Statıstıcs I Ara 7. Deneme Sınavı

The median is the middle value of an ordered dataset. The correct answer is A.

Your Anatolian University student number is data, not variable. pg. 14. Correct answer is C.

No, it is data. pg. 14. Correct answer is D.

35 : median = (14 + 1) / 2 = 7.5 th observation ; then average of 7th and 8th observations : (35 + 35) / 2 = 35

Histogram is a graph that is very similar to a bar chart except that bar charts are drawn for qualitative data but histograms are drawn for continuous data. Histograms will help us to identify the center, shape and symmetry of the data. A histogram can tell us about the peaks and extreme values, whether the distribution of data is skewed to the left, skewed to the right, bell-shaped, uniform or bimodal. A histogram can also be used to check out the normality.

The most repeated value is 4, therefore the mode is 4.

Categorical variables and data can be either nominal or ordinal. Examples of nominal categorical variables are gender, region of residence, field of study, type of transport, type of housing, etc. There i­s no orderi­ng i­n the categori­es of these variables. . Exam grade is an ordinal categorical variable, since its categories are ordered: A is better than a B, B is better than a C, and so on. Other examples of ordinal categorical variables are ­income group (I­f i­ncomes have been categorized), an attitude question in a survey where possible responses are strongly agree/agree/disagree/strongly disagree (these categories have an order).

A data set is a collection of facts aggregated for a specific purpose. Elements are the entities on which the data are collected. In the table, an element of the data set i­s a particular patient. A variable i­s a characteristic of interest about an element. Thi­s characteristic takes on d­ifferent values for d­ifferent elements. The Gender and the name in the table are a qualitative variable because their outcomes are nonnumeric. Of the four variables in the data set in table, two are qualitative (Name and Gender) and two are quantitative (Age and Weight). The outcomes obtained on all variables for one element i­n the data set is called a case.

Interpretation of the frequency distribution table can be easier or clearer when we use the percentage of the frequency. Percentage representation of frequency can also be displayed in the frequency distribution table. Percentage of frequency is called the relative frequency and the table is called relative frequency distribution table. Relative frequency can be used for both quantitative and qualitative variables. The relative frequency for a class is calculated as follows: Relative Frequency = fi/ n where, fi is the frequency for class i and n is the sample size. In this case, fi is 21and n is 85. The percentage of relative frequency is 24,7.

Because the difference in the counts of words could be stated in percentages, it is a ratio type of measurement.

57 : median = (16 + 1) / 2 = 8.5 th observation ; then average of 8th and 9th observations : (48 + 66) / 2 = 57. pg. 81. Correct answer is E.

Class Width=Range/Number of classes

where Number of Classes=?n, where n=number of observations

Thus Number of Classes=?500=22.36

But when the number of classes is larger than 20 we take it as 20. So in this case:

Class Width=(40-20)/20=20/20=1kg

A pie chart is usually used for categorical data. In pie chart components or outcomes of a total frequency is shown as sectors of a circle. The shape resembles to a pie, hence the name of the chart. In pie chart, the categories are divided in to slices/sectors. Each slices’ size is proportional to the total number of objects.

Histogram is a graph that is very similar to a bar chart except that bar charts are drawn for qualitative data but histograms are drawn for continuous data. In order to draw the histogram of the data, we usually need to have a large sample. If you remember from previous chapters, the data was classified in to grouped frequency distributions, basically you can think histograms as bar plots of grouped frequency distributions. If you create a grouped frequency distribution of the data, you can easily create the histogram of the same data. Similarly, by looking at a histogram one may easily create the grouped frequency distribution of the data. In bar charts the columns/bars are separated from each other by a convenient distance whereas in histogram the columns/bars are adjacent to each other.

Age is an interval-scale variable: to compare two children of ages 10 and 12, we would compute the interval difference, i.e. 2 years. We would not say the 12-year old is 20% older than the 10-year old.

In this table, there are two categorical variables. One is the variable gender which has two categories, female and male. The other categorical variable is the variable excel knowledge which has two categories, yes and no. Thus, there are two categorical variables.

Ifa data set includes two different categorical variables, we use a two-way table (contingency table) todemonstrate the relationship and interaction of the two categorical variables. A two-way table of counts  organizes data about two categorical variables measured from the same set of individuals. A contingency table is a special type of frequency distribution table, where two variables are shown simultaneously and
it is used to determine if one categorical variable is related to another categorical variable. 

Eskişehir's beach's users is variable, not data. pg. 14. Correct answer is D.

When we create the contingency table with row and column percentages, within the people who do not have technical knowledge (No) the percentage of male and female are 50% and 50%, respectively.

26 : occurs most often, it is repeated 4 times