Statistically Confident
Principal Aspect by Mr. Roderick R. Mendiola, Principal II – CMSHS
Editor: Ms. Roxane S. Villanueva

A FEW days before the May 9, 2016 election, then presidential bet Rodrigo Roa Duterte knew that a fair election would catapult him to the presidency. His hope of topping in the race was strengthened not by his political machinery, but by pre-election surveys that consistently suggested his popularity gaining ground among registered voters across the country. The strong opinion polls heralding his imminent victory eventually sealed his stardom and magnified his confidence in the practical utility of data.
The poll conducted by Social Weather Stations (SWS) on May 1–3, 2016 registered around 33% of voting Filipinos rooting for Duterte – a good deal of proportion emphasizing his juggernaut of a “market share” in the seat of presidency relative to that of Poe’s (22%), Roxas’s (20%), Binay’s (13%), or Santiago’s (2%). (Ten percent of those sampled either were undecided or had their responses invalid for lack of information elicited.) Stars were aligning for Duterte as the big day neared: consistent poll results based on 4,500 respondents rendered his lead in the national survey translatable in reality. True enough when the canvassing was over, 39% of those who exercised their suffrage voted for Duterte in the long run – a 6-point increment that may have accrued from part of the 10% reflected in the said SWS report.
Such appreciation of data has been everywhere present early on in our schooling lives; and even in adulthood, it never goes out of style.
The ability to formulate sound generalizations from a survey or any research data leads to effective decision-making when developed properly. Thankfully, the K to 12 Basic Education Curriculum has not fallen short of including a core subject in senior high school (SHS) that is relevant to honing learners’ numerical and statistical fluency, thereby increasing their decision-making power: Statistics and Probability.
In this 80-hour course, SHS learners are expected to undergo sessions on estimating parameters (i.e., values describing the characteristics of a population), and likewise engage in hypothesis testing. The topics covered are geared towards equipping our students with statistical skills for future research endeavors or other possibilities requiring their use.
For instance, given the percentage distribution of the most preferred snacks of 100 students at a certain high school as follows: Turon–50%, Suman–27%, Biko–23%, students in entrepreneur class wouldn’t run into the difficulty of choosing which snack to sell because, aside from the fact that turon stood out from among other offerings, the food item would attract 40%–60% (50% ± 10%) of the “snacking” student population, 95% of the time! Simply put, if these students were to market the product to their schoolmates 100 times over, 95 of these repeated occasions would guarantee between 40% and 60% of this population buying turon. (The confidence interval 40%–60% is derived from the formula and computation:

where represents the proportion in decimal of students preferring turon as their most favorite snack and
the sample size. The standard deviations ± 1.96 provide for a 95% level of confidence that such interval will contain the true population proportion of students opting turon for a snack.)
With deep knowledge of and skills in statistics and probability, students are led towards becoming data-driven individuals, who treat survey results, for example, with utmost caution to arrive at a sound assumption – not easily swayed by anything heard or read in the online world, but statistically confident in rectifying information doctored by trolls.