MMW Midterm pt. 2

SAMPLE

is a portion/part or subgroup of the population/universe

RANDOM SAMPLING

is the most commonly used sampling technique in which each member of the population is given an equal chance of being selected in the sample.

EQUIPROBABILITY

means that each member of the population has an equal chance of being selected and included in the sample.

INDEPENDENCE

means that the chance of one member of being drawn does not affect the chance of the other member

RESTRICTED RANDOM SAMPLING

involves certain restrictions intended to improve the validity of the sample- this design is applicable only when the population being investigated requires homogeneity.

UNRESTRICTED RANDOM SAMPLING

is considered the best random sampling design because there were no restrictions imposed and every member in the population has an equal chance of being included in the sample.

LOTTERY OR FISHBALL SAMPLING

This is done by simply writing the names or numbers of all the members of the population in small rolled pieces of paper which are later placed in a container. The researcher shakes the container thoroughly then draws “n” out of “N” pieces of papers as desired for a sample. This is usually done in a lottery.

SAMPLING WITH THE USE OF TABLE OF RANDOM NUMBERS

If the population is large, a more practical procedure is the use of this which contains rows and columns of digits randomly ordered by a computer. A sample of size “n” can be generated by beginning at an arbitrary point in it, closing your eyes and haphazardly pointing at an entry in the Table. Then they proceed in any direction, vertically, horizontally, or diagonally until “n” distinct numbers could represent the numerically coded elements in the population.

SYSTEMATIC SAMPLING

It is done by taking every kth element in the population. It implies a group of individuals arranged in a waiting line or in a methodical manner. For instance, the objective is to get the opinion of employees regarding employee-management relations, a sample of size “n” will be selected from the list of employees arranged alphabetically or according to age, experience, position or academic rank. By systematic sampling, every kth employee from the listed order will be included in a sample. if “N” is known, k value can be calculated as k =N/n size where N is the population n is the sample size

STRATIFIED RANDOM SAMPLING

This is when the population can be partitioned into several strata or subgroups, it may be wiser to employ the stratified technique to ensure a representative of each group in the sample Random samples will be selected from each stratum. Selecting a sample with this technique is quite difficult and costly since it requires a complete listing, called frame, of all elements in the population.

SIMPLE STRATIFIED RANDOM SAMPLING

When the population is grouped into more or less homogeneous classes, that is, different groups but with relatively common characteristics, then each can be sampled independently by taking an equal number of elements from each stratum.

STRATIFIED PROPORTIONAL RANDOM SAMPLING

In some cases, the characteristic of the population is such that the proportions of the subgroups are grossly equal. The researcher may wish to maintain these characteristics in the sample with the use of the stratified proportion technique.

MULTI STAGE OR MULTIPLE SAMPLING

This technique uses several stages or phases in getting samples from the population. However, selection of the sample is still done at random. This method is an extension or a multiple of the stratified random sampling technique. The number of stages depends on the number of the population and the sample size needed in the survey.

JUDGEMENT OR PURPOSIVE SAMPLING

non-random or non-probability sampling that plays a major role in the selection of a particular item and/or in making decisions in cases of incomplete responses or observation. This is usually based on a criteria laid down by the researcher or his adviser.

QUOTA SAMPLING

This is a relatively quick and inexpensive method to operate since the choice of the number of persons or elements to be included in a sample is done at the researcher's own convenience or preference and is not preference and is not predetermined by some carefully operated randomizing plan.

CLUSTER SAMPLING

Sometimes referred to as an area sampling because it is usually applied on a geographical basis. The population is grouped into clusters or small units, e.g., blocks or districts, in a city or municipality. Area sampling usually requires larger elementary units than those required in simple random sampling. It is not a common practice, however, that every individual located in a selected area is interviewed. Often additional sampling stages are introduced.

INCIDENTAL SAMPLING

This design is applied to those samples which are taken because they are the most available. In an interview, for instance, an interviewer can simply choose to ask those people around him or in a coffee shop where he is taking a break.

CONVENIENCE SAMPLING

This method has been widely used in televisions and radio programs to find out opinions of TV viewers and listeners regarding controversial issues. While the issue is being discussed in a talk show, the hosts will immediately get responses and comments from those who will call their telephone operators. This method, of course, is biased against those without telephones in their houses.

PRIMARY SOURCE

which a first-hand information is obtained usually by means of personal interview and actual observation

SECONDARY SOURCE

information is taken from other’s works, new reports, readings, and those that are kept by the National Statistics Office, Securities and Exchange Commissions, SSS, and other government and private agencies.

MANAGEMENT INFORMATION SYSTEM

where all information about their business is made available in order to facilitate verification of claims and to come up with wise management decisions.

DIRECT OR INTERVIEW METHOD

is a person-to-person interaction between an interviewer and interviewee. Tape recorded or written interviews will help the researcher obtain exact information from the interviewee.

INDIRECT OR QUESTIONNAIRE METHOD

is an alternative method for the interview method. Written responses are obtained by disturbing questionnaires (a list of questions intended to elicit answers to a given problem, must be given in a logical order and not too personal) to the respondents through mail or hand-carry.

REGISTRATION METHOD

is enforced by private organizations or government agencies for recording purposes

OBSERVATION METHOD

Is a scientific method of investigation that makes possible use of all senses to measure or obtain outcomes/responses from the object of study.

EXPERIMENTATION

Is used when the objective is to determine the cause-and-effect of certain phenomena under some controlled conditions.

TEXTUAL PRESENTATION

This form of presentation combines text and numerical facts in a statistical report

TABULAR PRESENTATION 1

This form of presentation is better than textual form because it provides numerical facts in a more concise and systematic manner.

TABULAR PRESENTATION 2

Each class/subclass is assigned to a particular row or column and figures for various classifications are noted in appropriate calls

GRAPHICAL PRESENTATION

This form is the most effective means of organizing and presenting statistical data because the important relationships are brought out more clearly and creatively in virtual solid and colorful figures.

LINE GRAPH

It shows relationships between two sets of quantities. This is done by plotting point of X set of quantities along the horizontal axis against the Y set of quantities along the vertical axis in a Cartesian coordinate plane. Those plotted points will be connected by a line segment which finally forms the line graph. It is often used to predict growth trends for a longer period of time.

BAR GRAPH OR HISTOGRAM

It consists of bars or rectangles of equal widths, either drawn vertically or horizontally, segmented or non-segmented. Is done by drawing rectangles with length proportional to the frequencies of observed items or magnitude of classes under study. Two or more kinds of information can be compared by showing them in multiple bar graphs, each of which is shaded with different colors to give distinctions of each. In some cases, bars can be shown in opposite directions above and below a zero line to illustrate profits/earnings (positive) and loss/deficit relationship.

CIRCLE GRAPH OR PIE CHART

It represents relationships of the different components of a single total as revealed in the sectors of a circle. The angles or size of the sectors should be proportional to the percentage components of the data which give a total of 100%. Colors, legends, and cross hatching will be useful in identifying each components.

PICTURE GRAPH OR PICTOGRAM

It is a visual presentation of statistical quantities by means of drawing pictures or symbols related to the subject under the study. Sizes and magnitudes drawn pictures should be clear enough to depict differences. Legends are sometimes used to represent magnitude of a single unit of the picture then repetitions of this picture are drawn to indicate differences in quantity.

MAP GRAPH OR CARTOGRAM

It is one of the best ways to present geographical data. This kind of graph is always accompanied by a legend which tells us the meaning of the lines, colors or other symbols used and positioned in a map.

SCATTER POINT DIAGRAM

It is a graphical device to show the relationship between two quantitative variables. Unlike the line graph, the plotted points for every pair of X and Y set of quantities are not connected by line segments but are simply scattered on the Cartesian coordinate plane.