Trend Study: A type of longitudinal study in which a given characteristic of some population is monitored over time. Units of Analysis: The what or whom being studied. Results of research are typically graphed as dots, with the mean each sample taken being represented as one dot on the x-axis. A confidence level is the probability that a population parameter is within a certain confidence interval. •the proportion of subjects in the sample : potential subjects in the population. Clitoris, female erogenous organ capable of erection under sexual stimulation. if you studying and you want to know the meaning of word. •Standard error decreases as sample size increases. in a multiple choice test where different questions are worth different numbers of points). The next level of measurement, Interval scales, provide us with still more quantitative information. STEAM Resources, Science Experiments and Projects by PSC. In social science research, the most typical units of analysis are individual people. A confidence interval is the range of values within which a population parameter is estimated to lie. •If one of the parameters is 1.0 or 0.0, the standard deviation will be 0. Usually scales are constructed using the ordinal level of measurement, which organizes items in an order in order to determine degrees of favor or disfavor, but does not provide any meaning of distance between degrees. Poor sampling reduces the validity of using study results to make population inferences. Ecological Fallacy: Erroneously drawing conclusions about individuals solely from the observation of groups. Stratified Sampling: Modification to sampling that involves dividing the population into homogeneous strata before forming samples to increase representativeness within groups. Smith et al. A sample frame is a list of elements composing a population from which a sample is selected (ex. ; earlier "pan of a balance" (late 14c. "to climb by or as by a ladder," late 14c., from scale (n.) "a ladder," from Latin scala "ladder, flight of stairs," from *scansla, from stem of scandere "to climb" (see scan (v.)). They aren't perfect--an aspect or two are inevitably left out. "skin plates on fish or snakes," c. 1300, from Old French escale "cup, scale, shell pod, husk" (12c., Modern French écale) "scale, husk," from Frankish *skala or some other Germanic source, from Proto-Germanic *skælo "split, divide" (source also of Dutch schaal "a scale, husk," Old High German scala "shell," Gothic skalja "tile," Old English scealu "shell, husk"), from PIE root *skel- (1) "to cut.". As research is repeated, means of samples often are duplicated, so their dots are simply placed on top of their duplicates. Pakistan for its electricity needs depends largely on crude oil, but in the last few years, international oil prices are increasing as a result of the ongoing electricity is expensive for Pakistan is very important to find alternative sources of energy. 6-800 cases are usually sufficient no matter size of population. Often, factors such as a researcher's location, ease of access to the population, and personal comfort level towards approaching random strangers, have an influence on bias. It enhances the presentation of whatever variable is being used to divide the groups. Stratified sampling:form of probability sampling where cases are divided into meaningful groups of interest (genders, races, etc) and a random sample is taken from each group. Probability theory uses sample distributions to accomplish this. Permission to Use. •Representativeness: the sample's distribution of characteristics remains true to the population it is sampling, •EPSEM: sampling where every member of a population has an equal chance of selection, •element: any piece of a population--can be a member, a location, or a measurable characteristic, •study population: contains all necessary characteristics for study; sample is selected from here, •random selection: sampling method, every member of a population has an equal chance of selection, •sampling unit: person or group of people considered for selection, •parameter: variable factor within a population, •statistic: a description of a variable within a sample, •sampling error: degree of error expected by not studying an entire population.