Data Analysis Formula Collection+Frequently Asked Questions Summary! Collect it! Take a look before the exam and get an extra point!

Hello, little friends

The 2022 multi-provincial civil service examination was restarted on July 9.

The sprint time for preparing for the exam is less than one month.

What I shared today is

data analysisFrequently asked questions type identification, formula and quick calculation skills

Knowledge points are memorized by heart,The examination room is like a duck to water

Hurry up and learn with Tu Tu.

I. Amount of base period

I. Calculation of base period:

1. Find the amount of base period

[Identification] Given this year, find the quantity of last year. (Current quantity and growth rate are known)

[formula]

[Quick calculation skills] If 丨 r 丨 ≤5%, divide it into multiplication; If è r 丨 > 5%, truncate and divide directly.

2. Base period difference:

[Identification] Give the numerical value of a certain word this year and the growth rate of this year compared with last year, and ask how much is the difference between these two words last year? That is, to find the difference between the occurrence period and the growth rate.

[formula]

[Quick calculation skills] 1. If the option is two positive and two negative, two sets of the same data: exclude the current difference and compare the sizes; 2. If the option is four values: calculate two base periods separately; if direct division is adopted, three digits are truncated and two digits are calculated.

Second, the base period quantity comparison:

[Quick calculation skills] First look (fractional nature, magnitude), second calculation (truncation and direct division)

Second, the growth amount

I. Calculation of growth:

1. [Identification] Give the values of this year and last year, and ask whether this year’s XX is more (less) than last year’s … yuan (tons, mu …)?

[Formula] Growth amount = current amount-base amount, and decrease amount = base amount-current amount

[Quick calculation skills] The mantissa method and truncation are the same

2. [Identification] Given this year’s numerical value and year-on-year growth rate, ask whether this year’s XX is … yuan (ton) higher/lower than last year’s.

[formula]

[Quick calculation skills] When the growth rate is greater than 0, the growth rate is ≈1/n, and the growth amount = current amount /(n+1) (referred to as the principle of n+1).

When the growth rate is less than 0 and the reduction rate is ≈1/n, the reduction amount = current amount /(n-1) (referred to as the n-1 principle for short).

3. Average annual growth

[Identification] How much does XX-XX increase annually on average (tons, mu …)?

[Formula] Average annual growth =

[Quick calculation skills] Cut off the position and divide it directly

Second, the growth comparison:

1. The current amount and base amount are given.After calculation and comparison, some problems can also be judged by directly observing the column height difference.

2. Given the current volume and growth rate：

[Formula] Big is big (if the current volume is large and the growth rate is large, the growth amount must be large); One big one underestimates the product (the larger the "current quantity ×r", the greater the growth).

Note: If the difference between "1+r" is too large (several times), "current quantity ×r" cannot be used for comparison.

Comparison of change amount: if the current amount is large, the change amount is large; The larger the product of current quantity ×r, the larger the change.

Fractional percentage conversion table

Third, the growth rate

I. General growth rate：

1. Calculation of growth rate

[Identification] A is more than B (increased/expanded/increased) …% (times)

(1) percentage points, rate of addition and subtraction.

② [Formula]

"Quick calculation" Truncated direct division

2. Calculation of reduction rate

[Identification] A is less (decreased) than B..

[formula]

"Quick calculation" Truncated direct division

3. Comparison of growth rates

[Quick calculation skills] Incremental substitution method, multiple substitution method and score comparison method (one look and two calculations)

Second, the special growth rate:

1. Interval growth rate

[Identification] Time interval is one year, and the growth rate is calculated.

[Formula] R = R1+R2+R1× R2

[Quick calculation skills] 1. Both R1 and r2 are less than 10%, ignoring r1×r2；; 2. When calculating r1×r2, use the special fraction method.

2. Mixed growth rate

[Identification] The whole appears to be composed of parts, and the growth rate is sought.

[Formula] The overall growth rate is between some growth rates, and it is biased towards the side with a large base (biased towards the side with a large base period, generally replaced by the current amount).

Common can use some statements of mixed growth rate rule:

Annual = first half+second half = first three quarters+fourth quarter; Import and export = import+export;Real estate = real estate+real estate;Total transportation = freight+passenger;Export value = import value+surplus;Urban and rural = town+country

Fourth, the specific gravity

definitionSpecific gravity refers to the proportion of a certain part or individual in the total, which is generally in the form of percentage.

Question type characteristics: the proportion of a; The proportion of a in b.

formula: Specific gravity = partial quantity/total quantity

Classification of questions:

First, the calculation class

Question 1: What is the proportion of A to B in the current period?

Specific gravity = partial quantity/whole quantity, and the truncation is divided directly.

Total quantity = partial quantity/specific quantity, truncated direct division.

Partial quantity = whole quantity × specific gravity, and special value or scaling is considered in multiplication.

Question 2: what is the proportion of a to b in the past year?

Formula: specific gravity of base period =

Quick calculation skills: calculate half; Split-1 method

Question 3: According to the difference between the two periods, the proportion of A to B this year has changed by … percentage points (%) compared with the previous year?

Formula: Difference of specific gravity between two periods =

Second, the specific gravity comparison:

Score comparison method (one look, two calculations)

V. Average value

average numberIt is a quantity that represents the trend in a set of data, and it refers to the quotient obtained by dividing the sum of all data in a set of data by the number of this set of data.

characteristic: "every", "average" and "company" appear.

formula: Average = Total/Total = Back/Front

Error-prone unit conversion: 1 ton =2000 Jin, 1 hectare =15 mu.

Question 1: Average multiple numbers.

Formula: average = total number/total number

Quick calculation skills: ① observation; ② Median value method.

Question 2: What are the numbers of "every ……", "all ……" and "unit ……" this year?

Formula: current average = total number/total number = back/front =A/B

Quick calculation skill: direct division by truncation

Question 3: What was the number of "every …", "all …" and "unit …" in the past year?

Formula: base period average =

Quick calculation skills: calculate half and split one method

Question 4: The average of XX this year is RMB/person higher (lower) than last year?

Formula: average growth =

Question 5: The average of XX this year is ……% higher (lower) than last year?

Formula: average growth rate =

Six, multiple

Multiply is the relative number compared by two related indicators.A is A/B times that of B.

Question 1: Is A … times that of B this year?

Formula: current multiple =A/B

Quick calculation skill: direct division by truncation

Question 2: Last year, A was … times that of B?

Formula: base period multiple =

Quick calculation skills: calculate half and split one method

VII. Comprehensive analysis

[Skill]

1. Error-prone points (ask √ skip, ask × look first): percentage, deficiency, doubling, and favorable deficit.

2. Simple priority:

(1) first look at the options of formula (two-period proportion, two-period average, growth comparison, mixed growth rate, etc.), direct reading and simple addition and subtraction.

(2) give priority to the material "year" option, and the time point gives priority to the time period.

③ Skip the interval year, the ratio of base period, and those that are complicated in calculation and incomprehensible.

pithy mnemonic formula: ① comparison of two periods (A > B, rising; A < b, down); ② Comparison of base period (lean camel is bigger than horse: the base period with obvious current period is generally bigger); (3) comparison of growth (the bigger the product, the bigger the product); (4) Mixed class (the whole is between the parts, and it is biased towards the party with larger cardinality)

Collect it! Take a look before the exam and get an extra point!