won’t have to travel far to take this all-important first step toward a military career.
The underlying model used for the ASVAB is a three-parameter logistic (3PL) model. This model represents the probability that an examinee at a given level of ability will respond correctly to an individual item with given characteristics. The characteristics used are difficulty, discrimination and guessing (this refers to the likelihood that a very low ability examinee would respond correctly simply by guessing).
Capability development, which is often referred to as the military 'strength', is arguably one of the most complex activities known to humanity; because it requires determining: strategic, operational, and tactical capability requirements to counter the identified threats; strategic, operational, and tactical doctrines by which the acquired capabilities will be used; identifying concepts, methods, and systems involved in executing the doctrines; creating design specifications for the manufacturers who would produce these in adequate quantity and quality for their use in combat; purchase the concepts, methods, and systems; create a forces structure that would use the concepts, methods, and systems most effectively and efficiently; integrate these concepts, methods, and systems into the force structure by providing military education, training, and practice that preferably resembles combat environment of intended use; create military logistics systems to allow continued and uninterrupted performance of military organisations under combat conditions, including provision of health services to the personnel, and maintenance for the equipment; the services to assist recovery of wounded personnel, and repair of damaged equipment; and finally, post-conflict demobilisation, and disposal of war stocks surplus to peacetime requirements.
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